Loose timing chain?

G.P_XJ

NAXJA Forum User
Location
Centennial, CO
for the past few months my jeep has had a horriable ticking when i start it up in the mornings and when i restart it during the day after its cooled down. Around 2,000 RPM's it sounds like a diesel as well.

From what ive had people tell me it sounds like a loose timing chain, but others have said a bad wrist pin (but it doesnt tick all the time just start up and at 2k)

Does anyone know what else this could be? im really looking for more things that could be wron before i open it up.

Thanks
Garrett
 
carefully rotate the crank pulley by hand back and forth. You can feel slop in the chain. But if she starts quick, idles good, and gets fare MPG. I would look at other problems.
Bad lifter, bent push rod, bad piston rod etc.
 
Most ticking noises I hear from 4.0L's have been stuck lifters, and exhaust leaks. Its pretty obvious when its exhaust or not, so if you think it is internal I would say its posiibly a stuck lifter(s). Quick easy way to try and fix it is right before your oil Change add a up to a quart of atf to your oil and let it run for a few minutes, rev it up a few times and hold it at 2500 for 10 seconds. Then let it idle for ten seconds more and shut off. Change oil and filter. If the noise didnt go away with that, I have heard good things about pouring a Rislone product down the push rods onto the lifters and running the engine. Multiple treatments were necessary in some case's to see good results. Hopefully someone else will chime in on what product it was. goodluck
-----NorCalChris
 
I had an odd noise at idle that resembled a diesel motor until somebody suggested I check the flexplate bolts (I have an auto tranny; flywheel on a manual). I removed the inspection cover and found all four bolts finger tight. Retorqued them and presto, no noise. Worth a check.
 
Last edited:
I had an odd noise at idle that resembled a diesel motor until somebody suggested I check the flexplate bolts (I have an auto tranny; flywheel on a manual). I removed the inspection cover and found all four bolts finger tight. Retorqued them and presto, no noise. Worth a check.


Good idea. All I can add is that I prefer to remove them one at a time, put Loctite on the threads, and then torque them down.
 
This may or may not apply, but from the experience I've had with old timing chains, they tend to get LOUDER as the engine warms up. A Chevy S-10 and one of my old Honda CBR bikes both suffered from loose timing chains, and as they warmed up, the chain metal expanded, causing them to slap the chain covers more and more. If I revved the engines up high enough it would make it stop, but as soon as the engines came back down, they would come back to the diesel noise.

I vote for checking the other things suggested before you tear open the front of the engine.
 
Back
Top