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6.5TD engine expired? Rebuild time?

3500GMC

What T F, over
Messages
5,543
Reaction score
863
Location
Nashport, Ohio
Alrighty gentlemen (and Missy:smile5:)

Bought this truck in signature with known engine problem. I'm not quite the diesel man yet so I need an experienced ear or twenty.

This was a cold start at 80+* air temp. No coolant in oil. Low coolant when I first drug it home- probably a crack or a head gasket. Have not refilled coolant so I do not know if there is an external leak somewhere.

But the racket this thing is making is pretty scary. I see the white smoke and it does have a dead miss. Although today it was pretty smooth. Still smoked though. No road test- don't want to scatter it.

Tell me what you'd do with it. :confused:

Hit the 'HQ' button and crank it up.

http://www.youtube.com/watch?v=k0vPYVbDdyI
 
Sounds like a valve issue.

Possibly a rocker gone bad or a lifter thats collapsed for an exhaust valve

Could possibly be a bad injector too.

Try running it and cracking each injector line one at a time until you see the noise either change or go away.

If the noise stops totally it could be a bad injector.
The video helps but, actually being there would be better ya know.

As far as the coolant loss goes, it could have an external leak OR possibly internal.

If a short run does not see any pressure in the cooling system then it may not be internal.

Run the check with the injectors and see what ya get.

If nothing there, get the top off and remove the lines and the valve covers and have a look.

If nothing there then its gonna have to come out and your gonna have to do an Autopsy on it.

Keep us posted

MGW
 
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Nice lookin truck!! I love the newer rims on them. I watched the vid, but i have no speakers on my 'puter):h. Hope you find the issue, the trucks looks to be in very nice shape, and mechanical pumped, worth the fixing:thumbsup:
 
Thanks for the reply Missy Good Wrench. :thumbsup:

I will crack the injector lines and note any change. I take it that you don't think it's a rod hammering? I don't want to turn EVERYTHING into scrap! :D I guess the fact that the oil pressure is normal could mean the bottom end is OK to check out things further. (40 psi idle +/- a few)

I know what you're saying about the video, not the greatest way to troubleshoot.
 
Nice lookin truck!! I love the newer rims on them. I watched the vid, but i have no speakers on my 'puter):h. Hope you find the issue, the trucks looks to be in very nice shape, and mechanical pumped, worth the fixing:thumbsup:

Well for pity's sake, get yourself some speakers! :D

Thanks for the nice comment on my truck. It has a nice stance. The interior is just about perfect. The previous owner was into stereos, so in the process of replacing every single speaker in it, he broke the dash panel next to the windshield. Have to find me one.
 
First thing i'd do is junk the turbo power cover, it's a good heat retainer. Good looking truck, interior is similar to my '93 3500. Sounds like a steady miss, which goes with the smoke and uneven engine noises. Crack each injector one at a time, see if it goes away with 1 cylinder. Then you know which side to pop off the valvecover & have a look see.
Don
 
DONT JUNK THE COVER!!! If your going to get rid of it, sell it on ebay. Those things go for some decent money. My new engine came with one, i have been trying to find one for a while.
 
The cover has the vents infront of it for a reason, the fan blows air through the underside of the cover to cool the ip. Tell yah the truth i would think it would cool the ip better.
 
DONT JUNK THE COVER!!! If your going to get rid of it, sell it on ebay. Those things go for some decent money. My new engine came with one, i have been trying to find one for a while.

Yea, i'm about to put my original cover on ebay - nice condition if anyone wants it cheap! :eek:) With the '92-93 having the 4911 IP and it's notorious hot start issues, i think it holds the heat in when the engine isn't running thus contributing to the hot start issue. The cover remove or not has been discussed several times, with differing opinions. lol
Don
 
I have my cover on and will only remove it when I have the money to chrome plate everything under the hood. ):h I have heard that chrome plating adds lots of horse power. :rofl:
 
Im sure the cover works to cool things under there, when the truck is running. When not running, yes im sure it holds some type of heat, plastic, kind of an insulator. But i have no pmd there any more, plus it just looks damn cool....
Hmmm, turbo power):h
 
Im sure the cover works to cool things under there, when the truck is running. When not running, yes im sure it holds some type of heat, plastic, kind of an insulator. But i have no pmd there any more, plus it just looks damn cool....
Hmmm, turbo power):h

It does nothing but hide all sorts of things that you'd normally be able to see fail or about to fail or failing ....

I still have mine too, saved it incAse I was going to sell it...

I'll NEVER sell this truck. Drivin it till she dies. HOpefully 10+ more years.
 
Update

Ok, today I cracked open some injector lines and noticed a difference but the knock never changed in intensity. The engine just developed a dead miss as I opened the fitting. That's all. Todays run time (only my 2nd time starting the thing) was a LOT more like the sound of a rod bearing.

