I have a 92 pick up truck with a 6.5 turbo engine in it. It has 200,000 miles on it. It is completely stock. I was always dreading that I would someday have to be in this situation as far as asking for major help. I live in River Falls WI. and I went to the post office and when I came out and started driving away something let loose. Its like the motor started shaking all over the place and no power. I think I have a rod break? Timing chain let loose? Or that harmonic balancer go bad. I was able to limp it back into the post office parking lot and shut it down. Oil pressure seems fine. I popped the hood and then started it back up and went out to see if I could see anything unusual. I didn't other than the engine was making noises and jumping around. Another thing that I seemed to notice is that when I shut it off the motor seemed to stop immediately. I have been reading this forum most everyday and have learned alot. Every one seems to be real helpful. Now I am the one that needs help. Hopefully it won't be to expensive to fix. I am keeping my fingers crossed but always fear the worst. Please help me.

Hey Doober......always expect the worse when you drive a diesel.....they just plain cost alot to fix. I just LOVE them!!!

Any water in your oil...holes in your oil pan...leaking from bottom of the truck?

No oil under the truck. The truck is still at the post office. I got a ride home. I will go and check to see if there is water in the oil. Thanks.

is it smoking white alot out of the exhaust? if it is and the motor is shaking really bad you may have lost a cylinder. You should take a 19mm wrench and with the truck running crack open all the injector lines until you crack one open and you notice you change then you found your problem.

No white smoke at all. Another clue is that a few weeks ago when I would start the engine up cold the engine was alittle more noisy. I thought it was because we were have -20f here. the noise would go away when the truck warmed up though. It almost sounded like there was a knock. I thought mabey it was a exhaust leak making that knocking sound. It would go away when all warmed up.

How long ago did you fuel up before this happened? Maybe you got a batch of bad fuel.

Nick

Hmmm, I fueled up mabey acouple hundred miles ago. I think the 8th of Feb. was the last time I filled up.

I am going to have my wife tow me over to a heated garage that I have that is only a few blocks away from where it is sitting. Would a lift pump cause these symptoms. I have replaced them a few times but never caused it to make that much racket. The last time I was this scared was when I put new heads and gaskets in and started it up and it made all kinds of noise. But I think that was just air. This makes more noise and the engine just shakes. Fuel or timing? Or what? I think one would call this a opportunity. I will also put on a new filter. I have been using diesel service additive religiously. I wish she would get home from work so I could go get checking some of these things. Harmonic balancer, would that make it shake so bad. It was like a snap of the finger, bam , I was stunned. Help.

at this point you need to follow along with what z79 was saying. 19mm wrench, start the truck up, and crack the injector lines one at a time, until fuel starts coming out. If the motor changes then you found a decent cylinder. If you crack one open and nothing happens then you found a cylinder that wasnt doing anything. If you crack all of them and they all test good, then you probably lost some of the nylon keepers on the rocker arms. If one of them tests bad, then first verify that fuel is spraying from the line, if so then the IP is pushing fuel to it, good. After that do a compression test on the bad cylinder. If it does have compression, and fuel, but its noisy, then its most likely an issue on the valve train, such as the nylon buttons on the rockers.

May also be something as simple as the optic sensor slipped or is going bad. You'd have to check that with a scanner that displays the timing value. Basically anything from -.25 to -1.94 TDCO is in a good range. Factory is -.25 to -.75, lower than that is fine too, down to -1.94. Generally speaking lower is preffered for power anyway, but too low will cause one hell of a racket.

ok, but I am afraid to start the darn thing up. It sounds bad. Is there anything else I sould check before running the engine? I just don't want to run the engine and risk damaging it if there is something else that is wrong that would cause engine damage.

well, first thing would be to check all fluids. Make sure everything is full and not contaminated. Also wouldnt hurt to take the serp belt off and make sure all the accesories are spinning properly. Might get lucky and the noise be something driven by the belt.

wouldnt hurt to try and get a look at the engine mounts and make sure one didnt come apart.

Okay, thanks Scruffdog, I will take surpentine belt off and see what happens. and check all fluids. Great Idea. That could be why it seems as soon as I turn the engine off it seems like the pistons stop very fast. This is a F motor if that helps.

Okay guys, just another idea to kick around. This truck is a five speed manual. Would that duel mass flywheel cause it to jump around and act like it is out of time?

