My yj recently overheated. I replaced the radiator, which solved my cooling prob, but then it had low oil pressure.

Now, last week, i got a dead cylinder, and zero oil pressure. i replaced a plug and wire, nothing. so i took the valve cover off and discovered a collapsed lifter and blown headgasket. I pulled the head, and replaced all lifters, headgasket, and just cause i had it out, the thermostat. I did 2 oil changes and 2 coolant flushes.


Now, when cold, i have about 30lbs of oil pressure. But when it warms up, and i am on the gas, I have about 20lbs. at idle it goes down to zero.

I'm thinking its the oil pressure sending unit or oil pump, but i dunno a whole lot:confused:

My yj recently overheated. I replaced the radiator, which solved my cooling prob, but then it had low oil pressure.

Now, last week, i got a dead cylinder, and zero oil pressure. i replaced a plug and wire, nothing. so i took the valve cover off and discovered a collapsed lifter and blown headgasket. I pulled the head, and replaced all lifters, headgasket, and just cause i had it out, the thermostat. I did 2 oil changes and 2 coolant flushes.


Now, when cold, i have about 30lbs of oil pressure. But when it warms up, and i am on the gas, I have about 20lbs. at idle it goes down to zero.

I'm thinking its the oil pressure sending unit or oil pump, but i dunno a whole lot:confused:

My oil pump pick up tube fell off mine and acted the same way.
Not saying that is your problem but it is a Jeep :)

any other comments?

new symptom on the yj:

after warm, I pulled the oil fill cap and some whisps of smoke came out. It looked like it was coming from the openings that the connecting rods run through.

anyone? this is confusing to me:confused:

hello?

new symptom on the yj:

after warm, I pulled the oil fill cap and some whisps of smoke came out. It looked like it was coming from the openings that the connecting rods run through.

Thats normal - if its just a little and not like a salmon smoker...

I'm tellin ya....Check the pick up tube man! :D

ate up the rod bearings maybe, how long have you let it idle at zero... mine was doing that and after about 10 minutes of idleing at 0 it finally started to faintly knock. (it was coming out anyway) I would verify the OP with a $10 mechanical guage from NAPA and if it in in fact 0 pull the pan and swap the rod bearings if they look worn. Maybe run a compression check too. If it still does it I would look at the cam bearings, but at that point you might as well pull it

sorry, I pulled the pan and checked the pickup already, its fine. I haven't let it idle at zero very long. compression is good, main bearings look fine. I think its been narrowed down to the cam bearings.

Have you replaced the oil pump?