real new to diesels motor question

[Old Rusty m1008]

1986 CUCV
My 6.2 has a problem that im hoping is an easy fix. I start it cold and for a while it runs with an exhaust valve that i think is stuck open as exhaust backs up through the intake and you see puffs of smoke coming out the air cleaner.During this it misses and doesnt want to rev up past 2000 RPM. Usually after it warms up this goes away and it runs good..
The truck has just over 30K on it
Is there something i can run through the motor in the oil or something that is a quick easy fix or am i looking at a major job rebuilding heads or the motor?

 

[rickf]

Although I am not a big fan of additives I have seen Marvel Mystery Oil loosen up stuck lifters. This may not be your problem but it can't hurt to throw some in the oil and see what happens. Change the oil and filter at the same time, could be dirty oil.

Rick

 

[Old Rusty m1008]

Ill give it a shot thanks!

 

[iacucv]

Not sure on diesel but I imagine it would be the same, I've been told to run a quart or two of ATF in the oil. The high detergent ATF is supposed to clean things up nicely. Ran it in my Durango and had no ill effects. This is on a every so often, rare kind of basis, for only a couple thousand miles or so.

 

[rattlecan6104]

From what I have seen as far as running "additives" through oil many people I have talked to have sworn by sea foam. I have tried it in my deuce and I could physically hear the engine start to run smother over the course of half an hour sitting and running. Im pretty sure at this point it isnt helping you much hearing 3 different "additive" answers, but at least its some direction for you to start in. good luck.

 

[Tlauden]

I have also heard of seafoam working wonders although i myself have never used it. Best of luck to ya

 

[swbradley1]

I used SeaFoam in my Dodge Hemi crankcase and it seems to have helped a ticking lifter.

 

[Old Rusty m1008]

im gonna try some of that.. Im out in NJ so now that we survived sandy, we are expecting a nor easter which should cause more power outages and flooding.. Assuming that dont hurt me ill fool with this truck the end of the week
Thanks for all the replies thus far and please if ya have any other ideas please keep em coming!

 

[Skinny]

Nor Easter...did I miss something???

 

[PsycoBob]

Kreen from Kano Labs works wonders- a quart in the oil & a hundred miles of driving will remove disturbing amounts of sludge & free stuck lifters & rings. Change your oil withing a few hundred miles of adding it- the product boils off pretty quick, but the nasty junk it just removed will still be in the oil.

When I used it on my deuce, the oil thickened considerably & it left everything I could see on the valvetrain & filter bases factory-clean.

 

[85CUCVtom]

I used Seafoam in my 4.0L jeep to free up a lifter. Follow the instructions and give it a try.

 

[Keith_J]

Roller tappets, really high tech in such an ancient engine. With this little tidbit of information, you can feel a bit more confident to use strange brews in removing varnish, debris etc from the engine.

If this is a vehicle that may have seen prior shade tree mechanic service, you may have a head shaved to correct flatness.

 

[cucv1833]

I ran Seafoam through my 6.2 last oil change. I put the recommended dosage in and let it run for 30 min in the drive way and then changed the oil whie it was still warm. Not really sure of the results.

 

[Old Rusty m1008]

im gonna try some kind of detergent in the oil and a complete change once i get the SF 97 and can drive it Im going to bring it to my buddys shop to do t he oil change anyway im too old to be crawling on the ground in winter lol when i can go there and borrow a lift lol

 

[MarcusOReallyus]

im too old to be crawling on the ground in winter lol when i can go there and borrow a lift lol

Hey, 18 is too old to be crawling on the ground in winter when you can borrow a lift!

 

[Keith_J]

Yeah, that is a perk to helping out a fellow Steel Soldier member. He has a shop with smooth floor and air conditioning. No lift but a smooth floor beats gravel.

I've used cyclohexanone, an industrial ketone (think acetone family, like MEK only less vapor issue) to free stuck lifters. Just a few ounces per quart in dirty oil. Once the problem goes away, change the oil.

With roller lifters, you should be fine.

 

[Gov Junk]

I was working on a 1970 Olds 350 engine last week doing the exact same thing as your engine. The exception was that it did not clear up after warm up. Bought a can of SeaFoam and was going to pour it in the fuel tank. Got to reading on the back of the can and it suggested to warm the engine and remove a vacuum line from the intake with engine running and let it suck 8oz. of product into manifold and turn off engine. Did as directed and within 3 miles of driving it had cleared up and ran flawlessly. I don't know what is in SeaFoam but it was like a miracle in a can. Worked for me!!

 

[rickf]

They are all the same, It is a solvent. Do not use the vacuum line on your diesel or you will wipe out the vacuum pump, diesel engines do not produce vacuum. All of these suggestions are going on the assumption that you have a sticky lifter. Try this first but if it does not work do not be surprised. It could be many different things, bent pushrods, bad adjustment. These lifters go bad a lot. I have had several bad lifters. This is just a cheap first step to try.

Rick