Hey everybody, it has been a while since my last post but I am getting back into working on my truck after a very busy term at school.

I am going to pull the valve covers, put new injectors in, and new glow plugs (168,000 miles on original parts now) but I wanted some ears from the knowledgeable people on this great forum to take a listen to my engine and help me figure out if it is a normal sound (CLANK CLANK CLANK racket. This engine is 100% stock 168,000 miles, with the EGR blocked with a plate and the upper plenum gutted. I have yet to get gauges for it. I have to fix the leak from my EGR as well. Notice the black runs down the back & side of the upper intake.


I have some videos up on google video, here they are: http://video.google.com/videoplay?docid=-8535495599785991002&pl=true

and here is a smokey burnout with the transmission going into 2nd gear, before even moving Haha!
http://video.google.com/videoplay?docid=-3966661713322928950&pl=true

NOTE: I don't make a habit out of this smoking of tires, just thought I would test out my new camera (google video quality stinks though)

While it's cool rite after start up, put your hand on the turbo heat shield, and see if the "knock" dampens or goes away, your knock from what I hear in the longer vid is very similar to mine, been there since day one that I've owned mine. I think the shield attenuates "normal" sound from the 6.5, something that will get your attention is how much of that noise you are hearing is being generated by the IP itself, I would not have believed the noise from an IP only; until I heard an IP on a test stand.

You are right, because the guy I bought the truck from said he noticed the knock after he had the IP replaced. So maybe the truck is alright. I will put my hand on the turbo shield when i leave work today.

Damn noise!

I had that same noise in my 95, drove be crazy, engine started using tons of oil, I pulled it, haven't disassembled the orig. engine to find out what it was though.

lots of other 6.5's out there that I listen to don't have the noise, so I know it's not normal.

I don't buy the injection pump noise issue, unless it's a line touching something...

I'm not saying that noise is the IP, just noting that a significant underhood noise is IP generated.

I still haven't figured what the noise in mine is, just that it goes away with me putting my hand on the heat shield, GMCTD showed me the phenomina Nov 2004 when I was working a job over by him, I showed it to DP in Jan. when cruising by his place in Fl enrout to a job in Jacksonville.

He picked up on the noise right away, & commented many 6.5s seem to have it. I guess I'll have to worry when it goes away or changes tone.

I do agree that the IP's are noisy! I heard a DB2 on a stand once and swore that was 80% of the whole engine noise.

I really wonder what the noise is, mine changed tone and started sounding scary, so I shut it down while I still had a good block to fix.

It's a mystery...

Thanks guys for the replys so far. I am going to be pulling a 4,000 pound dry, 5,500 pound loaded tandem axle bumper hitch 24 foot TT camper around the state (Michigan) this summer and just want to make sure the engine sounds alright. The video represents it fairly well and I appreciate you guys looking at my videos. I have all the necessary towing equipment to tow the TT with.

To me, when idling it at stop lights, it sounds like it is hitting itself with a hammer in there. At speed, the knock doesn't get louder, just the exhaust note deadens the clank. I put a broom handle around various places and the crankcase is quiet. The most noise is up around the injection lines. Can anyone hear a miss, or some other noise that doesn't seem right? It might be because my EGR is blocked. Do I need new gaskets (EGR, plenum) every time I take the upper plenum off? I know i need to replace the donut gasket in the center every time. Right?

I think the noise is louder in some diesels than in others. Around my school they have a diesel work truck that has the same knock but quieter. I was studying at my desk, and heard the familiar sound. I looked out the window, and it was a newer chevy diesel, like 98 or something. I heard another one at the street corner near my school that was quiet! But as it accelerated away from the corner, a steady small stream of black smoke came out of the tailpipe (sounded plugged up to me, I like str8 pipe, hehe)

Nice smoke out. Is it stock? I could not get my to do that.

Ladukeja- your only a few miles up the rd from me if you need any help let me know

Okay that's a little different from mine you mite want to take Rex up on his offer another set of eyes/ears is handy, as they aren't "calibrated" to what seems normal to you, crank pulley look okay ???, although that's not waht i hear in the sound clip, nothing like being there sound clips hard to assertain if it's okay

Sound clip tells me it's the crank pulley.

http://dieselplace.com/forum/showthread.php?t=49608&highlight=crank+pulley

i listened to your video very carefully, and i hear it.. that kind of pingy knocking sound..

had exactly the same problem.. tore into the engine, thinking it was rod bearing or mains.. turned out to be a bad (very loose) wrist pin on the piston.. probbly had very little time before catistropic failure.. i could actually twist the rod on the pin significantly..

hence, im currently 12K into a new engine for my truck.. should be running again on monday..

Vin


Damn noise!

I had that same noise in my 95, drove be crazy, engine started using tons of oil, I pulled it, haven't disassembled the orig. engine to find out what it was though.

lots of other 6.5's out there that I listen to don't have the noise, so I know it's not normal.

