Seems the XJ I just bought has rod knock that I didnt notice on my initial test drive before buying it. :flamemad:
I have done some searching here on the forums and as suggested often, I checked the flexplate bolts. I pulled them out one at a time, cleaned and applied locktite to them and then reinstalled making sure they are nice and tight. Didnt fix the knock.
My next step is to replace the rod bearings. I will do all 6 of them just to be safe but I am wondering if I should even bother. What has been the success rate of doing this for others with rod knock problems? Am I just wasting my time with replacing the rod bearings? Should I just drive it till it blows up on me and then replace the engine? Just want some opinions.
The Jeep is an 89 with 190,900something in it. AW4. Plenty of power still, no leaks (nothing serious at least). I have not run a compression test on it yet. No knock at idle, it only becomes audible from about 1500rpm and up, progressivly getting louder. Any suggestions on what else I might try would be appreciated.
Forgot to add that the oil pressure does seem to be good although I am not sure what is normal pressure for the 4.0L going by the factory pressure guage. When cold it is around the 40 psi mark and then drops to about 35 psi at idle and warmed up. Normal driving takes it back up to around 40 to 45 psi.
I have done some searching here on the forums and as suggested often, I checked the flexplate bolts. I pulled them out one at a time, cleaned and applied locktite to them and then reinstalled making sure they are nice and tight. Didnt fix the knock.
My next step is to replace the rod bearings. I will do all 6 of them just to be safe but I am wondering if I should even bother. What has been the success rate of doing this for others with rod knock problems? Am I just wasting my time with replacing the rod bearings? Should I just drive it till it blows up on me and then replace the engine? Just want some opinions.
The Jeep is an 89 with 190,900something in it. AW4. Plenty of power still, no leaks (nothing serious at least). I have not run a compression test on it yet. No knock at idle, it only becomes audible from about 1500rpm and up, progressivly getting louder. Any suggestions on what else I might try would be appreciated.
Forgot to add that the oil pressure does seem to be good although I am not sure what is normal pressure for the 4.0L going by the factory pressure guage. When cold it is around the 40 psi mark and then drops to about 35 psi at idle and warmed up. Normal driving takes it back up to around 40 to 45 psi.
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