I'm with Scrufdog, prolly a rocker arm keeper or bad injector(when they stick open they'll sound like a rod knock crossed with a lifter knock and hammer really loud), check your balancer and accessory drive balancer, when the accessory balancer goes bad they'll kinda hammer at idle, when my harmonic balancer went bad it ran ok at idle just vibrated at the higher rpms.

How bad is you engine shaking, none of the things I mentioned would make it shake real bad, just sound awful.

When you shut it off was there an abrupt clank, if so check the accessory balancer first. Is your truck a 5 speed, if so does it still have the dual mass flywheel?

yes it has the duel mass flywheel. Do you think a spring broke on that?

if the nylon keepers have gone on an exhaust rocker,. it would 'thump' pretty hard, nowhere for the compression to go,.and it would make a popping noise thru intake as well,.shake real bad too,.fire the motor back up, and really listen to it,. a rod knocking really sounds bad, so does a piston,. a broken piston won't affect oil pressure but will usually pour blow by from the valve covers,.so now you have a couple of more idea's to look at,. if oil pressure is good,. i,d let it idle and try and pin point the area of the noise,.
good luck!
nick

I had the same symtoms a couple years ago. Just cruising around 20MPH it just started running very rough. I stopped and started it a couple of times, it was still running rough, then out of nowhere, at idle, if sounded like the engine was coming apart. It turned out to be one of my nylon buttons on the rockers. When they break the rocker arm will slide off the push rod and now the push rod is loose, flopping around inside the head. Well it found it's way down an oil journal and the skirt of my #1 piston proceded to chew it up. It was curled up in the shape of a "6" half inside the piston. Anyway, given the miles on your engine, I would suspect this nylon retainer button.

also, if ytou start it up, take off the oil cap and see if it is puffing like a frieght train out of the fill tube.

Okay guys, two years ago I replaced the heads with heads that had 24,000 miles on it. How I got the heads was a coustomer had put in a brand new motor from gm. heads and all. this guy had a oil line come off and ruined the bottom end of the motor. GM sent another motor and did not want the heads back. so the mechanic kept the heads and then I came along and bought the heads from him. I got the rocker arms and push rods also and used the newer ones. But I suppose it could still be a button that fell off. I just don't want to ruin the engine by running it if it is a button issue. What do you guys think?

I suppose I could get a few five gallon fuel containers and open the "T" up in front of the engine and let the lift pump push out all the fuel in the tank and try different fuel and change the fuel filter also. Keep the ideas comming. I really appreciate it. Wife should be home from work any time but I will be back as soon as I get it in the garage to see other ideas. Thanks Everyone:)

could still be the problem, but less likely if the buttons are that fresh. Check everything you can without starting it. Write this stuff down if you havent already so you dont skip/miss something

Dual mass flywheel, I cant remember how they act when they go bad, but if it got off center it could really make it shake.

The symptoms described make me think fuel or timing, and I'm no expert.
What about the dowel pin on the IP gear shearing off? Didn't this happen to someone here recently and they thought the truck threw a rod?
Or maybe timing chain took a dump? Just throwin' ideas out there!

All these ideas are great. Thanks and keep them coming. We are supposed to get 14 inches of snow here this weekend and it is my Plow truck. Well I guess its time to teach the wife what a shovel is for. Just kidding.:D

I wish I would have put in a new timming chain when I did the 97 cooling upgrade. I didn't even think about it until I had it all put back together. If it was the timing chain could I ruin the engine if I ran it? I think i would. Darn I just don't want to do more harm.

Did your SES light come on at all? Do you have a way to check codes if it did?

92-93 wont throw any codes, manual IP.

I have checked codes with my 95 suburban 6.5 with the paperclip. But I don't think I can on the 92? Please help. I do know someone with a obII reader. He has checked codes on my duramax. I wonder if his tool would work on my 92?

92-93 wont throw any codes, manual IP.

AHH...see the importance of fillin' out your signature?

I didn't realize it was a 92 till you posted this. I saw '97 on a post and thought....

yes I need to fill out my signature. I will do that soon. Sorry.

Okay, Got the truck over to the heated garage and brought the wife home. I am going back over there in a bit to start checking things out. Any other ideas?

If you had alot of white smoke with the heavy vibration, I'd say you may have a busted rocker retainer(dang cheap plastic piece that will scare the heck out of ya), and will literaly drop a rod(fortunately in my case with no major damage).
Just a thought.

