My block is cracked on my 1991 chevy 3/4 ton 4x4 pickup. I took the heads off and there is a 2" crack in one of the cylinder walls.

In the last 500 miles I have put on a new IP, new injectors, new glow plugs (60g), new batteries, and finally a new 700r4 transmission and throttle position sensor.

As you can see I have spent allot of money on this truck so far. I have to draw the line somewhere and here it is.

I will not be fixing this truck anymore.

Thanks

:nopics::damnit1:

That sucks to loose an engine. I do have a 1985 6.2 available if you make a reasonable offer. I'll be honest, if you let it sit for 4-5 days it takes 30 sec of cranking to start. (It's about 38 deg here in Utah right now and it was not plugged in.) Once started, run for a minute, and then restarted 4 hours later (cold) it starts up well. I think the fuel is bleeding back to the tank. Oh, and the injector pump chirps, but from the post is looks like you have a new one.

The engine is complete from flexplate to radiator, air cleaner to oil pan. I think it has 236K on it. The only part taken is the alternator. Why am I selling it? I buy and sell automotive stuff to get my way through college. This one happens to be in a suburban that was impounded .

This is the only pic I have now the truck is in Hastings and I am near Omaha.

I found a used block for $200 and there are Mahle rebuild kits on ebay for $635. Are these quality parts? I have $3500 in the truck already is it worth it to rebuild the engine for $1000 - $1500.

What causes blocks to crack? How would I know if this used block is going to crack or not?

My Engine oil cooler was disabled before I bought it. The lines leaked and the holes were plugged. Would this cause a block to crack?

Thanks for your help.

Haven't heard of the cylinder walls cracking other than yours. Much more common to crack the mains. I'd throw on a stud girdle when you rebuild it just to be on the safe side. I think they're around $170-180 canadian through DSG. It'd also be worthwhile to fix the oil-cooler lines. If a rad has oil cooling there is good reason to use it.

Blocks usually crack due to major overheating. Rather unusual to have a crack in the cylinder wall, though... Usually they crack around the main bearings. Are you sure that it isn't just scored really bad, maybe from a foreign object in the combustion chamber? I suppose that the oil cooler could have had an effect on it, but sounds more like it was overworked and overheated really badly (although it may have happened a long time ago).

As far as I know the rebuild kits are good. The block may be good... Just make sure that there are no cracks aroung the main bearings. Make sure your heads are in good shape before you do anything, though... Head work can get really expensive really fast.

If you are careful putting it together, run an oil cooler, and make sure you have a good radiator, there is no reason for the new engine to fail.

Just remember... You know what you've got right now. If you sell it (which is going to be hard with the engine taken apart) and buy something else, you don't know what you've got anymore... You may end up with the same problems.

By the way, rock shoes is right. A stud girdle kit is a very good idea.

Haven't heard of the cylinder walls cracking other than yours. Much more common to crack the mains. I'd throw on a stud girdle when you rebuild it just to be on the safe side. I think they're around $170-180 canadian through DSG. It'd also be worthwhile to fix the oil-cooler lines. If a rad has oil cooling there is good reason to use it.

What is a stud girdle and who is DSG?

The cylinder is rusty and the head gasket is not blown. It is rusty because the truck sat for a coupple of months before I worked on it. I am 90% sure it is a crack. I canot see anyother way water could have gotten in the oil.

What is a stud girdle and who is DSG?

The cylinder is rusty and the head gasket is not blown. It is rusty because the truck sat for a coupple of months before I worked on it. I am 90% sure it is a crack. I canot see anyother way water could have gotten in the oil.

A stud girdle is a bar that bolts on down the mains and stiffens the entire bottom end of the block. It makes a huge difference in preventing the cracked mains that are a known issue with 6.2/6.5 blocks. DSG stands for Diesel Services Group. Should get the website if you try googling it. They make some specialty products for 6.2/6.5 engines.

Look for a cracked head (cylinder head, that is ):h)... That is much more likely to be the problem.

I have never heard of one getting a crack in the cylinder wall... I am sure it has happened, but I am also sure it almost never happens.

Would the crack in the head be noticable to the naked eye? I cannot see any crack in the head.

Another ? I can get a rebuilt 6.5 from a repair shop in town. The guy claims he bought it for a guy to put in his van and the guy left and stuck him with the engine and some labor. He wants $2000 for the engine. I think I might be able to talk him down. The question is can I put in a 6.5 in this truck and still use the new IP, injectors, glow plugs and all the other parts I have?

The first gen 6.5's used the same IP. Not sure about the injectors. Pretty sure you can use the glow plugs. are you getting the turbo with it?

Not sure yet I will know more tommorow. Is a 6.5 internally a 6.5 no matter what year.

Would the crack in the head be noticable to the naked eye? I cannot see any crack in the head.
Another ? I can get a rebuilt 6.5 from a repair shop in town. The guy claims he bought it for a guy to put in his van and the guy left and stuck him with the engine and some labor. He wants $2000 for the engine. I think I might be able to talk him down. The question is can I put in a 6.5 in this truck and still use the new IP, injectors, glow plugs and all the other parts I have?

