oil on plugs

[lil bubba]

I have a '08 Yamaha 70 2 stroke. I was using off brand reg. no ethanol and getting oil buildup on plugs so bad it was like tar almost....I started using shell reg. ethanol with stabill and went a year with the same plugs and never cleaned . no oil buildup. shell came out with 89 octane regular ethanol free and I started using that and continued stabill and in less than 3 months plugs fouled with oil thick as tar again....drained tank and put in shell ethanol with stabill and after running ten minutes motor running like new again.....main problem was running rough when idling , after high speed jet kick in it ran fine...all 3 cylinders foul the same with the non ethanol gas...anybody else experience this...I only have a 6 gallon tank and I never use gas over 3 weeks old...

[DannyI]

Not sure but I would try different gas station, regular gas even ethanol free should not do that. I worked in a refinery lab and we tested for "gum" and had a spec to pass. Sounds like Shell has a different spec on gum. With all new regs, no gas should have gum actually.

[jldsc]

did you happen to try higher octane fuel? I would only run super ethanol free in my 40 yamaha and didnt have any trouble.


Sent from an Apple Tree..

[lil bubba]

man this is like tar...I spray the plugs with carb cleaner and it like peels off .... it doesn't dissolve it... I thought maybe it was the cheap non ethanol gas station but when the shell station started selling non ethanol 89 octane I started using that and it tars back up again....the regular shell with 10% ethanol makes it run like new almost immediately ... I don't think I have the only motor with this problem....maybe I just pay att. to these things more cause I was a mechanic but it just don't seem right...

[jldsc]

what oil you using?


Sent from an Apple Tree..

[lil bubba]

yamalube,,,,,omc....doesn't matter

[DannyI]

It has to be the gas, I would definitely try another station without the ethanol. But here is the deal, just because it is a Shell station does not mean it is Shell gas. It could be from any refinery in your area. I worked for CITGO Refinery in Lake Charles, and we and Conoco Refinery here in LC supplied gasoline to all stations, regardless of brand. Thats just the way it is. So once again, it could be that the "recipe" for that particular brand that was/is sold to that Shell station, is not what it should be. The only way you can tell or do anything about it, is to complain to the station manager, ask who they are purchasing gasoline from (vendor), call them and tell them what is happening. They "should" sample the tank, have it tested, or provide a sample to the refinery they buy from to check it for "gum". They should provide you with an answer. If they won't, call the Shell Refinery public relations department, tell them what is happening.

[Goooh]

Originally Posted by DannyI

It has to be the gas, I would definitely try another station without the ethanol. But here is the deal, just because it is a Shell station does not mean it is Shell gas. It could be from any refinery in your area. I worked for CITGO Refinery in Lake Charles, and we and Conoco Refinery here in LC supplied gasoline to all stations, regardless of brand. Thats just the way it is. So once again, it could be that the "recipe" for that particular brand that was/is sold to that Shell station, is not what it should be. The only way you can tell or do anything about it, is to complain to the station manager, ask who they are purchasing gasoline from (vendor), call them and tell them what is happening. They "should" sample the tank, have it tested, or provide a sample to the refinery they buy from to check it for "gum". They should provide you with an answer. If they won't, call the Shell Refinery public relations department, tell them what is happening.

Could be the am exact same gas at shell that was at the first station he was using non ethanol? from?