I don't buy the injection pump noise issue, unless it's a line touching something...

I have to go with Diesel Pro. My 2500LD started making a funny noise. Always there, but started getting louder. Crank pully twisted and mounting bolts where making contact with the pully! Made a real nice clink at shut down. Rubber looked fine just twisted on centerline. Looking for a used replacement. If you have one you are willing to part with, please let me know.......

Bill what I've been told from most that have gone thru this already is go with new, IIRC it's a $85 part not worth risk going used I've been advised, depending on your situation that might be best for long run.

So, when I left work yesterday I put my hand on the Turbo sheild and the noise lessened, but there was still that KLANK sound. Interesting about the crank pulley. I can relate to the noise of the injection pumps some of you are speaking of. We did some tests on IP's at McLaren for Isuzu. A Injection pump test stand driven by an electric motor, hooked up to an oscilliscope and computer to measure pressures.

I really am pretty new to diesels, but the information here is the best. Thank you everybody for your sincere replys.

Thanks for the compliments, and the advice. The truck is a stock 2wd with 342 gears, 235/75R15 rubber, a straight piped pinnacle exhaust that goes 3" from the turbo, to 3.5" for about 2 feet, then 4" the rest of the way back. The exhaust hasn't moved since I put it on, which is incredible. I bought new isolators from auto value also (price was between 4 and 8 dollars IIRC). The end is angled and under the truck about a foot from the rear bumper/ fender. Low profile, hehe. No huge tips for me. I have some more videos of the turbo sounds I might post, just for kicks and giggles. You can barely hear the turbo in the video clip I posted.

Rex: Thanks for the offer, I will take you up on that, I will send you a PM :).


I hope it isn't anything serious because I just sold my baby, the black truck you see in my avatar, sold with 300,108 miles on the od. What a clean truck, and so reliable, I would drive that to California, If I had the time ;). It only needed a starter in the time I had it which was for 30,000 miles, some of which were teenage style driving -drive it like you stole it, barking the tires in the first three gears- haha what a blast.

But thanks again everybody, and Rex and I will keep you updated.

Keep the posts rolling. :ro)

Hi there,

ladukeja, does your truck clanks at low motion ?
Mine did, idling at 500~550 RPM's and was driving me crazy and scared : I was pretty sure the engine was dying and that I will soon see a piston goinf through the engine....:eek:

Then, I took out the upper intake manifold to have a look at the PMD in case of when I will get time to relocate it. Doing so I remarked that there was a lot of soot inside and notice what could be an "air leak".
I cleaned out all soot in the manifold and then carefully replaced the manifold using Loctite joint maker (the yellow one) and cross-torqued the bolts...

and then the miracle occurs:D I started the engine and had the good surprise to see that the engine was running at 600~700 RPMs with no more clanks:D :D :D :D

Not sure your problem is the same, but that was the solution to mine.

Hope that helps. ;)

Are you talking about soot inside of the lower intake manifold, matuva? Well, when i gutted my upper intake, i thought of taking off the lower one too, because of all that soot! But I left it alone. The outside of the manifold is clean, except for that spot around the rear of the egr in the video. Hope I didn't hog too much out. I took all the metal out to leave only the center boss, and I sanded all the rough edges smooth. I replaced the inner mystery gasket as well when I was in there (truck didn't have one when i pulled off the upper intake.

I noticed that my truck knocks more (different knock than the CLANK CLANK sound) when I put the Power Service diesel treatment in. Actually sort of like a cummins knock, so maybe that knock is normal. There is lots of noise coming from the engine compartment, it is hard to diagnose and I appreciate your help.

Everything is original but the blocked EGR, a new IP from the previous owner at 125,000 miles, and the 4 inch exhaust. I need an air filter bad, too. I was thinking about an amsoil one.

I've got a high pitched knock coming from the turbo side, been there since I bought it. Since when I've had the heads off, new injectors, new IP, new valve in one of the heads because it had a crack in it, I was sure I had the problem fixed when I found the valve, it's not quite as bad but it is still there.

I saw that all soot in the lower part too but I let it .... not enough time this day... I just cleaned the upper part and carefully, made sure that gasket + joint past will not allow any air leak and there it goes... that was 3 months ago and it's still quiet untill today

Nice burn out!!!!!!!!!

I've got a high pitched knock coming from the turbo side, been there since I bought it. Since when I've had the heads off, new injectors, new IP, new valve in one of the heads because it had a crack in it, I was sure I had the problem fixed when I found the valve, it's not quite as bad but it is still there.

wrist pin...

been there tried that.. bought the new block...

turned out to be a bad (very loose) wrist pin on the piston.. probbly had very little time before catistropic failure.. i could actually twist the rod on the pin significantly..

Ok, I can't let this one go.

What kind of a piston to pin setup does the 6.2 and 6.5 incorporate?