You can put in a newer 6.5 - but what year? The 6.5s built in 93 have heavy blocks. After that they were cheapened and more prone to cracking than the 6.2s and the first year 6.5. Also, if it was a turbo engine, it will have different pistons than a non-turbo - and a lower compression ratio. There are newer-than-94 6.5s around that are non-turbo and mechanically injected - they were sold as replacement engines - not OEM. Also, the 6.5s are not as fuel efficient as the 6.2s - as they have subtle changes from the 6.2 - e.g. different precombustion chambers, different injector angles, most have a lower compression ratio, etc.

And what, exacty, does "rebuilt" mean. The definition seems to vary a lot with people selling engines. When it comes to 6.2 or 6.5 diesels - I would not touch a rebuilt - since the metal has already seen a lot of stress. Take a block and crank - clean it, bore the cylinders, polish or grind the crank - and what do you have? A block with some built-in metal fitigue, and a crank also with fatigue and perhaps less metal in it. New bearings an pistons don't eliminate metal fatigue.

I'd take a good, under 120K used engine over a rebuilt anytime.

Everybody views spending money in different ways. If it were me? There are good 6.2s available in the $200 - $300 price range - often with less than 100K miles. I'd buy one of them, pull the oil pan, put in the stud-girdle kit, and swap the injection pump and injectors if needbe. That's a lot cheaper than spending $2000 on a 6.5 and not being sure of what you are getting.

In regard to cylinder wall cracking - I've got two 6.2 blocks in my shop with cracked cylinder walls. I have no history for them though - so I can't say what caused it. They are part's engines I bought for $50 each and stripped. I've also got three others with cracked main-bearing webs.
In past experience though, cracked cylinder walls are either caused from a low-coolant level and hot-spots on the cylinder wall - or - the oldfashioned no-antifreeze and a coolant freeze-up.

You can put in a newer 6.5 - but what year? The 6.5s built in 93 have heavy blocks. After that they were cheapened and more prone to cracking than the 6.2s and the first year 6.5. Also, if it was a turbo engine, it will have different pistons than a non-turbo - and a lower compression ratio. There are newer-than-94 6.5s around that are non-turbo and mechanically injected - they were sold as replacement engines - not OEM. Also, the 6.5s are not as fuel efficient as the 6.2s - as they have subtle changes from the 6.2 - e.g. different precombustion chambers, different injector angles, most have a lower compression ratio, etc.

And what, exacty, does "rebuilt" mean. The definition seems to vary a lot with people selling engines. When it comes to 6.2 or 6.5 diesels - I would not touch a rebuilt - since the metal has already seen a lot of stress. Take a block and crank - clean it, bore the cylinders, polish or grind the crank - and what do you have? A block with some built-in metal fitigue, and a crank also with fatigue and perhaps less metal in it. New bearings an pistons don't eliminate metal fatigue.

I'd take a good, under 120K used engine over a rebuilt anytime.

Everybody views spending money in different ways. If it were me? There are good 6.2s available in the $200 - $300 price range - often with less than 100K miles. I'd buy one of them, pull the oil pan, put in the stud-girdle kit, and swap the injection pump and injectors if needbe. That's a lot cheaper than spending $2000 on a 6.5 and not being sure of what you are getting.

In regard to cylinder wall cracking - I've got two 6.2 blocks in my shop with cracked cylinder walls. I have no history for them though - so I can't say what caused it. They are part's engines I bought for $50 each and stripped. I've also got three others with cracked main-bearing webs.
In past experience though, cracked cylinder walls are either caused from a low-coolant level and hot-spots on the cylinder wall - or - the oldfashioned no-antifreeze and a coolant freeze-up.

This sound like good advice to me. Where would I go about finding a used engine? A gaser is one thing a used diesel might be harder to find.

That sucks to loose an engine. I do have a 1985 6.2 available if you make a reasonable offer. I'll be honest, if you let it sit for 4-5 days it takes 30 sec of cranking to start. (It's about 38 deg here in Utah right now and it was not plugged in.) Once started, run for a minute, and then restarted 4 hours later (cold) it starts up well. I think the fuel is bleeding back to the tank. Oh, and the injector pump chirps, but from the post is looks like you have a new one.

The engine is complete from flexplate to radiator, air cleaner to oil pan. I think it has 236K on it. The only part taken is the alternator. Why am I selling it? I buy and sell automotive stuff to get my way through college. This one happens to be in a suburban that was impounded .

How many miles are on this engine. The problem doesent sound like an engine problem more like a fuel delivery problem. Does anyone agree?

Yeah that sounds like it has some fuel delivery issues. Not much else from what I've read. You'll have to check it out closely. Personally I think I'd look for one with around 130-160K on it instead.

A machine shop in Hastings is having a Liquidation Auction. They have complete and core 6.2 Engines. I have to look into it further to see if the complete engines are rebuilt but it may just work out in my favor. There cannot be many people in and around Hastings Nebraska looking for 6.2 engines. I might be able to pick one up cheap.

This sound like good advice to me. Where would I go about finding a used engine? A gaser is one thing a used diesel might be harder to find.
How many miles are on this engine. The problem doesent sound like an engine problem more like a fuel delivery problem. Does anyone agree?

