Thanks for the feedback Steve. I think I made it sound easy when I was speaking of the piston coming right out. I pushed it up from the bottom with a wood hammer handle. It got so far then had some tension. I then when to the top and saw the first two rings were above the top so I then pulled from the top. This is where it was more difficult to come out. Like the oil ring(s) were causing the tension. Anyway, it finally came out and that's where we are. The two compression rings did expand and have outward tension.
Steve hit the nail on the head here. If this engine was recently gone through, then there were things done improperly. It looks like it has 100k miles on it. First off, the crosshatch should be visible in the cylinders for tens of thousands of miles after a bore/hone job, unless the engine was honed for the racing type rings, but yours shouldn't have been. If it was, this was the wrong thing to do. The rings will never seat properly and will cause cylinder gases and heat to pass by the rings and heat the area around the oil ring. This could be why you had so much crud in the oil rings. The oil gets hot enough to "char" for lack of a better word. Second, based on the condition of the bearings, the rod ends are out of round, or the bearings were reused old ones. This needs to be addressed.
You have to decide at this point if you want to patch this engine up or totally go through it, but then the previous overbore becomes an issue. I'm not sure if the 258 is acceptable with a .060 overbore or not. From what I've read, most of the 4.0's are ok to go .060 over, but each engine has its own limitations based on casting thickness.
Anyway, if you want to patch it up, have the following done:
Have someone check the piston to bore clearance. If it is within spec, then decide which rings you are going to use (I'd use the Hastings or some other stock replacement moly rings).
Have the rod bores checked out. If they are out of round, then have them resized back to spec. This is also a good time to replace the rod bolts with a good set of ARP bolts. Rod bolts fatigue and become brittle over time.
It's a must to replace all the rod bearings based on the looks of the one in your pictures. I would also check the mains as well and replace them if they don't look good.
If all of the expense of this doesn't deter you, then clean everything up until it is spotless. You'll need a few things to properly clean and assemble your parts afterwards. If you go that way, I'll post the info here.
If the engine had less of a bore and if I could pull the engine where I am (appt complex) I would consider it. I think right now, based on the possiblity of deeper problems, I'm going to look for a replacement engine. I could go through the motions and invest in all these parts but because I can't have an expert look at the block the work has a possiblity of being for nothing as a greater problem that I can't see might exist and come back to haunt me. I'm going to take the $$$ and find something else.
This is what I have ready for whatever short block I can get:
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A freshly machined 4.0L head with a new 4.0L exhaust manifold.
I don't think this old block will be able to handle it.
Just be real careful with the broken ring like you said. A small gouge in the ring land will really mess things up. I like to keep a small bucket of my old carb cleaner around (methylene chloride). After it's service life is over for cleaning carbs, it is the best degreaser/decarbonizer out there. I'm not sure if you can get it in Kalifornia or not, but it is called Mac's carburetor cleaner and is available at NAPA. Just wear good industrial nitrile gloves and use it in a well ventilated area. You will have all 6 pistons cleaned in an hour or less without scraping or scrubbing one bit.
Why use gloves? Are some of these chems dangorus to the skin?
When I was at the performance shop I notice the mechanic had latex gloves on (I think they were latex). Was this to keep his hands clean or prevent eventual chemical injury or both.
I've been spraying engine cleaner on my engine parts and wiping them off with an old towel. I touch grease and oil all the time when changing out parts.
Both - Oil, petrol, brake fluid etc are all nasty to the skin. The mechanic has to deal with this every day, so its worth him taking precautions. You and I probably only wrench at the weekend for a few hours max !
Well, look at how effective those "patches" are for smoking and the like. I'd say that anything you touch will get in your system to do some sort of damage.
Did some work in a bingo hall and was touching the dust on the tops of their tv's...and well...I sure got a good buzz real quick.
I'm pretty sure they don't suggest ingesting any of those items so I'm sure getting them on your skin has some longterm issues. I'm sure they'll kill off some brain cells.
But...like natural selection, I'm sure they only go after the weaker cells. So...in the long run you'd actually end up healthier and smarter.... (I stole that from Cliff Claven form Cheers...haha)
When I pulled my 258 apart I soaked each piston in a coffee can of WD40, figuring that the solvent would remove some of the crud and varnish and that the oil in it couldn't hurt the metal. FWIW, it did seem to make it easier to scrape the carbon out of the ring grooves -- but that could just be voodoo on my part.
Gasoline has too many additives these days for me to want to wear it for very long.
Some can go right thru the skin and cause severe nerve damage or worse. e.g. Carbon Disulfide which is an excellent way to clean carbon but smells like stale beerfarts and goes thru the skin so easily it is also used in alternative medicine.
Solvents go thru rubber gloves about as well as skin. e.g. methylene chloride or carbon disulf. Worse, some of them can carry other molecules thru the skin with it.
