What caused this cylinder wall pattern? (1 Viewer)

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Lafayette, CO
So, I've got her all torn down now and I'm going back through the pictures and I found these. What caused these weird patterns on the cylinder wall that appear to be something to do with the oil rings, but they aren't all at the same height, and are rotated as well? I just don't get the "ghosting" at all the other levels.

This engine had a oil pressure loss due to the crank bolt being loose, and the #5 rod bearing s*** the bed. The piston was just starting to hit the head, barely. I think I got to it in time. It wasn't my truck until the engine was known gone, so I know no history.

On teardown, I found that the compression ring gaps were nearly lined up on most of the cylinders. What could cause this? Do the rings walk around that much? Was there some disgruntled employee at the Mr T factory that day? I'm 99% certain that this engine has never been torn down, at least to the level I have it now.

Back to the frosted pattern on the walls, do you think water sat in the cylinders for a while and ever so slightly corroded the pattern into the walls?

I don't know. It won't be a problem in a week or so, but I thought it was interesting at least.

Thanks,
Jim
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was the car sitting for a long time? oh and check the condition of the oil squirters under the pistons
 
X2 looks like it was sitting for a long time with water/coolant inside or lack of oil before it was parked. Was the head gasket blown?
 
I would guess it sat for a while. Even without water in it, you could get marks like that.
 
X4 or whatever on that being where the piston was parked at while water/coolant was in there. Cast iron doesnt take long to rust up.

I got mine with a nasty knock also. So I would guess mine is in similiar condition. Although mine is not burning coolant that I know of. It runs like a top. With great power and mileage(for a 80) So I believe my rod bearing is toast.
 
Yup, just looks like it sat for a while and the rings left marks on the cylinder walls. Can you catch any of those marks with your finger nail?
 
This engine was starved for oil due to the loose crank bolt. I don't think the HG was blown but there may have been a little seepage. I can't catch the frosted patterns but the compression rings at TDC are wore in a few thou. I'm sure it sat for months at a time and was only started and run for a few seconds several times. It sounded real bad!
 
So you asked us and answered your own question???
 
skintunes said:
So you asked us and answered your own question???

I wasn't sure what caused it. I thought maybe someone might have a different or better answer.
When I first saw it I was wondering if it could have been gases causing the oil ring to bounce, or some sort of preignition, but I couldn't explain the multiple ghosting patterns further down the walls. I had no reason to suspect the HG, so maybe it was condensation.
Sorry if I offended you with my question. It was just something I hadn't seen before.
Thanks to everyone else for the comments.
 
blkprj80: do you plan on doing a complete rebuild?
 
At 150k, it's easy to see the factory cylinder wall finish, which is a cross hatched pattern similar to what you are calling "feathering or frosted" pattern. However, in the picture it looks like someone has honed the cylinders as the pattern seems way more pronounced than the FZJs I've seen. If so, then the engine's been apart and that would explain the mistake of having all the ring gaps in the same spot, AND the incorrectly torqued crank pulley. And probably some other stuff there. Looks like the engine got a rebuild and not a good one.

DougM
 
Original old style head gasket. Not a rebuild. Also this engines rings were also getting a bunch of carbon behind the rings and holding them out and not allowing them to return in to the land area. Thus acclerating wear on the cylinder wall. This can be due to a few factors. Not consistant oil changes, poor fuel quality, short travel distances between on and off with out full warm ups. I also agree that the pistons have been sitting in a spot with some fluid in them to transfer the patterns of the oil control rings onto the cylinder wall.
Nasty engine
I will call today Jim to set a time to look at this for you.
 
Thanks for the call Robbie. :)
Kernal, yes, this is getting a complete rebuild. I hope to do as much as I can myself, with Robbie's expert help when needed. I want to learn as much about this as I can. I have plenty of time, it's my project and it has a semi-permanent place in my garage right now.
IDDoug, I know someone replaced the PS pump (and they did a s***ty job), but I don't know if someone did the timing chain or what. Maybe they started to tear it down and bailed? I'm just hoping the components are re-usable for the most part.
 
wow so a loose crank pulley bolt had oil coming out the front through the crankshaft?

No, the loose crank pulley bolt let the gear on the front of the crank slip. This gear drives the oil pump and the power steering pump. There was probably always plenty of oil in the pan, the pump just quit moving it when the gear was slipping. The #5 rod bearing let loose first. The others were not good, but not spun yet. #5 was paper thin. #5 was a long ways from the oil pump. It saw the least oil when the oil pump slowed or stopped. The gear that was on the crank shows signs of slipping, but it doesn't appear to be FUBAR. I'll let Robbie make that call though.

Here's what the gear and crank mating area look like. Shiny, but not galled. Guess you'd call it "polished" if you were planning (hoping) to re-use it.

My neighbor thinks this is a design flaw, but I keep telling him that if it had been tightened correctly it wouldn't have failed. Granted, it's not idiot proof, and I must admit 300+ ft-lb is freakin' tight! Not that i would know. My crank bolt came off with a 12" long ratchet handle. Somebody before me forgot to tighten it, or they didn't get it as tight as it should have been.
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Good eye, Robbie - orig style HG, eh? Was looking at it in his pics before posting and finally decided I could not tell for sure. Always good to get the expert opine.

Yes, the crank bolt is worth either renting a torque wrench or buying one. Hope the engine is save-able as you're in good hands with Robbie involved.

DougM
 
Doug, You can see the metal imprint on the surface of the block. Metal was used on the under side on the first generation (original) Head gasket. On the later versions the metal is on the top next to the head, and used for the circle on the fire ring. And the metal extends to all the bolt holes to stablize the fire ring so it will not deform like in the first generation HG.
 
I can add some more info to one of those questions....the one about the rings moving around.

"On teardown, I found that the compression ring gaps were nearly lined up on most of the cylinders. What could cause this? Do the rings walk around that much?"

When I had a mechanical shop in town I got curious about that very thing so I took to noting where the gaps were when I rebuilt an engine. Over the years, I got to see some in a subsequent teardown.

THE ANSWER IS:: (big drum roll)

Well, H8 to let you down, but unfortunately the answer is like many mechanical things. That is, most of them move around ....but not all of them do. No, I don't know why. I never saw enough to answer that. But I did notice that the ones that move did so at different rates. I would set new rings up with the gaps 180 degrees out, but sometimes found them lined up later.

Oh, on the odd wear pattern on your cylinders.....the ghosting you posted. I'm not sure, but I think I've seen that before. But it was in the bore area where the oil control ring traveled and I only saw it in a few cases on pistons using heavy two piece oil rings - by which I mean the kind of dual scraper oil control ring that is horizontally slotted and has a corrugated ring expander behind the scraper part. But the wear on your bore looks more like it is in the area of the compression ring(s). So the reason may be entirely different.
rScotty
 

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