Mark:beerchug:

But I don't have any white smoke. It is just hammering and the motor is jumping around. When I tried to listen to the motor I really couldn't hear where it was coming from. It was like all over in the engine compartment. Would a injector cause this? I probably have just over 100,000 miles since the last injector change. Would the injector cause the engine to jump all over the place.?

if i disable a fuel injector on my truck the motor sounds slightly labored but doesnt shake around and make a hammering noise at all.

if i disable a fuel injector on my truck the motor sounds slightly labored but doesnt shake around and make a hammering noise at all.
Like scruf said,
During the diagnostics of my problem(as mentioned above), we found one injector that was loose, corrected that problem and it did not cure it, mind you this is just after I had all the new injectors installed, as well as the IP, water pump, glow plugs and many other items and it turned out to be the stinkin plastic rocker retainer cap. Hope you get it found soon and fairly inexpensively.

Mark

But I don't have any white smoke. It is just hammering and the motor is jumping around. When I tried to listen to the motor I really couldn't hear where it was coming from. It was like all over in the engine compartment.


This is how I would describe how my truck was running when I bought it. The crankshaft was broken with a horizontal break so it would continue to push the other end on around. I was able to turn the flywheel easily about 1" either way without the front crankshaft pulley moving. The engine would start up clacking & shaking and the truck would idle and drive around the yard.


Yea, I bought it that way and still don't regret it.

Howdy folks!
This is my first time on the forum and first post. My name is Greg and I go by the call name Sodbuster, I live in mid Missouri @ happily married with two kids.
I am a mechanic by trade and a home improvement contractor.
My destiny is mud boggen big bore 4wheelers in the thickest, nasty-est, peanut butter mud I can find. My son and I follow and compete in mud run competition through the spring and summer.We love it with a passion, we have a common interest 4wheelers and getting muddy. The reason I have joined up on the forum is a good friend of mine Doober has got problems with his rig. I have never met this man in person but I have bought many parts from him on Ebay and I have got to tell you He is one hick of a straight shooter. Doober has saved me hundreds and maybe thousands of dollars on parts for my 4wheelers and I just wanted two jump on this form and try to help a good friend.
Now lets get on with the show....... Doober my friend Howe the heck are you! When I spoke with you on the phone last night we had talked about this problem you are having. Ok I don't no what you have come up with since are last talk but I have read all the post`s and from what I have read there is a ton off really good info on this thread. Do your basic check's first and you no what they are, then go with what Scufdog said check your injectors one by one and make sure that you got fuel. also you need to pull the valve covers and make sure them rocker retainers are not trashed like Kimagine spoke of.
It is like 1:00 here and you have not posted since this morning so do these check list first (you may have all ready done ) and chime in and let us no what you come up with. Ok bud good luck to yea!!!!!

:welcome2: Howdy back at ya Sod B.

98 5.7 1500 truck ??? hey AFIK they didn't put no 5.7 in them, you ain't one of them Gasser guys that done sneaked in under the radar :eek: :eek: :eek: well welcome any who; always nice to have another gear head in the crowd regardless of the flavor.

this is a good place to hang out if you have a ailing GM 6.2/ 6.5 tell your friends, we got some regulars that post here that like to help each other out, hobby for some passion it seems for others. Pretty good crowd we mostly deal with lek-tron-ic IP'd 6.5s, but can work our way with mechanicals also.

Crank problems don't care what IP is on em unfortunately, and happen with some frequency on the 6.2/6.5 if pushed too hard (not ready to make that call yet Doober do diagnostics 1st guys mention previously).

Hey, First off I would like to say to everyone that this fourum is the greatest. Everyone is willing to try to help out a fellow diesel owner. And I just love that. I feel like this forum is like family. My experience on other forums like snowmobile forums is that some times you get help and sometimes you don't. Not this one, It's like a job that you love. I read this forum on a daily basis. unfortionally, for me, I am the one having the problems. But I am at the best possible place that I could be for receiving information about diesels. Thanks Everyone, you are all great. Also, Sodbuster. Thanks for coming aboard. This Sodbuster is one awsome honest guy. He is big into 4-wheelers and making them perform like no one else can.
Now, back to my problem :( . I stopped at acouple of garages and acouple of parts stores and shared with them my problems. I then, buy using your guys imput went and started the truck back up. It again, of course, made alot of racket. It sounds terrible. The engine even moved around abit. I changed fuel filter and made sure the lift pump was working. It still sounds like a real bad rod knock. I then took off the oil fill cover and found that it is different than it used to be. It looked like a train. The smoke coming out of the oil fill wasn't constant. It would have a push of smoke coming out then back to normal smoke. Realize this was happening in a matter of a second. But there is a definete push of smoke coming out of there probably caused by one of the pistons. Is the piston cracked allowing air to pass by it causing the burst of smoke? Or is it in the rocker cover with the rocker arm not opening up the exhause valve and the pressure is then pushed around the piston into the crank case? No remember there seems to be some kind of hydro lock or something because it is hard to start. It turns over alot harder than it should. Is the exhaust valve not opening causing this to act like a hydro lock. Also when I shut the noisy, jumpy engine off it stops right now. It acts like the engine freezes instantly. Then I try to start it again and the starter definetely has to work to get it to work.