I find engines all over. I rarely pay more than $200 for a good engine. Problem is - determing the actual mileage since most were in vehicles with 6 digit odometers. That means you have to rely on the honesty of the seller. I often get replies like "it must have low miles because it runs so good." Well - that is a useless answer. MY 87 Suburban had over 500,000 miles and ran like new. I just bought a 91 6.2 with 90K verified miles out of a G30 school bus. Also just passed on one on Ebay - a 92 6.2 diesel with 70K miles. The guy wants around $1200. It's still for sale as far as I know. I live in a area where diesel vehicles often rust out before they wear out. And, early 80s trucks with 6.2s often got blown 700R4 transmission and then got parked and never used again. I bought three K5 diesel Blazers from the Long Island NY area - all with less then 70K miles on them in the price ranges of $1800 for the best one with a plow and new replacement T400 trans, to $600 for an 86 K5 with 60K miles and a blown trans. I just bought - last week - a 88 6.2 with 110K miles with a complete Banks turbo setup - paid $700 for the entire package - but it also cost me $250 to ship it.
I also bought a fire-department 88 GMC 4WD 6.2 Suburban for $700 - runs great and has 75K miles on it - but the interior is completely stripped - it only has a front seat and the rest is bare.
Last month - some guy had an 86 Suburban for sale on Ebay - and it was only 30 miles from where I live. He said it had a new "crate" 6.2 engine and a new 700R4 trans and new tires and plow - but the body was rusted out. Asking price was $1200. I contacted him and right away he backed off his "crate' engine story - and commenced to tell me how good it ran - so it "must be a crate." I then asked if I could come by and look at it - and he got kind of defensive about the whole deal. He basically said that I was a nit-picker jerk asking too many questions. Some other guy got the deal -and then backed off and they both have a running dispute on the Ebay feedback column. So, it's still for sale as far as I know. The guy changed his description on Ebay and no longer mentions the "crate" engine. You can still see it on Ebay - look for item # 320039420084.
In regard to the other posters suggesting you don't need an engine? Hey, I've been working on diesels for 40 years - and I still can't diagnose them "over the phone" or via the Internet.

Find out what is really wrong with your current engine. Of course, if you can get a good 6.2/6.5 for a $200-$300 that is good since it will probably cost you that much to put your existing engine back together with new head gaskets, much less heads, etc... But lately they have been selling for a lot more than that.

Take a bit of fine sandpaper (I like 600 grit) and some WD-40 and gently clean the rust from the cylinder wall around the "crack"... Then spray it down with brake cleaner. Now you can get a look at it. See if it is really a crack. I doubt that it is... Look anyway. If it is cracked... Yep, you need to find another engine. If it isn't...

Look at the heads very carefully...The crack will probably be visible, but you need to look closely. You may need to clean the head to spot it.

No crack in the head or the block? Check out the head gaskets. I know you said they looked fine, but if there is nothing else wrong with it... Post pictures of them if they become suspect.

Another thing to note... If the head gaskets are in fine shape but the heads weren't torqued down properly... There's the problem.

Don't buy the $2000 engine. You don't know what you are getting and it isn't absolutely certain that you need it yet. Find out whether you really need an engine or not before you go and buy one.

Hope this helps! :)

Check this eBay listing out 190051154143

This is only 30 miles from me.

What do you think?

Any concerns?

Find out what is really wrong with your current engine. Of course, if you can get a good 6.2/6.5 for a $200-$300 that is good since it will probably cost you that much to put your existing engine back together with new head gaskets, much less heads, etc... But lately they have been selling for a lot more than that.

Take a bit of fine sandpaper (I like 600 grit) and some WD-40 and gently clean the rust from the cylinder wall around the "crack"... Then spray it down with brake cleaner. Now you can get a look at it. See if it is really a crack. I doubt that it is... Look anyway. If it is cracked... Yep, you need to find another engine. If it isn't...

Look at the heads very carefully...The crack will probably be visible, but you need to look closely. You may need to clean the head to spot it.

No crack in the head or the block? Check out the head gaskets. I know you said they looked fine, but if there is nothing else wrong with it... Post pictures of them if they become suspect.

Another thing to note... If the head gaskets are in fine shape but the heads weren't torqued down properly... There's the problem.

Don't buy the $2000 engine. You don't know what you are getting and it isn't absolutely certain that you need it yet. Find out whether you really need an engine or not before you go and buy one.

Hope this helps! :)

I had a really good friend of mine an experienced mechanic check it out. It is defiantly cracked, %100 sure. I do not know how. I did some work on the thermostat recently maybe there was an air bubble. Don't know don't matter anymore.

Check out the previous post.

Will I have to swap the oil pan because mine is a 4x4 and this came out of a 2wd?

Find out what is really wrong with your current engine. Of course, if you can get a good 6.2/6.5 for a $200-$300 that is good since it will probably cost you that much to put your existing engine back together with new head gaskets, much less heads, etc... But lately they have been selling for a lot more than that.

Take a bit of fine sandpaper (I like 600 grit) and some WD-40 and gently clean the rust from the cylinder wall around the "crack"... Then spray it down with brake cleaner. Now you can get a look at it. See if it is really a crack. I doubt that it is... Look anyway. If it is cracked... Yep, you need to find another engine. If it isn't...

Look at the heads very carefully...The crack will probably be visible, but you need to look closely. You may need to clean the head to spot it.