The right answer would be a full floating piston and pin design.

Unlike the small block GM engines, the piston is supposed to float on the wrist pin (hence the retainer C clips on the ends) and the rod is supposed to be able to move freely on the wrist pin in between the pin bosses in the piston. The SBC engines have the rod stationary on the pin, and only the pin moves in the piston from side to side. That's why on SBC engines that the machine shop has to heat the small ends to enlarge for a quick insertion of the pin.

Using full floating pistons and pin is a racing engine technique, frees up friction and allows the piston to move more freely on the rod to which it is attached.

Now, I'm not doubting that the knock in these engines associated with the clacking sound could be a loose pin busing. This could very well be so, but the only way to really tell is going to be to:

-Examine the piston pin holes for cracks
-Measure the bushing on the small end of the rod, check for it to be ovaled.
-Check for wear on the wrist pin itself (if any wear ever shows up).

I haven't pulled my engine apart, too many other projects, but due to the way it went down hill fast, I'm thinking it's more along the lines of a cracked piston (oil consumption and blow-by) out of an engine that really had none of both...

One last point before I disappear, with the piston removed from the engine (still oily) and you can rock the rod from side to side (pin wise), then it's too loose, but only with oil, dry, then there is slack.

Chevy, I have a feeling the Bogger means twisting from side to side in the direction where there is supposed to be no play. I can't put into words what I mean but I think he knows they are full floaters.

Thanks guys for the burnout compliments. :) and the help to figure out the problem. I am going to call up Rex tonight, and maybe get over there on my way home from work.

UPDATE: Haven't had any time to work on the truck, just keeping it clean inside and out for now. Went over to see "Rex" and his diesel sounds SO quiet! Wow, I wish mine was that good sounding. But he heard mine, I revved it and held the engine at different speeds. He said it sounded ok for a 6.5L. the sound hasn't changed any in the 7,000 miles I have had it for. It just turned 169,000. It seems like the sound is coming from the injection pump, on it could be a rocker or lifter, but the valve cover (when touched by stethascope) is relatively quiet when compared to touching the injection pump. I am going to crack open the injectors next weekend, and maybe pull the valve covers. I put some copper RTV on the EGR (blocked by aluminum plate) and it is not leaking anymore. I am just used to quiet (up front) loud back by the tailpipes gassers. I will keep you guys updated on the truck though. I am ordering the 3 gauges: trans, Pyro, EGT, and a transgo with my next paycheck, as well as a homebrewed Turbo Master!! (adjustable from in the cab of couse!)

That's all for now! :)

make sure that that your upper plenium is mating good to the intake and that the doughnut in the middle is sealed good. when you are sure about all of that run your tank low and then poor a bottle of tranny fluid in the tank when you fill up and then run her low again and see if that helps

I will try that chevy man! Anybody else use this trick with the trans fluid?? I am going over to autozone or NAPA to get a new egr gasket. I put some copper rtv around the old gasket, and it is leaking out the front now. I will get a new gasket and try from there. I may have gutted too much when I cleared out the upper plenum, I hope not.

I just filled up yesterday, 2.81 a gallon, figured out to be 18 miles per gallon. That was 529 miles to the tank, driving like a teenager to work everyday (70 miles at least every day), going offroading for about 50 miles with the foot 3/4 to the floor, doing like 45 to 55 miles an hour on old torn up fire trails and along taking it easy along some two tracks at about 15 miles an hour. I had a dirtbike in the back for over half of those 529 miles. The truck is noticably quicker with out that bike in the back.

Right now the truck is running great, just rolled over 170,000 miles, the truck starts up in the morning with a little white smoke, a lotta white this morning ~30 degrees ambient temperature, but smoke went away in about 30 seconds like usual when it is cold in the morning. The knock is still there, and hasn't changed pitch or tone since I bought the truck at 161,000. The engine is strong enough right now, until I get another daily driver, then it will be time for some nice mods.

I am currently trying to make my 1940 buick a reliable car. It is 100% original with the exception of the 1970's bias ply tires, and the removed muffler!! :muahaha: straight eight with a three speed column and straight piped! It is 6 volt and I am debating on whether to convert to 12 volt now, or in the upcoming winter. It runs and drives, but in its present condition I would not drive it 70 miles a day to work. Here are some pics for ya ):h The car is dirty in the pictures, and shines up pretty good after some polish.

Wow! That car is in beautiful shape. Very nice:ro)

Don't try tranny fluid in the fuel tank!

Use 2-stroke engine oil instead, you can go for 1/2 liter on a full tank of fuel, some more or some less doesn't matter.

I will give the two-stroke oil a shot. I just switched oils for my '04 YZ125, now running some nice maxima stuff, so I have a whole quart of that Yamalube 2R. ):h

Thanks for the compliments on the car. I wish I had more time to work on it. :)