Upon firing up the engine today there was a very noticeable SQUEAK until the oil pressure came up, which by the way is getting less and less. :sad:

Still haven't pulled any valve covers. May skip that exercise.
 
It sounds and smokes just like my 98. Mine has low comp. in cyl. #3, low oil pressure when warm and a knock. I suspect a rod bearing and possibly a bent rod in mine. I haven't looked any further.

Leo
 
not so good news

Small update. Pulled the valve covers, everything is clean and tight. In this case it's one of those times you hate to see unbroken parts.

Was at the parts yard today, saw a 6.5TD truck setting there, just arrived... Ooo, there we go. Asked the 'engine dismantler guy' about it.- 'Eh, that ones blow'd up' Sheesh..wouldn't you know it. But it did have the GM-8 turbo.

I dunno what I'm going to do yet. People keep telling me to do a Cummins swap but the complexity and packaging will be a nightmare. If I could address a few key issues with a fresh 6.5, I would probably be happy. Dollar wise, that's a close call between a swap and a fresh and updated 6.5. I think.


One of these days a post mortem will happen. I do believe a rod bearing has given up. Or a wrist pin. Either way it's gotta come out.
 
Yeah, your engine is toast. Sounds like it's not even worth re-building. Tell you what, I'll take it off your hands for you even though it's not worth much.:D

Nice looking friggin truck!! slow down a little on the walk around with the camera next time .....I was working up a nice drool (I might have even been panting a little)

Sounds to me like definite valve issue - might even get lucky like I did. Mine broke one of the little plastic retainer buttons and the rocker arm slid off the valve. Bought a bag of em from the stearlership for around $13.00....<--- That's not a typo it's actually thirteen dollars.....I know, I thought for sure they'd be around $60.00 or more.

The only difference in the sound that yours is making and the sound that mine made was I could barely hear mine as it was on the passenger side...buried under the turbo and heat shield.

If that's the case it's a real easy fix. Use a long 3/8 extension or long screwdriver and press one end to your ear (or the bone right behind the ear - actually works better) and at least probe the two valve covers to make sure it's coming from the driver side. If so, remove the brackets that hold the injector lines in place, remove the lines from the injectors, carefully bend the lines up and out of the way, find something to keep the open ends of the injectors covered - one spec of crud and they're screwed. Remove the valve cover and see whats going on in there.

If you got this truck on the cheap because of what it is doing, I would put my money on you being one happy camper as soon as you get it fixed.

Good Luck


BTW, I noticed in the vid you were checking blow-by - can't really do that on a cold start. Wait until she's good and warmed up(hot actually) and then check it. Don't freak out if you have some.....it's somewhat normal...

Oh, and I would almost bet you can go ahead and remove that "Blown UP" part from your sig......and after you get it running, plan on moving that "daily driver" part next to your 6.5, good grief, what kind of self respecting man (or woman) would drive a camaro when they have a 6.5...unless, of course your that guy that HAS a 6.5 camaro. :)
think positive my friend!
 
Take a deep breath and get the little tired creature out of the truck.

Tag a bag everything like bolts and such as iy comes off. You will thank yourself when it comes time to put it back together.

Get the engine on a stand and do a careful autopsy.

Mark and bag the IP so it will be ready to go when you are. Marking it with a sharp scribe line to the timing housing will assure a trouble free startup.

Get the heads off and then the piston and rod assemblies.

Get the crank out and the cam and lifters.

Now give that beast a dutch scrub with a good dgreaser and HOT water if you can.

Then some good degreasing soap spray. Blow dry.

Now look the lower end over for cracks in the main webs.

Small cracks in the outer bolt holes (center 3 mains) that dont go below the bottom of the hole can be fixed with the Lock and stitch Inserts.

I tossed several very nice blocks that had only some very tiny cracks, before I learned of and purchased the tooling to do the fix.

Once you have your critter spread thin you can locate what is hurting it and get going.

I personally would fix the 6.5

Even if the Block has issues, as long as it can be repaired your good to go.

If the heads are crap, the stuff from clearwater is good (personal experience)
Many many good parts can be found on Ebay at very good prices.

I paid $199 for a complete set (8) Zollner .020 os Pistons for mine

$35 for a set of (8) rings GM factory stuff

$50 for a complete set of Mahle bearings (rods and mains)

I had to resort to the parts house this time for gaskets and lifters.

A great job can be done for a very affordable price.

If you find that your pistons/cyls and such are in good order you can simply clean and resuse them.

The 6.5 blolcks can and will go 200K and still have perfect bores.

Your "NOISE" may not be all that serious.

Take your time and give it a go.


MGW
 
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