Hey Terbine Doc
98 Was the last year for the 5.7 in a full size pick up.They also put the 5.7 in the Sub in 99 (special order).
I would have me a diesel in a hart beat if it wernt for $2.20 a fricken gallon.
I use E85 and right now it is at $1.60 a gallon, my truck is not a E85 truck but i burn it just the same. We have Bean brain washed by our government in to buying high dollar oil wen we don`t need it. Ethanol and bio diesel is here and we need to push it big time. If you have axes to it yous it and don't let any body ever tell you it well harm your vehicle. Anyhow thanks for the welcome mat and well talk some more on this subject.
Hey Doober what did you find!

Wasn't disin ya hope it didn't come across that way, 5.7 was a a Diesel long time ago also weren't one of GM's bettter ideas tho, I was trying to assertain if maybe you had done a swap.

Mpg-to power is where you sort of make up for it if you own a Diesel long enough; and until Diesel community started "going green" Diesel vs gas prices were on par.

Up untill 2 yrs ago "and Green movement needing another cause", after messing with gassers had run it's course, started messing with Diesels, Diesel around here was less than gasoline.

Back to Doober, check out this thread Doober http://www.dieselplace.com/forum/showthread.php?t=84008, look close at the crank balancer pics, are you 4x4 or 2wd, might be worth dropping the pan, there are some bottom end issues with the 6.5, easily found on 2wd vs 4wd. I would not run any more than I had to with klunking going on until I dropped the pan

Ok I just made a post and now it is gone into lala land.
Doober sounds like you may have a bent push rod or a rocker arm that is not opening and closing a valve. This may be the reason for the blow by wen you opened the oil fill wen it was running. Remove the valve covers one at a time and check for full range of motion with no slop. dang it I wish we lived closer I would do it for you, I need something to do.

Doober we need to quantify blowby wispy smoke vapor or full flow blowback back in your face (FWIW I've never been very good at adding oil on a running 6.5 I tend to wear more than what goes in);

On the 6.5 Diesel some vapor from the oil fill tube is normal, as is some oil in the intake/.turbo, part of the 6.5s crank venting system, some things we would think as bad bad on gassers don't necessarily equate on a Diesel as bad.

This one since it is making some metalic noises is going to require you getting under the hood and opening up those places where metallic bumps in the engine could emmanate from.

If you've done the easier checks other members have recommended, time to get out the tool box top or bottom looks your choice; pull off valve covers, nothing there, pull pan, could have a look under the trans dust cover or starter area, for things that go bump in the night.

Unfortunately we aren't there and could burn up tons of "tron ink" guessing what it might be from afar. As soon as weather/time permit you need to roll up those sleeves & :grd: have camera close by keep us posted with what you find and we can help you from there.

Bottom line you have clunks, and engine is slowing to a stop unnaturally so generally in the 6.5 world that means something mechanical is amiss, only way to know what it is zactly, is to do explorative disassembly.

sounds like its time to take off the valve covers and check the rockers.

Doober, if you suspect hydrolock then first pull your glow plugs, have someone crank the motor, and see if one of them blows out a lot of fuel. If one does, then at least you know what cylinder to look at (might save some work). If you are by yourself then try one at a time.

yea, I think it might be time to pull the covers off and see what if anything is going on with the rockers. I picked up some grey engine sealant from the stealer Today. Keeping my fingers crossed that I find something in there. And hoping I didn't ruin anything. In a way I like doing things like this. It is like going to school. Like when I put new heads on and head gaskets. I can now say I did it. Some of my friends said that they wouldn't even consider doing it. They would take it to the dealer and spend alot more. Also I feel that when I learn something like this I will beable to help my son when he has a problem some day when he gets older. Then I will beable to just point fingers and tell him what he needs to do. Thanks guys and keep the ideas coming. Hey, I am going to talk my 13 year old son into using the camera and try displaying it as a video. I will be back.

