Oil in fuel line?

danie

Petty Officer 2nd Class
Joined
Apr 11, 2005
Messages
154
Hi all<br />I have a 1988 Mariner 90 3cyl which gets serviced every year by agents and runs great but has one problem. Sometimes when throttling back to neutral after running at wot, the motor would smoke and stutter for a few seconds when going forward again. <br />A fuel filter with a glass cover is fitted on the motor side of the primer bulb and I also noticed that when the motor is switched off, two stroke oil must be leaking back into the fuel line because the color of the fuel in the glass filter changes to that of a premix (takes about 3-5 minutes). <br />The motor starts easily enough but I get the impression that there is always a "wrong" mixure which must be burnt first before I get full power and you will agree that a waiting skier does not appreciate that.<br />Weather is great. Leaving tomorrow for 6 days of skiing. <br />Any suggestions plse?<br />D
 

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: Oil in fuel line?

When running at WOT the pump is mixing at a greater rate than idle, so when you throttle back quickly the fuel in the line is mixed richer till the engine burns it.-Bob
 

danie

Petty Officer 2nd Class
Joined
Apr 11, 2005
Messages
154
Re: Oil in fuel line?

My thoughts exactly but as the oil/petrol gets mixed close to the carburators, isnt there suppose to be a valve/diaphram to prevent the mixed petrol from running back as far as the filter/bulb??<br />Thks<br />D
 
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