No crack in the head or the block? Check out the head gaskets. I know you said they looked fine, but if there is nothing else wrong with it... Post pictures of them if they become suspect.

Another thing to note... If the head gaskets are in fine shape but the heads weren't torqued down properly... There's the problem.

Don't buy the $2000 engine. You don't know what you are getting and it isn't absolutely certain that you need it yet. Find out whether you really need an engine or not before you go and buy one.

Hope this helps! :)

Find out what is really wrong with your current engine. Of course, if you can get a good 6.2/6.5 for a $200-$300 that is good since it will probably cost you that much to put your existing engine back together with new head gaskets, much less heads, etc... But lately they have been selling for a lot more than that.
No crack in the head or the block? Check out the head gaskets. I know you said they looked fine, but if there is nothing else wrong with it... Post pictures of them if they become suspect.
Hope this helps! :)

My experiece has been different - as to the prices on 6.2s. I've been passing up many more that I've been buying - and they seem to be all over the place lately. The military is selling them in container loads with starting bids of $25 per engine - but you have to buy 20 engines at a time. And condition - ?? Also, the low-miles, tested Humvee takeouts are numerous - but usually in the $1000 price range.

Just in the past month - I've had the chance to buy over a dozen good running 6.2s in the $200 price range - but I won't buy one if the miles are unknown. I'm not going to waste my time with an engine that might have over 300K miles on it - good running or not. Besides the privately owned engines - there have been many G30 shoolbus/van 6.2 engines for sale recently. At least with them - you can usually verify miles and maintenance.

Back to this guy's problems. If the cylinder wall is actually cracked (and I have seen a few 6.2s that were), it would show on the piston skirt. Coolant entering through the cylinder wall and upsetting the piston-skirt lubrication will invariably show metal transfer and wear. If the piston looks fine in that area - it is NOT leaking coolant there. In regard to the heads and crack-leaks - any decent machine shop can magnet-check for cracks in minutes and tell for sure.

I agree with the cost of parts versus engine replacement. Parts cost are so high - that is often is not worth rebuilding an engine when compared to buying a good running 6.2. It's kind of shame, but that's the way it is. Even components are getting non-cost effective to repair. For example - I pulled the injection pump of an 87 for "routine maintainance" - since it was running perfect but had over 200K miles. Once apart - I found some chipping and wear in critical areas - i.e. the cam ring, head & rotor, etc. The cost to me just for the replacement parts was over $400 - while I could buy a tested, rebuilt, and guaranteed pump for $300. So, although it went against my nature - I bought a pump that somebody else had worked on. Water-pumps? - I used to rebuild my own - part's cost now for a bearing assembly and seal is close to $40. I can buy brand new water pumps (not rebuilt) for $45 - so why bother fixing? Starter motors - olds style direct-drive Delco - new HD starter drive, brushes and holders, bushings, solenoid repair kit, etc. often over $50 in parts for what is an inadequate starter anyway. I buy brand new, high-torque, gear-reduction Chinese starters for $87. They work great - so the old starter is not worth messing with. Mater brake cylinders? - a kit often cost over $20 and won't fix a scored cylinder anyway. Brand new cylinder from China - $45. Fuel injectors - rebuild them myself with new tips for $16 each, or buy them rebuilt for $22 - $30 each - yet - I often find brand new Stanadyne injectors - complete - no core trade in - for $23 each. So, again - not worth messing with.
Take a 6.2. Pay perhaps for some machine work, cleaning, magnafluxing, etc. Buy new gaskets, timing chain set, pistons and rings, main and rod bearings, and you are very soon well over $1000 . I do my own machine bench work - milling, cylinder head rebuilding, etc. - just about all but cylinder boring - and it's still not usually worth it - unless I want a custom built engine and don't mind paying the extra bucks.
A factory "virgin" 6.2, with OEM parts - is an excellent engine and a "best buy" if you can find one in good shape.

I had a really good friend of mine an experienced mechanic check it out. It is defiantly cracked, %100 sure. I do not know how. I did some work on the thermostat recently maybe there was an air bubble. Don't know don't matter anymore.

Check out the previous post.

Will I have to swap the oil pan because mine is a 4x4 and this came out of a 2wd?

All right, well since it is definitely cracked you are definitely going to want a replacement engine, probably a used engine. Glad we know for sure now... Wouldn't want you to have to replace anything you don't need to replace... :)

I looked at the one you mentioned in your previous post... Looks good to me, but it is sold now... You buy it? If you did, do not assume the transmission is good, but the engine should be fine... I don't think you would have to change the pan.

If you didn't get that one, don't forget your local junkyard... Many times they are the cheapest option. I would recommend buying one you can hear run before purchase, though.

I will not be installing the trans. You probably do not remember but about 4-6 months ago I had my trans break down and I replaced it with a rebuilt one. I will use that one.

I also have a new IP but it is for a 91 I have been told that the new IP's are set to deliver more fuel and it may smoke a bit. Do you think I should put in my new IP or use the used one that the seller installed?

Are there any gains or loss in power with the extra fuel delivered by the new IP and will the mileage suffer any? I previously got 20.

Is there anything I can check while this used engine is out of the truck?

Can I pull the pan and check anything or should I just leave it alone?

Should I put a stud girdle on this engine while it is out of the truck?

