Searcher60 208 #1 Posted April 23, 2017 Hey, a 1996 Onan 20 HP with 401 hours has a noise that sorta sounds like a ticking sound, but not exactly. Definitely not a knock. Any ideas? Doesn't sound like any valve tick I have ever heard, but maybe. Thanks in advance. Share this post Link to post Share on other sites
rmaynard 14,932 #2 Posted April 23, 2017 Where does the sound seem to be coming from, front cylinder area or the rear? Share this post Link to post Share on other sites
Searcher60 208 #3 Posted April 23, 2017 31 minutes ago, rmaynard said: Where does the sound seem to be coming from, front cylinder area or the rear? Sorta center front. Share this post Link to post Share on other sites
Cee245 756 #4 Posted April 23, 2017 Is it a consistent tick? When you rev the engine does it tick more frequently or less/same? Share this post Link to post Share on other sites
Searcher60 208 #5 Posted April 24, 2017 (edited) Consistent at all rpm. Noise speeds up and down with engine. Can't hear it wide open due to exhaust. Edited April 24, 2017 by Searcher60 Share this post Link to post Share on other sites
ericj 1,576 #6 Posted April 25, 2017 the ticking noise I've heard on onan engines came from 3 different issues. One of the first ones was a loud valve ticking on a 97 416-H, took my buddy to look at it and he walked away scared of the noise. I did some wheeling and dealing between my buddy and the seller , by fixing his broken A/C system. anyways I brought it home and pulled the intake and exhaust off and found the cap fell off the valve stem some how. I forget which valve it was, last year I bought a 520 and the owner said the motor was junk. dragged it home and pushed it off the trailer and left it sit till a month ago. started checking it out, had 110 psi per cylinder so I got it running, but it had a knock to it that seemed to be getting louder each time I ran it. Finally found that all of the bolts on the bearing plate behind the pto where barely hand tight. tighten the bolts up and no more knocks, something easy enough to check for yourself. and the last I found, but can't remember any exact specific case but an exhaust leak could cause a tick noise, so that's something else to check for. good luck let us know what you find, may help somebody else down the road eric j 1 Share this post Link to post Share on other sites
WHX?? 46,943 #7 Posted April 25, 2017 @ericjmight be on to something there ...or maybe just valve lash needs adjusting? On my honey do list as well! 1 Share this post Link to post Share on other sites