Hi guys I just bought a 1976 F-250 for 500 bucks. The guy said it had a rod knock so I went along with his diagnosis to get this one home as it has a mint body. I got it home and noticed the water pump was making a ton of noise so I replaced it and it was really pooched. Now I got all back together and its still making noise. It is a ticking noise almost like sticky lifters but a little bit louder definitely not a rod knock. So I poped the valve covers off and ran it. I noticed one valve was not opening as far as the others. Could I have found my problem? I am thinking its either a bad lifter or flat lobe on the cam. My question to you guys is that could a flat lobe or bad lifter cause such a racket???
Does the knock go away at rpm,how's the oil preesure? I have a 74 F350 with a serious knock that goes away at 1200 rpm, and I've been told it's the crank walking in the block. The thing is it has been making this noise for 20,000 miles and not getting worse. I don't think a valve or lifter problem would make the noise. Good luck
a dud lifter or cam will definetly make lots of noise! if the valve not opening as far as it should it could be dud lifter or dead lobe for sure. checking for wich one is the fun part on the fe motor! first take the rocker shaft off and check it is ok, then compare the push rod from that valve with the other push rods to make sure it is ok, if that is all good you will need to remove all pushrods and intake manifold to remove the lifter and replace it if its no good. check the base (cam end) of the offending lifter to see if it has worn concave, if so the cam will be no good either. any probs just contact me. cheers.
I agree with the thoughts of the other guys and i would check those for sure.
unfortunatley,i had a noise very similar in my Boss 302 engine a couple of weeks back.it was still running and i was able to drive it from where i was to back home.30 miles.i could not believe it when i pulled the head off and found a valve broken in half.the engine still ran pretty well considering.It was just making the "tick tick" sound like lifter noise.
hope this helps.good luck.pete