I will not be installing the trans. You probably do not remember but about 4-6 months ago I had my trans break down and I replaced it with a rebuilt one. I will use that one.

I also have a new IP but it is for a 91 I have been told that the new IP's are set to deliver more fuel and it may smoke a bit. Do you think I should put in my new IP or use the used one that the seller installed?

Are there any gains or loss in power with the extra fuel delivered by the new IP and will the mileage suffer any? I previously got 20.

Hi , do not expect any loss of mpg ,in case of black smoke look at the sticky on the top of the 6.2 section .
What number that IP from 91? there is many models and setup possible.

Should I put a stud girdle on this engine while it is out of the truck?

Yes that's a mojor upgrade for your engine safty and your peace of mind:)

Ed

You can put a stud girdle on it... Makes it a lot stronger.

I would just put it in... If you are a little nervous about it, pull the heads and install new gaskets before you put it in. A lot easier when it is out of the truck, as I am sure you know.

The IP should be fine if it is in good working order... More fuel can never hurt. It won't smoke anywhere other than at high throttle conditions.

Does the block crack at the main bearings under normal wear or does a person have to abuse it.

I do not drive this truck much it is not my primary vehicle. This trucks primary purpose is to get fire wood and building materials. My driving is 80% highway. About 65mph.

Do you still think stud girdles are a must? The thing is the girdles cost more than 1/2 of what I am spending on the engine. How often do they really break? I am not tough on my vehicles I drive like grandma and do not pull much over long distances.

Thanks

6.2 blocks are like concrete, There is two kinds of blocks, those that are cracked & those that are going to be cracked. Stud girdle is nice but not required.

Does the block crack at the main bearings under normal wear or does a person have to abuse it.

I do not drive this truck much it is not my primary vehicle. This trucks primary purpose is to get fire wood and building materials. My driving is 80% highway. About 65mph.

Do you still think stud girdles are a must? The thing is the girdles cost more than 1/2 of what I am spending on the engine. How often do they really break? I am not tough on my vehicles I drive like grandma and do not pull much over long distances.

Thanks

I've seen so many of them cracked at the mains I wouldn't even dream of taking one of them apart without putting one in. For what they cost it really is worth the peace of mind.

Then again, as Kin Pin pointed out, most of them crack... Most of them also run fine with those cracks.

Chances are that the engine you bought already has cracks. You should put the stud girdle in, but if you don't it will probably be fine. Don't abuse it and make sure the harmonic balancer is good and chances are that everything will be just fine...

Then again, as Kin Pin pointed out, most of them crack... Most of them also run fine with those cracks.

Chances are that the engine you bought already has cracks. You should put the stud girdle in, but if you don't it will probably be fine. Don't abuse it and make sure the harmonic balancer is good and chances are that everything will be just fine...

So if they are cracked the stud girdle keeps it from breaking and if they are not cracked the stud girdle keeps it from even cracking. Am I thinkging correctly?

Has anyone seen one break even with the stud girdle?

Make sure your IP is in good shape & don't run the IP Timing too fast as this will create more stress on the crank & the block also.

I plan on using my new rebuilt IP off of the 91 engine. I also plan on setting the timing at the marks and taking it to the diesel shop to have it timed.

Sound good?

Sounds good!!!!!!!!!!

So if they are cracked the stud girdle keeps it from breaking and if they are not cracked the stud girdle keeps it from even cracking. Am I thinkging correctly?

:exactly:

By the way, they can break with a stud girdle installed, but generally that is on highly modified engines (turboed with lots of boost and possibly nitrous oxide). With a stud girdle on a stock engine you'll be plenty safe.

Sounds like you are going to be all set now... :cool2:

I bought a stud girdle set from a member in the classified section.

The seller of the engine called me. He said it was his bosses truck and he has known it from its birth. It is a 1 owner engine and was only used to run errands. The 90K is original miles. He also said a local trany shop said the 700r4 has a core value of $150. That makes the engine cheaper. The injectors are in fact newly rebuilt and have never been run. It also comes with the old broken IP.

Also the engine does not leak this is a plus.:cool2:

Sounds like you found a great transplant candidate. Good luck with it.

I bought a stud girdle set from a member in the classified section.
The seller of the engine called me. He said it was his bosses truck and he has known it from its birth. It is a 1 owner engine and was only used to run errands. The 90K is original miles. He also said a local trany shop said the 700r4 has a core value of $150. That makes the engine cheaper. The injectors are in fact newly rebuilt and have never been run. It also comes with the old broken IP.lso the engine does not leak this is a plus.

I didn't read through all the posts - but sounds like you bought the Ebay engine? If so, I'm glad I didn't bid on now - and I almost did. There's been almost an engine a day - 6.2s that is, selling around $200 - $300. The one you got - somes like the mileage story is believeable. Two weeks ago, also in Nebraska - someone had a pair of K5 6.2s, both with under 80K miles - and they went for $150 - each. If I had bought them, however, shipping would of cost me another $500-$600.

About the stud-girdles - I know of one that a guy put on after seeing his block was cracked and he's put 80K on it since. But - I also know a guy with a cracked block and he's just driving it 'till it blows - no girdle - and it's been a year or so. Seems there is no real scientific evidence out there - but the girdle HAS to help. As to high-performance 6.2s and 6.5s - the ones I've seen don't use the girdles. They redrill the end bolts on the main bearings, cant them at a new angle, grab a different part of the block, and stud them.

