If you trace the vent hose toward the back of the bike you will find a small plastic one way valve. Get rid of the valve and make sure your hose is not kinked anywhere. I had that valve go bad on a 96 Fatboy.

 

Cheers Martin. I'll have a look.

 

Vacuum is needed for any fuel to flow

Also, FYI






Your pressure relief vent is here? (below)...yes?




Also you can check your vented side gas cap (one-way from OUT to IN) vent by sucking (...really) on the bottom of cap to see if the check valve is allowing air to pass.

 

Cheers for that. Where do you find those exploded diagrams, they're very handy. I've only had to take the left hand tank off so I'm assuming the vapour valve and pipe are on the right one. Only filled up twice since I bought the bike (British winters aren't worth riding in for the most part) so haven't even noticed if there is a pressure relief vent. Thanks very much for the input, it's muchly appreciated.

 

That's the cross over to stabilse pressure left to right side.

 

I've got to say that the people on this forum are very helpful. It's a pleasure to be a member.

 

Yep, I could see that when i researched the exploded view of that softail tank. Since the the left tank doesn't use a vented cap, that vent/vapor crossover is the only means provided for the left tank to be exposed to atmospheric pressure. Isn't that left cap also have Left-handed threads? I haven't handled any harley twin/dual tanks (softails), but that doesn't matter...once you know theory, you just apply it wherever you need it.

Hey Gotme, if PM your email addy or post here...I have a gift for you.
.

 

Yes, left turn tread. This way when filling the tank your not putting the vented cap on the wrong side.
If you've got full tanks or over filled and the bike is on the jiffy stand during the warm weather the gas expands and could leak out the vent if it's on the left side.