If you do this regularly, you are putting your skin at risk of cancer and/or nerve damage.
I'll bet you enjoyed the mental image of me hunkered over a coffee can, emptying spray cans *psssssssssssssst* one at a time, but I'm glad to say that it wasn't so. A non-areosol gallon can of WD40 at the local AutoZone runs about $18US, and it will be a lifetime supply for me.
WD-40 Lubricant, One Gallon Can: Safetysupplies.com, Inc.
I'm probably completely wrong-headed on this but for some irrational reason I'm willing to soak my hands in WD40 but not in other solvents, probably because I _know_ the others are bad for me and I don't know that WD is too.
Besides, fire is not our friend and it damned sure isn't tame. I've seen fire, I've seen skin burns and I've seen people get stupid with gasoline. I try to stay away from it as much as I can to prevent my involvement with any of the three.
Ok Bill, just got back from a bush run and read the thread and looked at all the photos....
Here is my $0.02 for what it is worth. ;-)
Man, that set of photos sure looks like a classic case of gas wash killing one cylinder dead. Big Time!
The gas washing all the carbon out and cleaning the rings so oil comes up and gets flash burnt when you change plugs and it fires for a while. While it's firing that flaky varnish looking crap builds up from the burning slurry.
Then the build up finally kills the spark.
No spark, so on a normal compression or firing stroke, the cylinder is in a vacuum mode and the piston needs to be pulled down against that vacuum rather than the spark firing the piston down.
The vacuum must be released or the engine will up and stop.
'Some' oil will be then sucked up past the rings and sucked down past the valve guide seals when this is happening, whichever is looser. Hmm, valve guide seals maybe eh? So when it shuts off, the vacuum sucks oil down from the top, then it mixed with some gas to be thin and spread, spreads across to the spark plug threads. Hmmm....???
Now the poor old crank which sounds like a 10/10 is not used to or designed to have any piston under suction, the piston is under spark or intake or exhaust, no vacuum motion involved.
Check on top of the oil filter on the block boss for a letter. If M and P are there, it is a factory 10/10 crank which is just 10 thousands under. You can go to 30 or 40 if desperate, 20 is fine. B means factory 10 thou over piston. C means cam 10 over.
This vacuum in the cylinder because of no spark means the crank slams down on the bearing and wears the crap out of the center of the bottom bearing on the cap side. The cap side isn't designed for pulling, just being in neutral to the push from the piston rod on spark or sucking from the carb/ TB or blowing out the exhaust which is zip for pressure point wear like is showing.
If the engine is newly rebuilt like advertised, the vacuum on the cylinder would be nasty. The compression was way up there, so the vacuum 'was' up there too...
Bingo, burned out rod cap bearing and likely both main bearings on each side.
I also would be worried the cap and rod and the crank journal could have been pounded out of round from this.
I seem to remember a complaint about a timing ping or knock at idle??? Hmm vacuum on a piston starting the crank slapping on the bearing makes a neat knock. The bearing can wear away and the knock can lessen or get worse. The first while with the dead cylinder causes the big damage.
Then the cylinder is polished up sweet! Well, carbon under heat with gas as a solvent has been sliding around those rings for a while, damn near a diamond polish, eh?
No lip, so it 'sure' isn't burnt worn, it is gas washed or gas polished, that 'is' what they look like. I come from the carb days and have seen engines that look like that from short term gas wash. Normally on all or a half bank though, not like injection that just nails one.
You need to open some other rod and main bearing caps and post the photos.
If those are not burnt out or worn through then the gas wash theory holds, if everything is fried, then it was a dud engine someone sold you or the other person under the 'used' engine tag.
If just gas washed, a hone on the cylinder and some new stock 10 under bearings should do the trick. You have to buy the whole bearing set and it is open, so just swap them all.
While it is out, that one piston rod should have the cap torqued on properly and be mic'ed out for round. Most engine shops around here charge $20.00 to over grind a rod end or make it true round again and have a bearing to fit.
Ok, that was long winded.... Whew... ;-)
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Long winded but good. No doubt a bit of experience pushing those words out. I'm gonna have to get my chilton/service book so that I can have a picture and I'll read this again!! haha that way I MIGHT have a clue what you just said!
Just got the following from a friend of mine. Dunno the veracity of the story but it's from the internet so it MUST be true :-) Interesting claim that there is nothing in the stuff that would hurt you.
It's good stuff for sure...and I do like the scent. But I'd say it isn't good for you. I used an old styrofoam cooler to put some parts in after I had sprayed them with WD-40. well, the bottom of the cooler got dissolved.
And I wonder of the use of this stuff for arthritis....kills nerve endings maybe??
And the fishing one is that it gets rid of your smell off the lure...doesn't attract them, unless that cool rainbow streak coming from the lure floating in the water does anything.
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