R25SC Fueling Problems

[TonyM]

Hi All,
I have been having a really difficult time fueling the Molly M this summer.
The problem is that fuel comes out the vent after adding only a few gallons.
I have blown through the vent before fueling and it is clear.
I have to fuel really slow...what a pain when you want to add about 70 gallons. 🙁
The worst event was refueling this morning in Astoria with the large nozzle before my return to Portland.
When I fist got the boat I had the same problem and I found the vent line was squeezed. I loosened the Ty-wrap and solved the problem until I got down here on the Columbia River this spring and summer.

Thanks in advance for any advice you can offer
Tomy Marshall
Molly M
2010 R 25 SC

 

[TonyM]

I traced out my fuel lines and I found low spots in both the fill and vent lines where fuel could accumulate.
THEORY...
As the tank filled the diesel foams and as the air and some foam traveled up the vent line, eventually the foam accumulated in the low spot in the vent line as a liquiid instead of flowing back to the tank. The pressure from the tank would push fuel out the vent.
THE FIX...
I found the low spot to be in a spot aft of the water / exhaust mixer where it could not be seen. I re-routed and shortened the vent line about eight inches.
On the fuel fill line I cut a few ty-wraps so the line is going down hill to the tank.

I still have about 50 gallons onboard so a test of my theory and fix is still sometime in the future unless I make another long river trip.(fishing does not use much fuel)

Tony Marshall
Molly M
R-25 SC