Hey Screws, Thanks for the reply. But I mabey stated it wrong. I guess I really don't think it is hydrolocked, but am leaning towards the exhaust valve not opening when it should and causing a lock like that if that sounds possible? I don't know. I am just guessing and trying to figure out why it seems to lock up like that. I will try to get a video tape with audio up so everyone can hear it.

if it was a broken piston,. the engine wouldn't "stop" you are describing a cylinder that now has 2 compression strokes and nowhere to get rid of the power stroke gasses,.so those gasse are trying to find a way out somehwere, be it back thru the intake a little,. past the rings and into the pan etc,. and that would give you that 1 huff of smoke, then gone, then a huff of smoke, etc, coming out of the the oil fill cap,. broken pistons make a solid stream of blowbysmoke from everywhere! :D (btdt)
best of luck,.
nick
ps your low mile heads might have been outfitted with high mile retainers,?
exchange rebuilt heads usually use the original rockers etc,

http://www.youtube.com/watch?v=2Az55poVBxs

Guys, i got my boy to vidio my truck. What do you think?

sounds like its popping through the intake, which would lean towards an exhaust rocker being off

When you pull the valve covers off and find the bad rocker arm holder(what ever it's called) buy all 16 and change them all, that's what I did. They are cheap and will help down the road so no others will go out that sson.

Mark

Okay guys, thanks so much for the help. As far as the 16 rocker keepers? Would they be the nuts that hold the rocker on? I know I have to take it apart to first see if that is the problem. But I hope we are onto something here and going in the right direction. Thanks again everyone!!!

They are little plastic push pins that secure the rockers to the rail. Once you take the valve covers off you will see. Pretty cheap part, you can get them at the dealer. The part number for them is in the part point sticky.

Damn that don't sound good!! Wish I could offer more help. Good luck.

Nick

Okay, Thanks Tarama. I will look and see what I can find. Yea it does sound bad. I brought the camera over to my dad's house and played that video on his televesion. He could hardly watch it. He kept saying shut the tv off, I seen enough. I kept the tv running and he looked at me and said what is wrong with you. He didn't like the fact that I keept it running that long. But I wanted one good shot for everyone to look at. If I would have only run it for five seconds mabey the clue or noise wouldn't have given anyone a idea to what the problem was. It won't be run again. I just about crapped my pants when it went. People across the street from where I shut it off even turned and looked at me.

Hey Doober, what state are you located in?

River Falls, Wisconsin :)

Update. I went to visit a friend that is really up on diesels. He thought after showing him that video with the sound clip that I had a broken crank. We set up a time to meet at the shop where I have the truck. I had the valve covers off and all looked okay in that area. He then was looking for a timing mark on the front of the engine. He asked me to hit the starter just a bit. He then said I don't like what I am seeing. He then asked me to turn the motor over one revolution. After I turned it over he backed up from the front of the truck and said you have a broken crank. He wanted to show me so he cranked the truck over while I looked at the harmonic balancer and the outer pully. It wobbels really bad. So I am out of luck. Cheapest 6.5 I can find is 6,200 from gm. Even though the truck is in excellent shape I don't think I can justify the cost for a 92 pickup truck. Any Ideas?

In my constant Ebay searching, there is a local guy selling this 6.5 block.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&sspagename=ADME%3AL%3ARTQ%3AUS%3A1&viewitem=&item=220086387806&rd=1

I sent him a note asking about the crank since it isn't listed. He said that he does have it but it would need to be turned down due to the spun bearing. I am looking just to keep spare parts on hand if they sell cheap enough. There are 2 other cranks listed right now also.

* IF * the block isn't damaged or cracked, this could be a cheap relatively quick fix to get you back on the road.

I did this complete process a couple of years ago for a total cost of around $600. Included:

Timing chain & gears
oil pump
reground crank & bearings
harmonic balancer

Good luck.

6.5 cranks can't be turned, if worn they are scrap, I'd be real careful about a ebay block, definately Id want some close up pics of main webbing, 2000 model no crank, only 15K miles something is amiss here, possibly that one busted it's crank also and depending on how fast it was running when the crank blew very likely there are main cap issues

6.5 cranks can't be turned, if worn they are scrap,

I've heard otherwise...

I've heard otherwise...
I'm with you on this one, We have turned varios 6.2 cranks & a couple of 6.5's & so far no failures.

