Got the piston out. Came right out of the cylinder, no ridge, no problem.

Here are the pics. Any feedback on the condition of this piston or what the pic might tell you would be appreciated.

http://members.bigvalley.net/wuji/jeep/pistons/piston_2a.jpg
http://members.bigvalley.net/wuji/jeep/pistons/piston_2b.jpg
http://members.bigvalley.net/wuji/jeep/pistons/rod_berrings2a.jpg


thanks,

I have 3 more pics. Two of the piston without rings (both sides) and the rings separate.

I left these at a higher resolution to show detail (about 200k each).

http://members.bigvalley.net/wuji/jeep/pistons/piston_2c.jpg
http://members.bigvalley.net/wuji/jeep/pistons/piston_2d.jpg
http://members.bigvalley.net/wuji/jeep/pistons/rings_2a.jpg

3 more close ups of the cylinder wall.

http://members.bigvalley.net/wuji/jeep/pistons/cylinder_2a.jpg
http://members.bigvalley.net/wuji/jeep/pistons/cylinder_2b.jpg
http://members.bigvalley.net/wuji/jeep/pistons/cylinder_2c.jpg

The walls look good. It doesnt look like there is any scoring or anything. It might have been your gasket judging from what the head parts i saw look like. Or it might have been those fickle oil rings. This ones kinda hard. Hmm. When i pulled my head i didnt pull the pistons. I wish i had now, two weeks after i put it all back together the rings on the #2 cylinder went out(sound familiar) The tops of my piston were carboned up but the walls were fine, like your. It might have been the gasket, i didnt see anything wrong with the rings you showed. Good Luck maybe Mike or Sunder or someone knows or has a diffrent angle im not seeing <img src="/forums/images/graemlins/kewl.gif" alt="" />

Well, I don't see a cross-hatch pattern on the cylinder wall so I guess that means it's glazed?

There was no ridge on the cylinder wall so that's good.

The pistons were 40 over bore and the bearings have 010 on them (ten thousands?).

The bearings have copper color showing indicating they are very worn (from what I understand).

It looks like you may have had a stuck oil ring,(oil above and below the wiper) but the larger problem I saw was the rod bearing being totally trashed. With that much copper showing through, it kind of forces you to look at the rest of the main and rod bearings, as well as the condition of the crank. On another topic, do not run straight antifreeze. Antifreeze has very poor heat conductivity properties, and should only be used in the 50% mix method. It lubricates the pump bearings, and keeps things from corroding, but is absolutely horrid at releasing the heat it removes, and pulling the heat from the engine. If it was that great, you would have the manufacturers like Prestone urging you to run it straight. They would make twice as much money then...Be cool...Mike <img src="/forums/images/graemlins/oink.gif" alt="" />

Yes, I understand about the antifreeze. This is interesting as when I bought the jeep the water color looked heavily colored of antifreeze. Didn't know the implications back then and so thought it was good. However, by color doesn't tell me anything. Could have been correct for all I know.

<img src="/forums/images/graemlins/drunk.gif" alt="" />Howdy Mike
Have you ever seen papers on the heat dissapation loss when not using half and half? I have heard this for years and I have wondered how much heat I might be retaining when I fill everything I own with straight antifreeze. Everyone I know never adds water we all add only antifreeze. No complaints from here in Texas from it at all, ever. In all sorts of equiptment, cars, trucks and anything that needs coolant. Is it one of those tiny little losses that lawyers can sue over? If it was truly bad for cooling I am sure we, here in the heat, would have discovered it by now.
I am not trying to argue.. I, too have been aware of the rule for many years. But I have never abided by it. I'd just like to read some real information about it.
<img src="/forums/images/graemlins/drunk.gif" alt="" />Big Jim

Big Jim...I do not have any papers on the antifreeze subject, but in this climate I do have a lot of experience with antifreeze over use. In the summertime, we find that vehicles run about 15 to 25 degrees warmer with a heavy antifreeze mix, and on a vehicle with a marginal cooling system, it is often the difference in sitting at the side of the road during rush hour, or sitting with the family. The over use of antifreeze in winter shows symptoms much easier. If a vehicle has too much antifreeze below 20 degrees, and heat is needed, you seem to get more warmth by opening the window, than out of the heater. Once the temp reaches around zero, there is a real risk of doing damage to the block, especially along castings, like between freeze plugs. From what I am told, the extreme cold, combined with a coolant that is not pulling out enough therms, causes the cast block to go through some changes it was not really designed to do. This causes stress to the castings, and will crack the block. We use antifreeze at work for hydraulic fluid on things that come in contact with molten steel, because it doesn't absorb much heat, and due to the fact it doesn't burn as easily as some of the more mineral based fluids. I was just putting out info from what I have learned in school, and from what I have experienced in the field. If straight antifreeze works for you, then more power to you. Looking at the engine though, it appears that the antifreeze that was in the cooling system may have entered the oil galley, and caused the bearings to get wiped out. If a rebuild is going to take place, it should include all the bearings, including the cam bearings, if oil pressure isn't to become an issue in the future...Be cool...Mike <img src="/forums/images/graemlins/oink.gif" alt="" />

<img src="/forums/images/graemlins/drunk.gif" alt="" />Howdy Mike
I kinda sorta agree about the engine and the bearings. It is indeed strange that the bearing is in such bad shape and the cylinder is not! The ring groove that should be there is not.
On the antifreeze question. That would be a good thing for me to do this summer... I could extract the engine intake hose and install a temp sending unit in it! That would bive me 2 readings in the dash. With this I could then use all antifreeze and then slowly add water till I got to 100% water. Hmmm With this well I have here I could even go so far as to use extreemly hard and extreemly soft water.. Might be something to occupy my time. Maybe Leve will come around with some of his 1, 2, 3's and have an opinion!
Big Jim

edit! What I have found is that no matter how hot it gets down here the engine temp reads the same year around... So maybe what is happening is that the thermostat is opening wider to allow more fluid to pass. I am thinking from your post that perhaps the fluid temp is entering the engine hotter than if it was water only. hmmm This should be good for the engine shouldn't it? not having a colder fluid entering? Seems that in zero temp (shudder) one would have zero fluid entering no matter what fluid was in there... Just thinking out loud.
<img src="/forums/images/graemlins/drunk.gif" alt="" />Big Jim