4x4cherokeexj

My engine at idle taps. My grandpa says its the rockers. his cousin says put some 50w oil in there and that will fix it. Its not a rod knock its just a small tap tap tap tap tap tap tap tap tap tap. What do you guys think it is ? im idling fine temp is fine everything is fine.

outkast

I think its a 4.0L, seriously I don't think I have ever heard a Jeep engine that didn't have a little tap to it. It probably is rockers or wrist pins or maybe even piston slap.

4x4cherokeexj

4.0High output. I would like to try to get rid of the tap if i could so it doesnt make the buyer cautious.

notop46

Most likely valve lifter sticking. If so, 50W oil will not help. Pull the valve cover, check all the valve adjustments. If everything is in order, start engine and listen to the rocker arms with a stethascope (use a small plastic tube with one end up to your ear and the other near the rocker arm). If you find a rocker that is tapping louder than the others, remove it and the pushrod and spray WD-40 or Marvel Myster Oil down on the lifter. I pumped mine a few times with a long steel rod with rounded ends to work in the lube. (Dont drop rod in engine) Reassemble rocker and adjust valve. Restart and check for tapping. Repeat as nesessary. Install valve cover, check oil level, and clean up any oil spills before driving.

Keep Cherokee and sell grandpa and his cousin :-)

TheJerm

There are no valve adjustments...

X2 on a sticky valve

4x4cherokeexj

Lol i dont want to keep this cherokee nothing but problems for me so far. The other cherokee (94) is perfect besides a new head gasket. My jeep was a lot of work so far. would rather not mess with it anymore then already have.

G O B

Try a quart of Marvel Mystery oil in the engine oil and another in the gas tank. If it is a lifter gummed and sticking this will free it in 200 miles or so.

lolz_jeep

valves or ur gettin a rod knock. but my jeep kinda ticks i guess at idle

outkast

I would still put money on a piston skirt tapping the cylinder wall or a wrist pin. If the knock goes away off idle or under load I would bet a a wrist pin. If it gets worse off idle but not under load I would say rod bearings.