Noisy lifters & engine oil leak on 4.2L

cdlongjr · 10-29-2009, 03:53 AM

My lifters seem to be very noisy. Is there an adjustment, engine flush or oil additive that would quiet them down? I've already added Lucus to the engine oil. Next oil change I'm going to a straight 40W oil. I also have oil on the outside of the starter. Any sealers out there that might help? I've already replaced the rocker cover gasket & can't see any leaks from it.

**JeepOrvis97** · 10-30-2009, 02:46 PM

My 4.2L is leaking oil out of the PCV breather, I think the seal is crap. Also, exhaust manifold leaks can sound like ticking, might want to look into that too.

cdlongjr · 10-31-2009, 03:50 AM

Beather cap is dry. Exhaust has been replaced. No leaks. This is a metallic sound coming from the top of the head. I haven't been into the engine other than to replace the rocker cover gasket.

**gabec05** · 11-08-2009, 10:24 PM

Rocker pivots were made of aluminum. Some times the aluminum would wear more than the lifter could adjust for. Pull the valve cover start the engine.If this is the problem with engine idleing the noise will be right infront of you. Turn off engine wiggle rockers, all rockers should be tight. If any are loose remove that pair and inspect inside of rocker and underside of pivot. If they are worn and scored replace all rockers and stools. These engines did not have adjustable rockers

**JeepRestoration** · 11-19-2009, 10:00 AM

It sounds like you have a high mileage engine. Remove the oil filler cap and take a look at the tops of the tappets and valve train (you may have to remove the valve cover). Is everything getting lots of oil?

High mileage engines often lose oil pressure with bearing wear and or sludge deposits on the oil sump screen. The first signs are a loss of / or reduction of oil flow to the upper valve train which results in valve train noise. If this is the case, driving the vehicle will result in serious damage.

The oil leak you mention could be a rear main bearing seal leak which is common with high mileage engines. OR it could be a leak at the rear of the valve cover running down near the starter or it could be a leaking oil sender unit which is just above the starter on the L6 engine. Check all these things. In fact it may be useful to degrease the engine and then watch for signs of fresh oil.

While it hard to make a call with limited info, you may be in the market for a new engine soon.

Good luck.

carnuck · 11-20-2009, 01:21 AM

I replaced mine with a 4.0L

93yupj · 12-05-2009, 12:01 PM

Im currently in the 4.0 swap process myself way better bang for the buck.