RyanG Posted August 19, 2015 Share Posted August 19, 2015 Anybody run in to mystery knock at idle on 5.0. I have it down to the passenger side valve cover, removed and did not see any problems with adjusters or followers. Removed the belts, cancelled cylinders etc. with no change in noise. Hotline said possible issue with cam cap alignment or cylinder liner distortion. Just wondering if anyone has run in to this yet. This is the first time I have worked on one of these so not familiar with common issues. Note: The knock is only at idle, goes away as soon as rpms raised. Quote Link to comment Share on other sites More sharing options...
ktmlew Posted August 19, 2015 Share Posted August 19, 2015 Anybody run in to mystery knock at idle on 5.0. I have it down to the passenger side valve cover, removed and did not see any problems with adjusters or followers. Removed the belts, cancelled cylinders etc. with no change in noise. Hotline said possible issue with cam cap alignment or cylinder liner distortion. Just wondering if anyone has run in to this yet. This is the first time I have worked on one of these so not familiar with common issues. Note: The knock is only at idle, goes away as soon as rpms raised. I would check oil pressure at idle and just above? Quote Link to comment Share on other sites More sharing options...
batmantech Posted August 20, 2015 Share Posted August 20, 2015 Had one awhile back it had one collapsed lash adjuster. Quote Link to comment Share on other sites More sharing options...
YukonTyler Posted August 20, 2015 Share Posted August 20, 2015 I've heard of them with the cylinders having excessive runout - never seen one myself though. Quote Link to comment Share on other sites More sharing options...
RyanG Posted August 20, 2015 Author Share Posted August 20, 2015 I checked all the lash adjusters and everything looks ok. I heard about the run out too. Another tech had the same noise, hotline had him replace the head with a new set of adjusters and followers for the same noise which fix the issue and hotline is saying the same thing to me. I'll keep you posted. Quote Link to comment Share on other sites More sharing options...
Matt Saunoras Posted August 20, 2015 Share Posted August 20, 2015 We had a 5.0 head sent to the machine shop and they found excessive exhaust valve guide wear. I forget what the original complaint was. I just remember that there were no guides available from anyone. Quote Link to comment Share on other sites More sharing options...
cbriggs Posted August 24, 2015 Share Posted August 24, 2015 I had one with a knock that I could hear the loudest in the rh exhaust manifold studs with a stethoscope. A cylinder head fixed it. Found what looked like severe galling on one of the #4 exhaust valve stems. I think the valve was hanging just enough to come off the cam lobe and slam shut, but not enough to hit the piston. Quote Link to comment Share on other sites More sharing options...
RyanG Posted August 28, 2015 Author Share Posted August 28, 2015 Put an assembled head on it and drove it, no noise. Quote Link to comment Share on other sites More sharing options...
forddieseldoctor Posted October 11, 2016 Share Posted October 11, 2016 Was it a continous noise or intermittent? Quote Link to comment Share on other sites More sharing options...
RyanG Posted October 13, 2016 Author Share Posted October 13, 2016 Noise was intermittent. After i put the head on it was gone for a while and came back with the knocking noise from cylinder liners. I ended up doing a short block per ford. I never found what caused the noise in the head, i just replaced assembly. These were 2 different noises. Its hard to track down the causes due to the amount of things it could be on these engines. Quote Link to comment Share on other sites More sharing options...
forddieseldoctor Posted October 14, 2016 Share Posted October 14, 2016 I thought I had one. Turned out to be a tight a/c compressor that melted the clutch. Quote Link to comment Share on other sites More sharing options...
YukonTyler Posted October 14, 2016 Share Posted October 14, 2016 Related to that, I've seen small rocks in the A/C belt (lodged between the ribs) cause an intermittent knocking noise. The intensity of the noise is affected by the state of the clutch. Quote Link to comment Share on other sites More sharing options...
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