Onan oiling system Q's, tick tick

[fasteddie313]

Is this one of those deals where there is an anti-reversion check valve in the oil filter to prevent the oil galleys from draining back to the pan on shutdown?


I ask because when the genny shuts down it makes a lot of dripping and liquid flowing noises as oil rushes back to the pan, and especially at startup when hot it's making some ticking/clacking/knocking noises that I don't like.. They almost go away after it's running for a bit though. Yes it has oil in it.. How quiet are these supposed to be as far as valvetrain noise etc.?


I was able to grab ahold of the crank in an effort to induce rod knock by rocking it back and forth by the flywheel and there is a small amount of play in the rods somewhere but I don't really know how it's supposed to feel, how tight spec is etc.. It's far from the worst i've seen, far..


Sorry for all the Q's but I have an installation manual, a parts manual, but nothing resembling a service manual..  The manual says it is a 6500W onan 2 cyl rated at 14hp and the clock only reads 590 something hours..


Is there a way to do valve lash on these engines, and are these the ones with the ignition timing off a cam? What oil? I'm thinking heavy 10-40 diesel oil? The silly books I have don't even say what kind of oil it takes..


If it is a rod, heaven forbid, how rebuildable are these bottom ends? Run it till it blows up or fix it? I don't think it's about to pop but doesn't sound 100%..

[Bnova]

I'd take a look in the members section, there's more than likely a service manual for it there.

[fasteddie313]

Anyway I see that there are lash adjustment nuts in the middle of the pushrods, I guess I'll play with those and see if it relieves the noise if I put them to spec..

Other than the manual, does anyone have any ideas as to the described symptoms? Does yours make a lot of liquid noises when it's shut down? How tappety does yours sound?

Also I see a lot about the main bearings and cam bearings but nothing about rod bearings. I take it there are no rod bearings and any wear there requires replacement of the crank and rods?

It says there is supposed to be an oil pressure gauge in the "upper right hand corner of the engine shroud" whatever that means. I'll see if I can't find that but I did not notice one..

[gpw9552]

I have a PDF copy of the NHE Service Manual I can email to you. 

[Rickf1985]

Yes, the PW gets me into the members area but it won't unlock that document at mediafire where it asks for a PW again..
If you are a member try that DOC and see what it does for you, just click that link, see if your PW works on it..

That is for the operators manual but if you go to the service manual you can download it. You will need to know which spec number you have since you have a choice of two manuals. I checked and both are available for download.

[DaveVA78Chieftain]

I have corrected the links to all manuals for the
Onan BGM, NH, and NMH generators in the Free Manuals section of the Member area.


Please let me know if you come across another
Onan or Kohler Generator linking issue.
Actually, any error in the Member Area.

[M & J]

WTG DAVE!