My jeep has a tiny but consistent antifreeze into oil leak. Today I finalllllllly got around to taking the head off. Welll....I coulda just taken the valve cover off and been amazed. There is up to 1/2" of this carbony oily buildup crap. My dodge is spotless and has 150,000 miles more. So what causes this? I've only had this jeep for 10,000 miles and it runs like a top, sommmmehow. Even got 20mpg the other day. It does run hot though.

Did you find the source of the leak? Not sure if your jeep uses a belt or a chain, but Ive seen guides break and the timing chain rub a hole through a coolant passage inside the timing cover in a few different engines. If you do have a timing chain and arent sure of the mileage on it it may be something to check into

Yeah the head gasket was junk. I have a "severe duty" one and ARP head studs for it now. For some reason everything is a dime a dozen for it. Or maybe I'm used to cummins pricing :spend:Head studs for this, $70, for that, $400

That's just cooked oil. Lack of changes and long periods sitting, drying out.

The last head I pulled (84 4.2 in an AMC Eagle) had so much coked oil that I had to chip it away to find all the head bolts. It was stiff turning over and I couldn't get it to fire. Wonder why...

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By the way, that is the same stuff that'll kill your turbo bearings if you shut down hot too often.

I had to chip it away to get to mine as well. Mine wasn't that bad though I mean it runs like a top. How do you get rid of the crap? I can clean the head but the top of the lifters and around there I can just scrape off until its just a light "coating" of the crap.

In our younger dumber years we had a circle track out back and we would buy up cheap cars (by cheap I mean 50 to 100 bucks) knock the glass out of em while they were parked over a tarp and race each other around the track. I found an Eagle for 80 bucks with a bad frame and on the first day on the track knocked the radiator out of it. I ran that thing around the track at least another 20 minutes before the engine flat locked up from overheating. Two hours later I went out and hit the key and it fired up. I ran that thing until it locked up twice more before it grenaded. Those inline engines were pretty dang tough

Excessive head temperature cooking the oil.

I've been researching this for some time now and found many culprits but it seems a lot of the common results boil down to crappy oil that doesn't hold the contaminants so they just "fall" out of the oil and build up on everything. Low detergent oil like super tech crap probably falls under this category. My brother said rosmella is highly detergent and will clean any of the crap I don't get up. I power washed the head and watched chunks of the crap fly off. Then blew it all dry and now letting everything I can get off (rockers, valves, everything) soak in that carb cleaner stuff. I have new gaskets and o rings and stuff for everything so I hope I don't get too many leaks if this rotella crap does clean all the carbon off and expose worn out seals that I didn't change. We'll see. I'm gonna do nothing but let stuff soak all day long.

My cousin has been substituting a quart of trans fluid every 3rd oil change for a long time. He drains approximately one quart, then adds one quart trans fluid and then starts it and runs it at a low to medium idle until the engine gets good and hot then shuts it down drains it again then fills with good oil and new oil filter. He does this with all his vehicles including his farm truck which has been used to haul hay wagons, gravity wagons, seen extended idling, lots of short runs, all the typical farm truck abuse over the last 14 years. We had the valve covers off a year ago to replace a leaky gasket and that engine looked clean as a whistle inside.

I've been researching this for some time now and found many culprits but it seems a lot of the common results boil down to crappy oil that doesn't hold the contaminants so they just "fall" out of the oil and build up on everything. Low detergent oil like super tech crap probably falls under this category. My brother said rosmella is highly detergent and will clean any of the crap I don't get up. I power washed the head and watched chunks of the crap fly off. Then blew it all dry and now letting everything I can get off (rockers, valves, everything) soak in that carb cleaner stuff. I have new gaskets and o rings and stuff for everything so I hope I don't get too many leaks if this rotella crap does clean all the carbon off and expose worn out seals that I didn't change. We'll see. I'm gonna do nothing but let stuff soak all day long.

Don't be knocking the SuperTech oil. I ran that in Mighty Whitey for over 80,000 miles without a complete oil change out.

Don't be knocking the SuperTech oil. I ran that in Mighty Whitey for over 80,000 miles without a complete oil change out.

But you filter it.. I think this is a case of never changing the filter, never changing the oil, etc.

But you filter it.. I think this is a case of never changing the filter, never changing the oil, etc.

And/or the engine never getting up to operating temp to "burn off" any condensed water inside the engine and in the oil. IOW, grocery getter, short trip, urban assault vehicle.

And/or the engine never getting up to operating temp to "burn off" any condensed water inside the engine and in the oil. IOW, grocery getter, short trip, urban assault vehicle.

I got it hot plenty of times Think I just burned off the water and left the sludge. Apparently super tech doesn't have any of the detergents like rotella so once the sludge starts, it isn't going to clean it. Rosmella smells because of those detergents. It's almost done. I have been having to soak every single component in that carb cleaner crap and let it eat all the crap out. I power washed the head and doused it in penetrating oil so it looks brand new at this point. I polished up the valves and valve faces in the head and cleaned all the rockers/springs so they are all brand new looking as well. Gonna throw it all back together today and see what happens.

Some engines didn't have very good oil supply or drainage on the top end and the oil tends to sit and do that when mixing with the condensation sludge.

Some engines didn't have very good oil supply or drainage on the top end and the oil tends to sit and do that when mixing with the condensation sludge.

This^^^^was more of the line I was typing toward ISX.

I had the upper radiator hose off and one end was a little spongy. I looked in it and I guess the inner layer had collapsed so it looked like a bubble of rubber inside it so there was probably very little coolant even going through it. That explains why it runs so hot, among other reasons. I got done but messed up an o ring and its leaking now so I gotta take the fuel rail back off and put an old o ring back in. They weren't bad but I had new ones so figured why not. It did start for a sec before I killed it so at least I know it still runs

So now the question will it overheat again? Will the head gasket leak?

So now the question will it overheat again? Will the head gasket leak?

I got the oring fixed and took it back out and down the road 10 miles and drove into the garage and looked under it for 5 min waiting for a drip, nothing. Looked all over the engine and didn't see anything. I think it's good to go. I'll put it through the paces on the way back home, as usual Sure does idle a lot smoother. I watched a youtube of the same engine with "lifter knock" or something which made it sound like a diesel and mine didn't have that, it just sounded crappy overall. The valves all had buildup on them so I'm not sure how much they were sealing but I polished them up so they are shiny now. Seems to pur now. Hardest thing about it all....the valve cover, of all things. The thermostat housing kinda goes over it a little and the body goes over it a little at the other end so it was just a nightmare to get it in there and not have the gasket get torn up in the process. I wish it was individual like my 12v. Aside from that it was easy. I spent 3 days on it so how hard could it be at that pace

I have seen pics of a 6.7 that looked just like that. Some engines are also known to sludge, I have a corolla that is sludgy. My cummins and most I have seen inside of looked new.

Well it definitely has more power now. Half the trip back is a lot of short but steep hills that it always has issues with. This time it was able to go up them without losing as much speed. On the interstate I went from 70 to 80 going uphill in 5th which it usually couldn't do. I checked the oil this morning after running it a half hour yesterday and driving it 10 miles and the oil was so clean I could barely see it on the dipstick. Usually it is so black you could stand 10ft back and see it no prob We'll see how long it stays that way.