89 renix 4.0 278k miles

for the last month it developed a valvetrain tick that comes and goes as i drive, deff not an exhaust leak, i opened oil filler cap and its deff coming from the valtrain, near the distributor

the car still drives normal, no power loss

i am thinking sticking lifter?

what would be a good test to start with? should i pop the valve cover off and let it idle to see?

 

Lifters r down low, at the base/side of the block. If u suspect the valve train (noise up high), remove the valve cover and check for worn rocker arms, correct rocker bridge torque and pull each push rod to see if it's clear/not plugged/straight. Each rocker arm should have a good pool of oil in it's valleys, if not, possible plugged push rod.

 

ok am gonna try that, another question

can i remove the valve cover and let the car idle to? or will i get a buncha oil splashing everywhere??

also is it OK to drive around town with it making this noise?

 

Check your distributor shaft for side to side play...could be just the bearing on the distributor. The sound will echo all through the block.

 

how do i do that? pull the distrubutor out?

 

Start it up with the valve cover on and let it idle/warm up a bit, then remove the valve cover. If each of the rocker arms have oil pooled in their valleys, then oil is flowing thru the push rods. Any dry rockers, suspect the push rod is plugged. Kinda hard to not loose some oil when the motor is running and the valve cover is off. Without knowing how bad the noise is or what it is, it's kinda hard to know what driving will do. The XJ 4.0L is a noisy motor.

 

X2 on it being a noisy motor, sorta like the old GM 4-cyl "Iron Duke". It started rattling at 75 K, and rattled for another 100 K...

 

Remove the distributor cap and rotor, then with your hand and fingers grasp the top of the shaft and see if you can move it side to side. I understand that there should be no play at all. Look at the inside of the cap for unusual markings or uneven wear from contact with the rotor.

 

+1 to this. I had a noise I thought for sure was coming from the valves, turned out the bearings in the dist were toast and the rotor was eating it's way through the points on the cap. I figured it out by placing one end of a large screwdriver on the dist cap with the engine running and the other end to my ear. The noise was much louder than if I put it against the valve cover. It's a 30 second check before you start tearing things apart.