Hello, I have a 2001 460 DA that...

[Flip]

Hello, I have a 2001 460 DA that blows back fuel whenever I fill up.  Somewhere between the tank, fittings, hose, and filler opening.  Has anyone encountered and solved this before?  If so, what was your solution?  

[Tgarris]

Solution is to fuel slowly unfortunately, I’ve heard the air vent is probably clogged/kinked, maybe spiders nest not allowing the air to escape.

[NagsHeadMike]

Likely there is fuel in the vent line. I remove the filler cap and use a plunger over the vent fitting on the the hull to force the diesel out of the line and into the tank. Have to do this for the port tank on my boat that has a long vent hose. I do this before each fill up.

[Flip]

That's an interesting idea. I'll give it a try, although I'm still looking for a fix to the problem. Thanks!

[Steele_y_Tutz]

Having run Heavy Equipment for many years, it's just a normal thing to fuel slowly. I have found our vent lines are really too small and fuel slosches around and fills the line. I use compressed air to clear the line. I know the vent line is clear because I leave a line of fuel when pulling out of the station after fueling. Or going up a hill it will back out of the line. And yes both of our boats are trailered. But a can of air and a stopper with a hole big enough for the straw, should work to blow air back into the line if needed. As for fueling, just don't try to fill it all at once. Slow down and enjoy those fumes.

[NagsHeadMike]

Check for any low spots in the vent line. Vent should be highest point and slope down all the the way to the tank. Any sags/low spots will trap fuel. If no low spots, then likely a bigger diameter air vent line is needed as per Steele'y comment. Another option is to install something like the Attwood Fuel Vent Line Surge Protector. If you do, let us know how it works out.

[Flip]

Still researching, but I've read where this Perko solution may be better ghttps://perko.com/catalog/fills_and_vents/1095/inlet_check_valve___surge_protector_combo_pack/

[Steele_y_Tutz]

I wouldn't put anything just willy nilly into the fuel lines. Looks like PVC coupler. Gasoline will eat that. And my vent line is not 5/8". If it was, then it would vent better and not spill. If your using diesel, it might work. But still if the manufactures don't use them, might be a reason. Both of our boats the vent is below the fill. And that is part of the issue. I wouldn't use those.

[NagsHeadMike]

I do agree, which is why i did not install one. I just use a small plunger over the port vent. Takes a few seconds and works well for me.

[Steele_y_Tutz]

If I was outside with a plunger touching the side of HER boat, I would be in some real serious trouble. I can work on it. I can clean it. And I can use it when she is around. But talk bad about it or do anything "foul" with it, I'm gonna be used for bait. LOL

[NagsHeadMike]

I use a dedicated small yellow sink plunger. It does not look like something you would use elsewhere. Very discreet. Used to use my electric air compressor, but this does the same thing much easier .Some charter boat captains around here will tape a white absorbent pad over their vents. Numerous ways to deal with this.

[Flip]

So you just give the plunder a couple of pumps before filling up? Do yuou place it over the filler cap or the vent?

[NagsHeadMike]

Yes. I place over vent for port tank only which has a long vent line. Rather than pump, I use it to push air into vent. Works for me with 390 MY.

[Flip]

That's interesting NagsHeadMike. So before you fill up, you put the plunger over the vent opening and give it a couple of pumps to break the air lock?