As far as claims that having your fuel timing advanced will shorten the life of the engine? Personally, I don't believe it for a moment - someone show me some evidence. My 87 - with years of fairly heavy towing, no overdrive and spinning at 2700 RPM most of the time, and the fuel delivery turned up and the the total advance upped by 3 degrees - made it to 517,000 miles.

Explain turned up 3 degrees? Past what spec & with what kind of meter.

OK I have read some things about early 6.2 heads having problems cracking between the valves and something about a cooling port that was not the best design. It leaks by the head gasket or something.

What can I do to keep this running without problems? I am not asking for modifications just what kind of maintenance thing to I need to be aware of in order to keep it running?

Explain turned up 3 degrees? Past what spec & with what kind of meter.

Three engine degrees of advance over stock OEM advised setting - which equals 1.5 degrees at the pump since it runs half-speed. Measured with a light-sensor via a glow-plug hole. I don't do it the same way with all my 6.2s ( I have over a dozen). Every engine is an individual. Maybe if they were German or Japanese built with much closer machining tolerances - that would not be the case - but it is. So, they differ when new, and even more so when used. And, a stretched timing chain makes conventional OEM general settings kind of useless.
Advancing static (initial) timing is one thing - but the total advance can be altered independently which I've done on one of mine - since on that vehicle - I wanted more advance had high RPMs than I wanted at engine idle.
On industrial and forestry equipment, especially with DB pumps, independent adjustment is much easier to do via a trimmer screw.
I also have a pulse-adapter that converts injection-pulse to a signal a conventional timing light can use. Problem with that is "pulse lag" - so this sort of timing reading will not be exactly the same as a glow-sensor and must be adjusted for. Also, if an engine has old injectors that have "settled" a bit with a lower then new opening pressure, then the lag changes and the actual timing changes a bit - but not enough to be noticed.
If you want to discuss timing and specs. - you have to clarify who's specs - GMs., Standynes, and measured by what device.
The reality is - you can set most by "ear" and be fine - as long as you have an experienced ear. In fact, it often works better that way.
I've been working on diesels for 40 years - so that could make me smart - or perhaps just stubborn. I probably have a mix of both - but I tend to be skepical of things unless backed by proof. And -with the Standayne/Roosamaster injection pumps -made by former Hartford Machine Screw Co. - they sold their first rotary pumps in 1952 for use on Hercules engines in Cletracs. The newer DB2 pumps are not all that different.
Now - maybe I answered your question - and maybe not. But my question to you is - about your analogy of 6.2 blocks to concrete. What does that mean? Not all concrete cracks - and I suspect not all 6.2 blocks crack. I've yet to see an 82 block cracked at the main-bearing webs, and I haven't seen any newer 10149599 blocks crack there either - but I haven't seen them all. And - the statement about a stud-girdle not being necessary? Well no . . ., neither is driving or owning a truck necessary. But - will it enhance the life of a 6.2 block? I will assume it must. If you feel otherwise - that is fine if offered as your opinion. But . . . if offered as fact - show some evidence or verified test-specs.

OK I have read some things about early 6.2 heads having problems cracking between the valves and something about a cooling port that was not the best design. It leaks by the head gasket or something.

What can I do to keep this running without problems? I am not asking for modifications just what kind of maintenance thing to I need to be aware of in order to keep it running?


Just keep the oil and coolant changed, don't overheat it, and it should be fine for a good long time.

Most cracks between the valves are not a big deal. They usually don't affect anything.

If you really want to make sure it is going to be problem free, you should replace the head gaskets and head bolts while it is out... That way you don't have to worry about it. If you don't it will probably be fine, but you might want to change them anyway.

Sounds like you've got a very good engine lined up to go in... :cool2:

OK I have read some things about early 6.2 heads having problems cracking between the valves and something about a cooling port that was not the best design. It leaks by the head gasket or something.
What can I do to keep this running without problems? I am not asking for modifications just what kind of maintenance thing to I need to be aware of in order to keep it running?

In regard to maintenance - regardless of what year or engine-code you have - keeping the heads from overheating will prolong their life. That means to never install a restrictive exhaust sytem like NAPA might sell you, and being very careful on long pulls up steep hills in hot weather.
Also - probably the most important is maintenance of the fuel injection system. That means - if the injectors have over 100K miles - they should be checked. And if the pump has over 100K miles - pay attention for signs of wear - like late timing advance, incorrect fuel delivery, etc. Symptoms can include excessive smoke at start-up, engine misfiring at high RPMs, black exhaust smoke under load, etc.
Also keep in mind that standard rotary injection pumps as used on civilian 6.2 diesels can last longer if you use a lubrication additive to your fuel. Some military versions use special extra-hard internal parts to deal with low-lube fuel.
Also - going by what General Motors suggested in prolonging the life of the older 350 Olds-based diesels - do not turn up fuel delivery and do not turn up the advance if you want to get the most life out of the head-gaskets and heads.
With the early 1982 engines and the leaking ports - GM sold a little kit to fix it - with plugs for those ports. In regard to head-cracking - the C code light-duty heads are more prone to cracking since the valves are larger diameters. J code HD engines have smaller valves and thus - more metal between them.

