Melted oil inlet?

Such problems are usually caused either by a defective thermostat which is stuck closed or defective water pump. Reduced water flow will overheat the head, which will warp it and burn the gasket. The head temperature sensor might be toasted too, not showing head temperature. You should check all those components for proper function, and have the head machined flat if required because it will probably be wrapped.

Bill Spiliotopoulos, '96 XJ, '06 TJ.

You say you 'just got' this vehicle. I'd suspect that the original (previous) owner seriously overheated the engine. (Probably why he sold it...)

Were this my Jeep, I'd flush the coolant, and run it for a while and see if there is additional oil getting into it. You may have simply a case that the previous owner accidently put oil into the cooling system by mistake, but that's hard to say.

Next time you buy a used vehicle, have it inspected by a good mechanic who would have spotted these problems.

I'm a decent mechanic and I did check it out. Nice green coolant when I bought it, nothing suspicious in the overflow tank.

Any chance this is tranny filud in the coolant? Seems strange that there is no coolant in the crankcase.

In article , Noah wrote: # #I'm a decent mechanic and I did check it out. Nice green coolant when I #bought it, nothing suspicious in the overflow tank. # #Any chance this is tranny filud in the coolant? Seems strange that there is #no coolant in the crankcase. #

Is there any mayo on the transmission dipstick?

/herb

None, though since my last post I've checked the level and it seems a bit low - just below the line. I'm pretty anal about oil levels so I don't think it was that low last time I checked it (2 months ago).

I am going to have a local radiator shop take a look and flush the system for me. The guy said he should be able to tell if if the oil is from the transmission or the engine. My fingers are crossed that a new radiator will fix this. He said it's not usual that tranny oil gets into the radiator without coolant getting into the tranny, but he has seen it before. He'll also check the cooling system pressure to make sure that's ok.

Well, you did miss the melted oil filler cap, right?

Automatic? Absolutely possible... You'd probably also have coolant in the transmission as well, check the ATF for contamination.

If it is ATF, then I'd suggest just replacing the existing radiator unit with a seperate transmission cooler.