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knock, knock!

slowrider

NAXJA Forum User
More help! My 40k mile rebuilt 89 mj 4X4 4.0 has developed a knock that is only present at idle, sometimes changes when shifted into neutral or park, and sounds like its low, any ideas where should I start looking?
 
Check for this : run it in neutral or under load, does it quiet down when under load or gaining revs, and suddenly get louder when you come off the throttle? I had one do that on me, replaced it with a fresh Jasper motor, which also developed the same problem after 400 miles. If this sounds like your problem, it's most likely a bad wrist pin.
Thats the one I know best, hope this helps pinpoint (or eliminate) something.

Rich
 
If it's an automatic then another thing to check is the torque converter bolts. The bolts on my 1991 XJ came loose, and I developed a knock similar to what you're describing.

Hope it's that, because it's easy to fix!

:)
 
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