Where do I look on the engine for the engine code?

Also in regard to the oil cooler lines not connected I tested my oil temp after a 50 mile run and it was 210deg F (before block cracked) does this sound OK? Like I said I do not pull long distances, do not accelerate hard and do not drive over 65mph. I still do not want to pay the extra money to fix the oil cooler. I have too much invested in this truck already. What are some of your opinions?

Not all concrete cracks

All concrete cracks the key is controling where it cracks thats why concrete has control joints.

Fireball has got it, All 6.2's crack sooner or later.

Fireball has got it, All 6.2's crack sooner or later.

For you to know that to be true, you would need knowledge of every 6.2 ever built - and I know, for sure ,you don't.

You might be able to make a qualified statement about it - if you had any long-range scientific test data on all the variations of the 6.2 - and I doubt you do. IF you do - I'd like to get my hands on a copy. I've been searching for such info since the early 80s. I have some - but it's not comprehensive. My father-in-law is a retired Detroit Auto engineer - and he's told me that he can't even get the data - if it exists.

And, even within your blanket statement - I assume, that . . . if they all crack -then that implies they must last long enough to do so. With that - I know it is wrong - since many never get enough miles on them for the cracking to even be a consideration.

And concrete? No - it does not always crack - as least not when using the everyday common meaning of "crack" as being deleterious to the integrity of the slab, pour, etc. Yes, concrete can get different degrees of cracking - due to many factors, e.g. cure rate, mix rate, environmental stress, etc. And, steel, cast steel, cast iron, etc. can develop cracks from heat, harmonics, etc. With the latter - usually such cracking can be detected in several ways - e.g. magnetic fluxing.

I will assume - that when you use the word "crack" as applied to a 6.2 casting, it must be a crack that can be detected by conventional machine-shop means. Otherwise - I don't consider it worth discussing. That being said - I recently had the heads off my 6.2 with 517,00 miles on them and there are NO detectable cracks. These are the HD J code heads with the small valves. I also have two 6.2 blocks - one with miles unknown but I know it was over 100K, and another with 237,000 verified miles on it. Both have been flux-tested and neither is cracked. I have another - a 1983 that was pulled as a "good runner" with only 70K miles and it is cracked in three places on the main-bearing webs. That engine was babied it's entire short life - it was my friend's father's truck.

I don't pretend to have the ability to predict which engines will, and which ones will not crack - or if so - when. I do know there have been, and will be 6.2 engines that make it over 400K without developing such cracks.
The mid-range engines The later 6.2s - castings 10149599 used smaller outside main-cap bolts to prevent block cracking along with a thicker casting. So, it seems by that point - someone knew about the cracking and tried to remedy it. I have spoken with several engine rebuilders and - as told to me - they rarely if ever find these newer blocks cracked.
With the older casting # 14022660 blocks - the 82s use the same casting number as later engines - but the 82 is supposed to have a higher nickel content. I can't prove it and GM wasn't gracious enough to mark the blocks. Why, I don't know? Back in the muscle-car days, GM made many gas engines with high-nickel and usually marked the blocks to designate. So, as far as I know - the only way to identify an 82 high-nickel block is by it's orange color, or heads that use coarse-thread injectors with 2.0 thread pitch and head casting # 14028901 (C code) and a T mark by the intake manifold. T = 1982, U = 1983, F = 1984, etc.

In regard to valve sizes - all the J code HD engines I've pulled apart have 1 1/2" exhaust valves and 1 3/4" intakes. All the LD C code engines I've pulled apart have 1 5/8" exhaust valves and 1 15/16" intake valves.

If anybody has any acurate and verfied info on 6.2s - please post with source-citations - I'd love to have it.

Where do I look on the engine for the engine code?

Also in regard to the oil cooler lines not connected I tested my oil temp after a 50 mile run and it was 210deg F (before block cracked) does this sound OK? Like I said I do not pull long distances, do not accelerate hard and do not drive over 65mph. I still do not want to pay the extra money to fix the oil cooler. I have too much invested in this truck already. What are some of your opinions?

The block is identified by its casting number, located on the skirt behind the driver's side cylinder head (just forward of where the bell housing bolts up). Also - next to the injection pump on the driver's side there is usually a serial # that starts with a letter. That letter indicates the year.

In regard to the cooler lines - I find it hard to believe - with easy use - the lack of them will make much difference. But - I have never run without them and wouldn't. Call it good insurance.

The block is identified by its casting number, located on the skirt behind the driver's side cylinder head (just forward of where the bell housing bolts up). Also - next to the injection pump on the driver's side there is usually a serial # that starts with a letter. That letter indicates the year.

In regard to the cooler lines - I find it hard to believe - with easy use - the lack of them will make much difference. But - I have never run without them and wouldn't. Call it good insurance.




OK but once I get those numbers how do I identify if it is a J code or a C code?

Thanks

OK but once I get those numbers how do I identify if it is a J code or a C code?
Thanks

Just look into the intake manifold opening. If it's wide open with no EGR ( or whatever) crap inside - it's a J code. If it has a pod with a vacuum hose hooked to it - it's a C code.

OK I have read some things about early 6.2 heads having problems cracking between the valves and something about a cooling port that was not the best design. It leaks by the head gasket or something.

