Fuel cell issue...

[wasted wages]

how do you keep a fuel cell from burping gas out when it's full ?

My fuel cell pukes gas out of the vent line when the cell is full and the sun begins to warm up the tank...

I've had 6 people come in today and tell me..... you truck is leaking gas....

 

[Bent77]

Wow, mine has never done this, and it is in the bed on the K5. Without elevating the vent higher to prevent a siphon effect, some type of cover to prevent it from heating and expanding would be my guess.

 

[wasted wages]

I topped off the tank this morning ( cold ) and it was parked on a slight incline...away from the vent.... ( my cell is in the bed of the truck).... As soon as the sun started to warm up the tank, it spilled about a beer cans worth of fuel on the ground from the vent line...

I know not filling the tank up to the filler neck is the obvious fix, just wondering if anyone else has run across this and what they did to correct it..

 

[ChrisPerry]

I haven't done it, but an expansion tank on the vent line would probably work. Let us know what you do so we can copy.

 

[Smokinthehippies]

: Let us know what you do so we can copy.

Yes please.

What about putting in a one way check valve in the vent line?

 

[Avery4jc]

My fuel cell always pukes fuel out of my rollover/breather valve when we go wheeling because of the elevation change. If I leave it a gallon or so shy of full it seems to be fine but if I fill it all the way up it'll puke it out.

 

[bp71k5]

You could add two vent lines, that way it would take twice as much liquid to overflow. Putting a second one on the opposite side of the tank might also help let the tank still vent in case the first one is plugged by gas when your parked on an incline.


-Brian

 

[ryoken]

how do you keep a fuel cell from burping gas out when it's full ?

My fuel cell pukes gas out of the vent line when the cell is full and the sun begins to warm up the tank...

I've had 6 people come in today and tell me..... you truck is leaking gas....

that's the reason when we winterize boats, we only fill the tanks 7/8.... if ya fill em, you'll walk around the marina yard in the spring watching em puke fuel out the vents from the expansion..

which, I'm sure in a vehicles case, an expansion tank in the vent line would solve it...

 

[wasted wages]

thanks for the responses.....

here are my thoughts...... a check valve has to be in the direction of flow to let the pressure out of the tank or else it will never vent.....blocking the vent by reversing the direction will cause the tank to over pressure... not good.


dual vents....I have this on my buggy,,,, I ran the two vent lines up the roll cage tubing and tee'd them together... and put the vent on the tee also...this worked well as the fuel would rise up one tube on inclines and run back down the other side back into the tank...but this one I'm having the problem with only has one vent and is in a daily driver street truck...


expansion tank....seems to be the next best choice....would have to be above the tank to allow for gravity feed back into the tank...

what say the brotherhood.....

 

[bp71k5]

expansion tank....seems to be the next best choice....would have to be above the tank to allow for gravity feed back into the tank...

Yes, it'd need to be able to drain back down otherwise it would eventually fill up and be useless. Another option might be to replace the vent line with a larger diameter hose, which would act as a type of expansion tank.




-Brian

 

[ChrisPerry]

Definitely would have to be higher than the tank. Do you have a cage in said truck to attach it to?

 

[Fordum]

Or you could plug the line and use a vented gas cap......

 

[Avery4jc]

Or you could plug the line and use a vented gas cap......

That's essentially how my cell is setup and it just blows it out the vent. The fitting welded on top of the tank that's supposed to be a vent line is capped off and I drilled a hole in the top of the tank and used a vent/rollover valve.

 

[Fordum]

That's essentially how my cell is setup and it just blows it out the vent. The fitting welded on top of the tank that's supposed to be a vent line is capped off and I drilled a hole in the top of the tank and used a vent/rollover valve.

Uh-oh, I may have spotted the problem.
I have seen several different setups for vents. And a lot of them had baffles or air bubbles attached to the vent.
For instance, on my old tractor there is a hole in the top of the tank. Then there is a bubble shaped piece of steel with baffles welded over the hole.

Then another hole in the bubble.

I'm thinking that the original vent connection might have something inside the tank to prevent whats happening.

But, either way, a large can with the line from the tank going in the bottom, and a line hooked to a vertical wound coil out the top should handle it.

 

[ktmoutfront]

I would run it down and put a bung on the tail pipe. Have your boss stand behind the truck when you start it.

 

[90'K5]

I ran my cell vent through the stock vent line, zero puking - even after rolling it.