Blue smoke out of my onan!?

[papaglide 542]

Well I was out riding my 1996 416-8 around the yard when about 15 minutes into my run I started to notice that my exhaust had a bluish tinge to it and there was quite a bit of it. I am not quite sure what is wrong with the engine. Burning oil for sure but why? Thanks. If this helps there are 956 hours on the tractor.

[Hodge71 665]

Not sure what to tell ya on that Papa. I have a '96 416-H with over 1700 hours on it and it doesnt burn a drop. Although I have a sneaking suspicion that the PO's Dad had it rebuilt at some point. Its either that or I have the luckiest Onan made with how these things chuck valve seats around 1000 hours. Is there any chance that you might have sme oil leaking past the valve guides? Has the motor been opened up ever for decarboning or anything else? 

[leeave96 490]

Is the crankcase over filled with oil by chance?

Edited April 18, 2013 by leeave96

[papaglide 542]

Maybe.I did do an oil change on it. I thought that I put just enough in it to the full line. Maybe I put in too much? I will check it when I get out of work. If it is overfilled, should I just drain some? What damage could I have done to the engine? Thanks.

[leeave96 490]

Reason I said overfilled is I did that to another color tractor of mine and got some blue smoke - just a few puff's, but it made me stop and check things and I corrected it.  I just opened the drain a bit and let some oil out.  If I let to much out, I'd just add some fresh oil to bring it back to level.  I don't think I did any harm to the engine - seems to be running OK

[papaglide 542]

Thanks for the advice. Hopefully this is all it is!

[wheeledhorseman 579]

Not sure what to tell ya on that Papa. I have a '96 416-H with over 1700 hours on it and it doesnt burn a drop. Although I have a sneaking suspicion that the PO's Dad had it rebuilt at some point. Its either that or I have the luckiest Onan made with how these things chuck valve seats around 1000 hours. Is there any chance that you might have sme oil leaking past the valve guides? Has the motor been opened up ever for decarboning or anything else? 

 

From what I've read on the forum the 16hp doesn't suffer like the others seem to. Mine has also passed the 1700 hour mark and runs beautifully (now I've sorted the manifold leak) and doesn't burn oil. So there's every chance its something simple like oil level. Good luck.

Andy

[papaglide 542]

Thanks, Andy!

[CRE1992 135]

Like others said check the oil level, and also check the crankcase breather to make sure it isn't clogged up

[papaglide 542]

Thanks everyone! I will check it out tomorrow and will definitely give an update.