What can I do to keep this running without problems? I am not asking for modifications just what kind of maintenance thing to I need to be aware of in order to keep it running?

If you take the heads off make sure you replace the head gaskets with a quality head gasket (ie. felpro) and get rid of the torque to yield head studs. I know it's scary how fast the parts add up. I've just been through all of this myself.

Just to let everyone know I will not be replacing the head gaskets. I am going by the old saying "if it isn't broke don't fix it".

I know it is easier out of the engine but I will take that chance.

If you take the heads off make sure you replace the head gaskets with a quality head gasket (ie. felpro) and get rid of the torque to yield head studs. I know it's scary how fast the parts add up. I've just been through all of this myself.

You are certainly correct about how stuff adds up fast. That is why, over time, I get more and more reluctant to pull things apart - unless it is absolutely necessary. And - I've worked over the years at two Chevy dealerships, one BMW dealership, and three John Deere dealerships. I have seen SO MANY updates and alledged "improvements" that failed, I am skepical until something proves itself to be good. Case in point is those 350 diesels in the late 70s. GM told us, over and over, that the newest "computer designed" headgaskets and special new bolts would fix the problems, and they absolutey, did not - at that time. As I understand it - later engines - especially Goodwrench replacements - were pretty good - but at that point - we were all onto 6.9 IH Fords and 6.2 GMs.
And now?? Trying to figure out who has good parts? Big name brands and high prices do not always equate to good quality anymore.
I don't have any good answers to all this. I guess you make your best "guess" based on whatever knowledge and experience you have - and go with it. At least with the Internet - much more info is available to anyone - which is quite different than things were in the 50s-60s-70s. But, there is the added problem of sifting through all the nonsense that is posted and figuring out what is actually good useful info. That's why I read these forums.

Some people have a shortage of sense of humor. Well I was Wrong, They don't all crack. We've taken apart at least 100 6.2's & found at least 3 good ones. 2 happen to be 82's & one was an '87. So your right that they all don't crack. There is no particular reason that some of these break that we have found with relation to miles of used hard or any other reason we could find. We have found a high amount of broken mains in any year.

Still working on getting the engine in.

It looks clean inside. I am installing a stud girdle while I have it out of the truck, as well as all new seals on the bottom end.

As I said earlier I do not want to put new head gaskets on, I want to try to keep expense to a minimum. If I pull the heads wll have to take them to the machine shop and up and up the expense goes. So I will not be able to look in the cylinder. Is there any way to check compression while it is out of the truck? Or should I even wory about it with only 90K miles on it?

Thanks

Still working on getting the engine in.

It looks clean inside. I am installing a stud girdle while I have it out of the truck, as well as all new seals on the bottom end.

As I said earlier I do not want to put new head gaskets on, I want to try to keep expense to a minimum. If I pull the heads wll have to take them to the machine shop and up and up the expense goes. So I will not be able to look in the cylinder. Is there any way to check compression while it is out of the truck? Or should I even wory about it with only 90K miles on it?
Thanks

You can pull the injectors or the glow-plugs to check compression. You didn't mention if you have any history on the engine - do you know and/or trust the past owner? If not, a good compression reading will tell you if something is bad - but won't tell you absolutely if all is good.
When you have the oil-pan off - you can turn the engine over and see the cylinder bores from underneath.
In regard to head-gaskets - I assume since it's been mentioned, someone's had a few problems. I have never had a head gasket leak on a 6.2 except for my 1982s. They were prone to it - due to a port that needed plugging - GM had a kit of fix it. My later ones have never bothered - even my 87 that made it to over 500,000 miles. But, I pull my injectors every 100K and check and/or replace. A bad injector can cause excess pressure on a head gasket due to hydrostatic pressure.

You can pull the injectors or the glow-plugs to check compression. You didn't mention if you have any history on the engine - do you know and/or trust the past owner? If not, a good compression reading will tell you if something is bad - but won't tell you absolutely if all is good.
When you have the oil-pan off - you can turn the engine over and see the cylinder bores from underneath.
In regard to head-gaskets - I assume since it's been mentioned, someone's had a few problems. I have never had a head gasket leak on a 6.2 except for my 1982s. They were prone to it - due to a port that needed plugging - GM had a kit of fix it. My later ones have never bothered - even my 87 that made it to over 500,000 miles. But, I pull my injectors every 100K and check and/or replace. A bad injector can cause excess pressure on a head gasket due to hydrostatic pressure.

I guess what I was asking is can a compression test be done while the engine is out of the vehicle? Do you turn it over by hand or what. I have never done a compression test on a car motor before just small engines with pull or kick start.

Hook the starter up to a couple of batteries on the stand & crank it over to check compression.

29937

29938

Cracked Block

29939

Close up

29940


WOW:grd:

Thats a clever crack indeed.:eek:

Wow... That is quite impressive. Wonder what caused that...

Those cylinders are pretty rusty. :eek: Makes me wonder how much antifreeze was in the coolant...

Well, that engine block is still worth about $25, anyway... With scrap prices as high as they are... :cool:

They are rusty because we had a very humid day after it was taken apart and it was in the back of my truck. They were not this rusty when the heads were pulled.

That's a pretty serious crack. I've never seen one in a cylinder wall like that before.