Gas In Oil

[wagman]

This was discussed before I believe, but I do not remember the outcome. I've done oil changes at 600, 2600, 6600 and at 10,000 miles there is gas in the oil yet again. I worry about leaking seals but the local Yamaha mech. says the injectors were probably improperly set at the factory. Anyone else experience this problem?

2005 ABS

Wagman

 

[SkooterG]

There never was a resolution that I am aware of. Never was a confirmed problem either that I know of.

Are you sure you are experiencing gas in your oil? And if so, how do you know?

 

[jestal]

del

 

[bikerjazz]

An internal combustion gasoline engine will put some gasoline in the oil, especially on cold starts. On cold starts (even warm weather cold starts) gasoline condenses on the relatively cold cylinder walls when the engine first starts and the piston rings scrape this into the crankcase. As the oil warms up the gasoline is evaporated and purged from the crankcase by the PCV system. Short trips, a short trip just before the oil was changed, etc. will always leave more "gas" in the oil than would be present with very hot oil after a long trip on the highway.

I had a very strong gas smell during one of my oil changes, I was a bit worried. Thanks Jestal for the explanation. I sleep better at night.

 

[markjenn]

If you're seriously concerned, I'd send the oil out for analysis. I believe there are some telltale signes of gas diluation that will easily show up in the analysis report. Unless you have a trained eye (nose?) for the problem, I'm not sure how you could know whether you have a problem or not.

Certainly, a lot of cold starts and short trips (where the engine spends a disproportionate amount of time running rich and at fast idle and doesn't have time to get the oil to full temperature where the gas will evaporate) will increase the amount of gas dilution of the oil. This is the main reason why earlier oil changes are recommended in this sort of service. It's normal.

- Mark

 

[fjrchooser]

Unless you have a trained eye (nose?) for the problem, I'm not sure how you could know whether you have a problem or not.

I should think dropping a lit match into the collection pan would show up any serious gas dilution issue.

:focus:

 

[wagman]

Yes my analysis is only being done by smell. My trips are 40+ miles.

If a lot of peeps experience the same gas reek in their oil I guess I won't be too concerned. I just don't recall that smell in the oil of my last 2 bikes.

Thanks

Wagman

 

[jestal]

del

 

[wagman]

Just changed the plugs @ 9K ... all 4 had perfect color. Thought I might mention the best gas milage I get is in the high 30s per gallon.

Wagman