6.5 cranks can't be turned, if worn they are scrap, I'd be real careful about a ebay block, definately Id want some close up pics of main webbing, 2000 model no crank, only 15K miles something is amiss here, possibly that one busted it's crank also and depending on how fast it was reunning when the crank blew very likely there are main cap issues

Mine was turned... 40,000KMs and counting running 8-10hours a day 5 days a week (a tank of fuel every day and a half) so I likely have twice the mileage.
I heard before that they could not be turned, but the machinest assured me that the crank was nothing special and had NO special coatings

Some GM cranks in the past were not hardened deep enough for more then
(-.010) such as the ones used in the 1969-70 Pontiac 400 blocks. All we had to do was turn it down as needed then send it out for nitrate treating if I remember right. Never had a problem after that & it did not cost that much at all.
That may be an option to ask about before giving up on a used one.

Update. I went to visit a friend that is really up on diesels. He thought after showing him that video with the sound clip that I had a broken crank. We set up a time to meet at the shop where I have the truck. I had the valve covers off and all looked okay in that area. He then was looking for a timing mark on the front of the engine. He asked me to hit the starter just a bit. He then said I don't like what I am seeing. He then asked me to turn the motor over one revolution. After I turned it over he backed up from the front of the truck and said you have a broken crank. He wanted to show me so he cranked the truck over while I looked at the harmonic balancer and the outer pully. It wobbels really bad. So I am out of luck. Cheapest 6.5 I can find is 6,200 from gm. Even though the truck is in excellent shape I don't think I can justify the cost for a 92 pickup truck. Any Ideas?

something doesn't add up here for me,(but then again maths not my strongest subject) a broken crank that will still run? only place i can see that happening is if the snout broke off like was common with tire trucks when they ran a compressor off the crank snout,.if the crank broke any where else the back half would turn on the starter and the front half wouldn't,. the front half has the timing chain etc,. so cam wouldn't turn neither would the IP, so methinks you may have a harmonic balancer issue as well,. do the belts still turn?? It still runs, so i don't subscribe to the busted crank theory,.
'course i could be wrong,. my wife will tell you that much.
nick

Hey Phantom, Thank you for your input. I called the mechanic and told him about what you had thought. And now he has put me back to work. He wants me to pull the radiator out and Get the stuff out of the way so he can get at the pulley and harmonic balancer. You got him thinking now. Which is great. He said " you don't think that key sheared off, any thing is possible". At first he said, " Well you seen the front pulley the way that thing wobbeled on there". I also told him that if the front of the nose of the crank was busted mabey the block isn't junk, as far as the weebing is concerened. Mabey there is some hope for me yet:o: . Keep the great ideas comming.

I've have this project 6.2 to 6.5 build on the to-do list for a while one reason it is "on hold" is for want of a crank, 3 different machine shops, "those can't be turned", but maybe it is because of the power envelope I'm pushing for, so those of you that have turned them I'll defer to your successes.

Doober it is possible your damper may be the culprit and crank is intact, but rather than have us all guessing what it might be, drop the pan, we aren't there so you have to be our eyes, our ears from the vid clip say something ain't rite :eek: :eek: :eek:

Here is a picture of how the crankshaft can be broken,but still turn both halves and the truck can still run.

34788

The red line through the crank indicates where the break is, and since the main caps hold both halves in place, they will both still turn together depending on which section of the crank is providing power at that moment.

If that makes any sense at all.

Hey Phantom, Thank you for your input. I called the mechanic and told him about what you had thought. And now he has put me back to work. He wants me to pull the radiator out and Get the stuff out of the way so he can get at the pulley and harmonic balancer. You got him thinking now. Which is great. He said " you don't think that key sheared off, any thing is possible". At first he said, " Well you seen the front pulley the way that thing wobbeled on there". I also told him that if the front of the nose of the crank was busted mabey the block isn't junk, as far as the weebing is concerened. Mabey there is some hope for me yet:o: . Keep the great ideas comming.

