bad_idea

LOTS! I just bought a 90 2.5L 5speed 2WD SWB Comanche. Paid $400 for it and hauled it home on the trailer. PO parked it 2 years ago when the radiator failed, overheated, and he had it towed to the house. Been sitting since. I threw a radiator in it and jumped it. Started right up and ran ok-ish. The rubber 90 on the front of the valve cover is cracked and spewing smoke at idle. I gave it a few minutes to clear up, but it never did. I drove it down the street and back. Parked it in the driveway and smoke was billowing out from under the hood. Popped the hood and there is oil all over the top of the engine. Looks like it was spewing out of the rubber 90 on the front of the valve cover.

I assume it's excessive blow-by from worn rings. Are there any other options? I would love for it to be something cheap and easy. I'd like to get some miles out of this motor. I didn't check the CCV line at the back of the valve cover. It may be plugged, but I can't imagine that would account for this much oil/smoke. Could it?

I am just scratching the surface on this truck. I will dive into it as time permits. Any pointers? I would LOVE if it could be something simple. Not rebuilding this engine, will yank it and do a motor swap. Hoping to put that off a year or two though.

tjwalker

1. Replace valve cover.

2. Replace CCV hoses/grommets. All of it. If memory serves me, you can get the entire shooting match for around $50. Napa, online, other sources.

3. Perform a simple compression test on all cylinders. The spec is 120-150 psi with no more than a 30 psi variation between cylinders. This test is a very good "snapshot in time" on the internal condition of the engine.

bad_idea

How can the valve cover cause smoke to billow from the broken fitting going to the air filter housing?

I replaced the entire CCV on my 90 XJ for maybe $15 on Rock Auto. I'll put a new one on and see if that makes a difference. Will also have to replace the rubber 90 going to the air filter hosing. I am not where to buy that though. Have had trouble finding that in the past.

dave1123

That's compression gases blowing past the piston rings and carrying oil with it.

bad_idea

Yeah, I figured as much. I was hoping someone would tell me it's no big deal and a $5 fix. I guess the next question is can I get some more miles out of this engine? I'm thinking verify the CCV line is not plugged, replace the breather pipe assembly on the front of the valve cover to the air filter housing, and install a catch can between the valve cover and air filter housing. Any other tricks to reduce the smoking? Thicker oil? Oil additives? This is an extra vehicle for putting around town. I would like to get some life out of it if I can. Not relying on this truck to get me to work. Thanks all.

cruiser54

Make sure the CCV system is good and do a dry/wet compression test.