Gas Tank Venting

[mehaffydr]

I have a 2005 with a Tanji Fuel Cell. My tank is taped for the fitting to the fuel cell.

The problem is when I open the valve to transfer fuel the presure from the Main Tank pushes into the Tanji Fuel Cell and forces fuel out the vent. I can stop it by opening the gas cap on the main tank and releasing the presure. But this Sucks when your in a Rally Like Say the IB5000 and fuel is pouring out the vent of the fuel Cell. I am thinking of buying a new fuel cap but at 100.00 just want to be sure that is and will fix the problem. Does the Main tank vent off presure through the cap or by some other means?

Thanks

 

[Ignacio]

Over 85 degrees or so and tank warm?

If so, I never could get the pressure head of the fuel in the cell to overcome the pressure built up in the tank and the spring. I've never thought my cap had issues and made sure all the vent lines were clear. I believe the options are:

• open the cap before the initial transfer (like you're doing...and I'm still doing....with a spare key just for the purpose....usually 10 minutes or so and you can close the cap)
• drill the cap or do an something-ectomy that beeroux tried (risk smelling vapors)
• electric fuel pump (obvious issues....beeroux ended up going this way)
• buy another FJR cap (little chance of change in my opinion...I even got a new one and no change)

 

[Peter Murray]

There is a check valve in the cap venting system, most likely needs to be cleaned. Do a search, some have removed the spring and ball bearing in the cap assembly to solve the issue.

 

[ionbeam]

If you are having a venting problem it's either going to be pinched hoses or the filler cap. To eliminate the filler cap as a suspect for $0.00 read THIS and THIS.

 

[mehaffydr]

This forum just totally kicks *** Thanks for the help I now have something to do tonight.

Mike

 

[Cruzin]

This forum just totally kicks *** Thanks for the help I now have something to do tonight.

Mike

I did the GZ thing, the ectomy works fine and I have never had gas smelling issues unless I did something dumb on day 4 of a Rally and forgot to shut off the fuel cell after filling both tanks

 

[fljab]

If you are having a venting problem it's either going to be pinched hoses or the filler cap. To eliminate the filler cap as a suspect for $0.00 read THIS and THIS.

An aux tank is getting close to "next" on my list; I've read about the venting problems but the solution of reaching up and opening the filler cap whilst riding wouldn't work with me. I routinely ride with a Twisted-Throttle QD type tank bag.

I think I'll look to removing the spring/ball like is exampled here - of those of you that have done that, any issues and/or long term report?

 

[Fred W]

I'm the originator of the Cap Castration technique.

I've never had even the slightest whiff of fuel vapor after the de-balling.

By the way, there is no spring behind the ball in the cap. It is strictly operated by vapor pressure (when it's still in there, that is)

 

[Peter Murray]

I'm the originator of the Cap Castration technique.

I've never had even the slightest whiff of fuel vapor after the de-balling.

By the way, there is no spring behind the ball in the cap. It is strictly operated by vapor pressure (when it's still in there, that is)

My Gen II sure has one or had one , just for the record. The gen 1 must not.

Regarding fuel cell transfer the less pressure buildup in the tank the better the flow trust me.

 

[Cruzin]

I did the ball-ectomy about a year ago or 22K, never had a problem. I just pulled the ball didn't drill it and all works fine :clapping:

 

[Fred W]

I'm the originator of the Cap Castration technique.

I've never had even the slightest whiff of fuel vapor after the de-balling.

By the way, there is no spring behind the ball in the cap. It is strictly operated by vapor pressure (when it's still in there, that is)

My Gen II sure has one or had one , just for the record. The gen 1 must not.

That is interesting, possibly even significant.

You aren't by any chance confusing it with the spring for the key interlock widget, are you?

The part numbers were the same for 1st and and 2nd gens (2005 vs 2006) 5JJ-23602-00-00. The reason that I say "possibly significant" is that I found the part number for both gens has been uprated to 5JJ-23602-01-00.

 

[Peter Murray]

I'm the originator of the Cap Castration technique.

I've never had even the slightest whiff of fuel vapor after the de-balling.

By the way, there is no spring behind the ball in the cap. It is strictly operated by vapor pressure (when it's still in there, that is)

My Gen II sure has one or had one , just for the record. The gen 1 must not.

That is interesting, possibly even significant.

You aren't by any chance confusing it with the spring for the key interlock widget, are you?

The part numbers were the same for 1st and and 2nd gens (2005 vs 2006) 5JJ-23602-00-00. The reason that I say "possibly significant" is that I found the part number for both gens has been uprated to 5JJ-23602-01-00.

There is a strong possability it was the widget spring. I will have to check my parts bag.