Is anyone aware of there being an ongoing issue with fuel tank deterioration in '89 Offshore? I'm powered by '98 Yamaha OX66 2 stroke, constant stalling at low speed after a period of use. Runs fine initially at high speed. Been in shop twice, not solving issue. Fearing that fuel tank may be on its way out causing clogs in the system. #frustrating summer
Offshore fuel tank issues? Low speed stalling
- Thread starter jwsonas
- Start date
Yeah, I have Racor fuel water separator filter w/ clear bowl, no sign of sediment or water there...
Parthery
GreatGrady Captain
Check the low pressure fuel pumps and the VST tank. When was the last time the VST was serviced?
LP pumps are not expensive or difficult to replace, if they are leaking.
LP pumps are not expensive or difficult to replace, if they are leaking.
VST was the first thing they serviced on it, thinking it was the issue...alas, the problem continues. Low Pressure pumps, you say??...
Low pressure fuel pumps... I would put money on this.
I had the exact problem with my '99 ox66 200 a couple months ago. Turns out, one of the low pressure pumps had a hole in the diaphragm. 15 minute fix.
I had the exact problem with my '99 ox66 200 a couple months ago. Turns out, one of the low pressure pumps had a hole in the diaphragm. 15 minute fix.
Parthery & CleanupRequired-
Just got the callback from the marina...they replaced all three Low Pressure Fuel pumps and gave her a test run, tell me it's ready to go. Good call!!
And many thanks. Hopefully that's it for the season...
Just got the callback from the marina...they replaced all three Low Pressure Fuel pumps and gave her a test run, tell me it's ready to go. Good call!!
And many thanks. Hopefully that's it for the season...
Parthery
GreatGrady Captain
Not sure if your mechanic is a certified Yamaha guy (or gal), but the LP pumps are an obvious trouble spot with these motors. And they are easy to check - 2 bolts to loosen and then squeeze the primer bulb and watch them. If fuel leaks out the back, the diaphragm is bad and the pumps need to be replaced.
In any event, glad for you that it's fixed. Enjoy the season...
In any event, glad for you that it's fixed. Enjoy the season...
Parthery said:
Sometimes these pumps degrade in performance but the rear diaphragm doesn't leak. I have had this happen to my motor. Folks should also note that the pumps, 2 or 3 depending on model motor are connected in series. Just replacing one may not help or might mask another bad pump. It is best to replace all at the same time.
It is also a good idea as part or annual maintenance to check that the pump housing screws AND mounting bolts are tightened to spec. They like to loosen up.