HMMM<. mebbe your mechanic is a busy man and pre-occupied with other things,. if the crank broke in front of the timing gear i,d say the end piece would fall off or at least you'd be able to wiggle it out from the seal,. and if the belts are still turning,then it's not broke right?,. I,d leave the rad in for the minute,. seems to me he giving you things to do to stay out of his hair for a while,. ( i do the same things to my kids, "go watch for icebergs honey make sure they don't hit the house")
Now,. you say all is ok under the valve covers,. did you roll the motor over on the starter and watch each and every valve to make sure they are indeed working? did you place a hand on every rocker and give them a firm push from side to side? did you remove all the injector lines to get into the valve covers? (i hope you marked your lines for re-aasembly,)
If indeed all the valve train looks tight,.there are two ways i,d go about it now,.1st would be a compression tester and find out which hole is sick,. or 2, put up with the noise,. let it run and as was stated before crack injectors to see which hole is the problem (noise should lessen when you find the culprit) mebbe borrow a laser digital thrmometer and shoot each cylinder right at the head while its running,. you'll likely find 1 much cooler than the others,. Thats the way i check for bad injectors in the big trucks,.
nick

We've had two of them break in the first rod journal & drove in still running & the balancer flopping like a fish out of water.

Not on a diesel but on my Ford F250 my harmonic balancer let go and the engine acted exactly like that. New balancer and I drove it away fine as kine.

Okay guys, Change of direction. I called my friend, Mechanic, back and discussed it with him. I think I am going to pull the oil pan off first and see what I can see there first. He was okay with that. But did tell me that that radiator is going to have to come out of there sooner or later anyway. He is still doing the math and thinks it is the crank that is broke. Any more input? Keep it coming. This is great.

If the Balncer is Flopping she's broke & probably the block too. ( No sense sugar coating it)

My '93 sounded and jumped around like yours. The crank was broke like the picture. After sitting a couple of weeks, you could also see the cracks in the block. It had 195K miles on it. I got a Goodwrench engine at the local Chevy dealer for $3,800. 50K warrenty. The parts guy sells to me at wholesale. You need to check and see if any friends can get wholesale pricing at your dealer. I changed the clutch and flywheel while it was down. The replacement flywheel is one piece.

We've had two of them break in the first rod journal & drove in still running & the balancer flopping like a fish out of water.

I can't understand how a crank with the snout broke at #1 rod journal could still turn the timing chain, there's a fair bit of strain to turn the cam and the IP,.;) and #1 main is between between the rods and the balancer,. so i call bullsh!t on this one,..

When it breaks in the first rod pin it jams against the throw arear enought o spin it all. I Seen it & I'm not the only one. If I had a decent way of drawing the picture to show you I would but there is no bull here & if he was we wouldn't allow him to $hit you.

Okay fellers mind your manners no need to get everybody up on rev limiter, 309 the bs call wasn't warranted, you may think it to your hearts content but you don't need to share your opinion quite that way, civility is the watch word, we can disagree just have to be civil about it. KP/309 point & counterpoint made, lets let it go at that.

Doober you have us all on edge of our seat waiting for what you find out

Hey Turbin Doc, Thanks, and I will be digging into this motor shortly. I just have a little imput to the last few posts. They are good posts but keep in mind that this is a learning experience for me.

TD edit, no problem, BTW paragrahs are allowed, makes it easier to read ;) we don't grade for grammar, but do like an easier read, remember you are in Jurassic Park, where the older Diesel dinosaurs roam, and somewhat older drivers reside, so some of us even have/need bi-focals

And I think that this is going to be a learning experience for all of us on what we find out about this motor, as far as what the problem is. I am very open minded on everyones posts here and appreciate all the help. I just have some input on what my friend, the mechanic, has said. He said that he has also seen the engine run with the crank broke.

He also knew exactly what ShawnR was talking about when he said that the main caps could hold both halves of the crank in place allowing the cam to operate the valves therefore allowing the motor to run. He, the mechanic, is leaning towards the crank being broke but isn't rulling out the possibility of the harmonic balancer shearing the key and breaking either. And yes my friend, the mechanic, is a very busy man, but no, he would not have me go looking for icebergs.

We are in the middle of a blizzard and now that I don't have my plow truck I have been having to go around to my rentals using the snowblower to allow my tennants to get in and out of the apartments:( . So in a couple of days I will be pulling the oil pan and start there. I will then get back and let everyone know what we find.

Between everyone here at the Diesel Place and my friend I know we will get it diagnosed correctly. I couldn't be in better company.

Thanks, Everyone, for your help and keep the replies coming. Also please keep ears and eyes open for a donor motor. Just in case I need one. The Doober:) .

309 the bs call wasn't warranted, you may think it to your hearts content but you don't need to share your opinion quite that way,


methinks it still is,....break in a main, i'll buy it,.(cats are famous for that,)
break a rod pin? simple,.. motor stops,.
your move.

