gas in the oil ??

[Serge]

When I was buying my honda 919 (2002 with 20k miles) I took it to the dealer for a check up and mechanic said that there is some gas in the oil, but it is not a problem.. Yesterday I changed oil after 3 000 miles and it was not viscous at all and I think I could smell a gas in it..

The FI light is off and bike rides fine, though it is kinda on a lower end of gas mileage .. I was checking oil level and it did not change much ...

How the gas can get in the oil in FI bike? Leaking injectors? Should I do something about it or am I just being paranoid ?

THanks!

[Sane_Man]

Are you the type that lets your bike warm up for 15 minutes with the enrichment circuit on full before you ride it? If so, that could be your problem.

[Serge]

no, I do not touch the choke at all on this bike ..

[caponerd]

no, I do not touch the choke at all on this bike ..

Does the bike use much oil?

I'm not familiar with the type of fuel tap on a 919. Is it the type that you don't have to shut off? Or does it have on-off-reserve positions?

If you leave the fuel on overnight normally with the on-off-reserve petcock, that's probably what's causing it.
Well, that and slightly leaky carburetor float chamber valves. If everything in your carbs are perfect, it shouldn't matter if you leave the gas on, but if the tips of the float needles are worn, then fuel is going to fill the float chambers, and leak down into the cylinders where it will leak past the piston ring gaps and into the crankcase.

A very rich fuel mixture will also cause fuel to get into the crankcase. This is more serious because the raw fuel going into your engine can wash the oil off the cylinder walls and cause premature wear on the rings and cylinders. That's why I asked if the bike is consuming much oil. That's a sign that the piston rings and cylinders are worn out.

Oh, and if your petcock is the type that opens from engine vacuum (Kawasaki's are like this, don't know about Hondas), it's possible that it's stuck open.

uh-oh. Disregard all that about float needles, petcocks and stuff. I missed your comment about FI.
How is the fuel economy. If your fuel injection is so far off that you're getting gas into your crankcase, your gas milage will be crap. Like in the 20's. With a fuel injected system, that's the only way I can imagine fuel leaking into the crankcase, since there's no fuel flowing at all when the engine's not running.

[joespeedfast]

Your bike does not have a "choke" per se, more a "fast idle" control. ECU does all of what little auto enrichment occurs based on coolant temp, intake air temp, running time etc.
Could be dirty leaking injectors, could be fuel pressure(too rich). Does it have a PowerCommander? Could have been a one-time thing fom sitting. Also, EVAP emmisions cannister could have a problem and suck up feul which could work its way back into the intake. :dunno

[Bronto]

You know how there's a ventilation hose on the crankcase. Sometimes on the valve cover also. These lead back to the air box or carbs/throttle body. It's for gas fumes that get into the crankcase.
You know how dirty the oil gets. These are normal :|
Gas and other combustion by products make there way into the crankcase, Via the valve stems and getting past the piston rings.

Carbs or fuel injectors adjusted or by malfunction to rich condition. Does increase gas contamination in the crankcase.

Loose valve stems or worn piston rings increase gas contamination. These are usually from mileage wear.

Suggest change the oil at 3k miles then change oil and oil filter at 6k miles. It's happens to everyone, but not all of us have our noses in the old oil :laughing

[Serge]

Thanks a lot for the replies ! I guess I was too much concerned about it.. Yeah I think 8000 oil change interval recommended by Honda for this model is way too long.. I will stick to new oil every 3K new filter every 6K... I do not have Power commander and evap canister.. It is also missing a PAIR system which is blocked off - I wonder if this would contribute...