Is this normal?

[DieselAmateur]

Stripped down the original engine that was in the dump truck when I purchased it. Every GM 6.5 I've owned has been a carnage candidate so I never paid much attention to the blocks, they self destructed.

This had insane blow by when I purchased it and I knew the engine was toast, already had a takeout optimizer lined up. Seeing as how none of the mains appear to have cracks and the engine has only 130k on it, I gave the bores a look after teardown. On all cylinders, some more obvious than others, there's a lip near the deck, I'm pointing at it in the picture with the razor knife. On this one you can feel it with your fingertip. Hence the question, is this small yet palpable lip normal, or does it really show how badly worn the cylinder is?



Here's the engine running in the truck several years back, thing had so much blow by it literally blew a hole in the oil fill cap...

I was going to clean up the engine and have a friend measure the bores, but if it's not even worth doing based on the lip and amount of blow by I'll get my $3 in scrap, oversize pistons are too expensive to make this block worth anything

 

[Will L.]

Yeah, that looks like the cylinder wall has something built up on it- not worn down!

It is normal to have the top ring be smaller id than the cylinder because the cylinder got worn away. That looks like gobs of oil burned onto the cylinder wall and stuck somehow. Like maybe the rings were stuck against the piston so fuel burned blowing by the rings and instantly cooked the oil on the walls to it.

It is worse at the top than the bottom?

 

[DieselAmateur]

ah interesting, I didn't think about buildup like that. I'll look at the bottom of the bore tomorrow but I think it's worse at the top. Even with all that blow by you think there could be a slight chance the bores are in stock spec? that would be wild

 

[dbrannon79]

Watching this one my 93 has about this same amount of blow by but doesn't smoke out of the tail pipe like that. did you happen to do a compression test before pulling? do you know about how much oil it was burning though? my 93 drinks about 1/2 a quart over 50-60 miles.

 

[DieselAmateur]

@dbrannon79 I'm pretty sure that the white smoke out the tailpipe was coolant as It didn't hold any in the system when running. When I pulled the heads I was surprised to see the gaskets intact, or at least there wasn't any obvious sign of a blown head gasket. Cracks between at least one set of valves on each head which is seemingly standard on these heads

I didn't do a compression test, the plan was always to pull/ junk the engine. There was so much oil caked on the turbo and intake it's remarkable it didn't run away on its own bad breath. But if the block is good I'd do what I could to get a few bucks for it, anything is more than the price of scrap these days

 

[WarWagon]

This had insane blow by when I purchased it

Set of gapless rings good heads and it could be on it's way patched for cheap. Yes the machine work gets expensive along with new OS parts. Than you look at wear in the rest of the engine.

BTW That's not horrible blowby. I have run worse. It's also a failed oil fill cap regardless of blowby.

Now This is Blowby!

1992 6.5TD Rescue

So I need to be committed now. :wacky: Seriously! :dead: Went and picked this up from north of the middle of nowhere, AZ. 1992 6.5 TD 4x4 3/4t reg cab. INOP and nice and cheap. Work truck with single glass headlights, rubber floor and torn up vinyl seat. Has PW/PL/PS/PB. The PW/PL is...

www.thetruckstop.us

 

[DieselAmateur]

Once again @WarWagon is the carnage king!

Once it warms up (single digits forecast here for the next few nights) I'll do what I can to clean up the block and get it to a friend's shop for measuring. Any potential engine rebuild will be done solely to flip for some money back to fund all my other ongoing projects, diesel sure is an expensive habit...

 

[Big T]

Our ‘94 has similar blowby, but not forceful in that it will not float or dislodge a loosened oil fil cap. I hope to capture the blowby with a Pro Vent catch can that drains into the engine with the Quadstar turbo oil drain block plate.

Other than that, it runs strong. We’ve put 54K miles on it in this condition.