If I could figure how to draw this I would but I Ain't that smart so i'll try to describe it better & My description of rod pin I'll admit is to vague, so here we go. The flat part of the throw that connects to the pin is the weakest mostly cause it's the thinnest. The flat throw that goes from #1 rod pin to the second main breaks off horizontaly.(actually about 20 degrees from horizontal)
it breaks from inside of the rod pin area across the flat throw where it is 1/3 as thick as the pin itself. Because the break is horizontal instead of vertical the rod pin is still driven by the flat break that jams against the other part of the flat break. because it usually breaks at 20 degree or so angle it pushes the crank longer horizontally & usually screws up the mains in the block at the same time. Hopefully this long saga helps to explain the confusion encountered in this thread.

Yep - people have driven part way across country with that particular break, just a little more noise than normal, on 1\2 pin to 2nd main, or 7\8 pin to 4th main.

In one case, initial symptom in front was excessive harmonic balancer wobble - attempted removal of 'balancer revealed actual failure.

That could be what has happened. Horizontal break that is. My third post on this tread stated that I recently could hear a knock in this motor. Although it did seem to go away when it was warmed up.

lately when I would start the motor up and go in the house to let it warm up I would find myself turning my head back towards the truck wondering what that knock was. I was thinking at the time mabey a bad injector or possibly even a exhaust leak. But a slight knock was there.

A few weeks ago I was at my sons basket ball tournament and between games I went out to let it warm up. My dad came in from having a cigerate and said your truck is noisy. I said is something wrong with it?
He said I don't think so, I think it is the cold weather causing it. It was minus 20f out but it had been running for about 15 min. when he heard it.

You see I have a 95 suburban with a 6.5 and this 92 pickup with a 6.5 so I could tell something just wasn't right in comparing the two. The suburban, I never found myself turning my head wondering what that slight knock was. Because there wasn't one.

Well when I get caught up with the snow removal and a few odds and ends I will dig a little deeper and post back so we all can know. Great job guys!!!!

doober im sure u love your 6.5 but if i was u and u do find out that your motor is junk i would drop a 12 va cummins in it u should have more then enough torque to plow and i think u will like the cummins better then what u do your 6.5 thats just my 02 i wish i could help u with your truck but i do not no crap about a 6.5 keep me posted on it i would love to learn Thanks

Yep - people have driven part way across country with that particular break, just a little more noise than normal, on 1\2 pin to 2nd main, or 7\8 pin to 4th main.

In one case, initial symptom in front was excessive harmonic balancer wobble - attempted removal of 'balancer revealed actual failure.

i think i need a picture to.. A) understand how a broken crank arm to rod jounal can stay together underpower,. even idle, the crank is a solid connection from front to back no matter how many right angle twists and turns it makes,. break the join anywhere along the line and the engine stops, period.
Now having just typed this i went on a search, this pic is of a broken crank,. you are saying that the arm is wide enough to break yet not 'skip' ? but it would only be a matter of time,.?
Hmm,. if so i may have to eat some crow here and apologise,.
http://www.dieselplace.com/forum/attachment.php?attachmentid=31216&d=1167253273

nick

Good pic - in a number of cases the engine has continued to run until that particular failure occured - three-piece suits may be popular, but not three-piece cranks.

That failure is usually associated with the three center mains caps and webbing relocating to the bottom of the oil pan with a loud crunch and sudden no rpm.

It is difficult to believe, but cases on both forums I frequent make it inarguable - odd noises in running engine, begin initial teardown procedures, only to encounter strangely loose flywheel\flexplate or loose hb\access drive pulley.

Stick around awhile - newbies like to scoff at our safe methods for power upgrading - one of'em will be happy show you how it happens.

You may not believe it but it does happen & more than one of us have seen it.

ok,. as much as i,d need to see this in person to believe it more, i'll apologise and say that i was too quick to give my opinion, and really shouldn't have called 'bullsh!t"
and thats no Bullsh!t!:D
nick

If I would not have seen this I wouldd not have believed it either, & I don't believe things that don't sound like they add up But in this case I've seen it enough that I know it does happen more often than we would like to admit.

No prob, dude - opinions can be one of any forum's major assets - particularly so, educated opinions.

Well - war zones are not any particularly outstanding example of opinions as assets, unless one subscribes to the divide and conquer concept.

This is the wrong place to discuss this but a forum is the wrong place to have any kind of war zone, nothing is gained thus it is worthless.

We had a "war room" long time ago, thankfully it is no more, OT P&R gets pretty ugly at times, which is why I don't spend a lot of time there anymore, but it comes with a warning up front, better have thick skin to enter.