Best way to flush fuel out of oil?

Hey guys!

So after chasing down an issue of fuel being in my Oil, it turns out the float needle isn't leaking and the carby is functioning as it should. It was an issue with the Accellerator Pump causing fuel to leak over as the throttle was constantly being turned to try and start the bike whilst it had a valve issue. 


So, I have since replaced the filter and dropped the oil twice. However it is still a bit too diluted and smells of fuel. I had left the dipstick off to try and vent the frame. I know there isn't more fuel getting Into the oil as the level isn't changing and it isn't getting worse. 


What is the best way to flush it all out? Buy 5L of cheap car oil, warm the bike, drop the oil. Rinse and repeat? Or use an engine oil flush additive? Or both? 

I know I need to get another oil filter again, should I put that in after I have flushed it out, or before? The current filter has had 1 oil gone through it and dropped and is currently on its second lot of oil. It has done maybe 20km since then. 



Try one oil/filter flush, toasty warm up, then easy ride.  If your oil does not pass the Sniff Test,  repeat oil/filter.  Fuel in the oil will give a rich mixture as it evaporates and gets sucked back into the airbox.  Any decent diesel truck oil is fine. 

BTW, a putt around town will not burn off fuel diluted oil.  It takes miles to get the oil hot and fuel to evaporate.  Plan a nice 70 mile ride to somewhere for lunch or dinner, bring some mates.


Ride it hard and it'll evaporate out and away.

It's no issue to have some fuel in there. Any 4 stroke ridden at low loads too often also gets fuel diluting the oil.

Well I picked up another 2x filters today and another 4L of oil. I'll go for a spin in the morning to get it warm, drop it out and put some new stuff in, then I have a trip planned to some forest trails nearby for a few hours. Then I'll give it another change after that and see how it goes. 

make sure you are doing a full oil change, the frame and the crankcase

24 minutes ago, 74jimbo said:

make sure you are doing a full oil change, the frame and the crankcase

I wouldnt think there was any other way, haha. 

Thanks for the helpful info guys! 

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