Fuel New gas tank leaks ??

[88-90ConVerts]

I have a 88 LX convert 5.0 and I recently replaced the gas tank with a new sending unit and new 255lb fuel pump, I bought all new seals with new locking rings. Before when I would fill the gas tank up it would leak out the top where the fuel pump is located. I made sure that the new o-ring would seat properly before I installed the new tank. When I filled up is was fine no leaks, but when I topped off and filled it completely to the top it leaked out some where the fuel pump is not where the sending unit is. Is it the o-ring not fully settled yet? I would like hear if anyone else has to his problem thanks.

 

[General karthief]

There is a couple places on top for leaks. Make sure the O ring didn't roll over or get pinched, the vent tube nipple could be leaking also.

 

[88-90ConVerts]

There is a couple places on top for leaks. Make sure the O ring didn't roll over or get pinched, the vent tube nipple could be leaking also.

The O-ring on top I made sure didn't roll over also I put a new grommet and vent tube when I replaced the gas tank, When you mention leaking out the nipple are you talking about where it inserts Into The Grommet or where the hose connects on to the nipple?

 

[General karthief]

Both, did you replace the filler neck gasket? Also check the hoses on top. Are you sure the leak is on top of the tank? Or are you smelling fumes.

 

[88-90ConVerts]

Both, did you replace the filler neck gasket? Also check the hoses on top. Are you sure the leak is on top of the tank? Or are you smelling fumes.

Yes I replaced the grommet on the side the sending unit with new o-ring and lock. Plus the gas tank is brand new, and yes it is leaking on top only when I fill it completely full and I mean completely full. That's the only time it leaks if I just fill it up normal without making sure it's completely topped off it doesn't leak seems like when it gets to a certain point on Top that's where it's coming out at and the only thing on top is the O-ring and lock where the fuel pump is and the fuel vent.

 

[General karthief]

Your not supposed to 'top it off'. It's likely overflowing out the vent.

 

[88-90ConVerts]

Your not supposed to 'top it off'. It's likely overflowing out the vent.

That's what I figured that's the only time it leaked was when I top it off completely full. So do you think it's coming out of the vent because the vent has a hose that connects on to the nipple I don't see where that would leak out at unless it came out the grommet, but that's new.

 

[General karthief]

When you 'top it off' your filling the tank to a point above the vent so it will bleed out someplace, usually it would fill up your vapor canister, you may have a hose seeping, check the vapor hose from the tank to the canister

 

[88-90ConVerts]

When you 'top it off' your filling the tank to a point above the vent so it will bleed out someplace, usually it would fill up your vapor canister, you may have a hose seeping, check the vapor hose from the tank to the canister

Thanks for help, are you talking about the charcoal canister? And I may have not mentioned this earlier the only place I did notice the leak was on top and it only leaked out a small puddle then stopped.

 

[General karthief]

On top of the charcoal canister or the gas tank

 

[88-90ConVerts]

On top of the charcoal canister or the gas tank

Thanks for help.

 

[HotFox]

I have experienced a leak around the sending unit because I had to beat the old ring off. This distorted the opening enough on the factory tank that the new ring and seal did not seal properly. It leaked bad so I had to pull it back down and reshape the mouth with a plyers to put the correct amount of pressure on the seal.

 

[General karthief]

He has new tank, but the opening could still be distorted enough to be a problem, I'd pull that tank and make sure all is good on top anyway but thats just me, I've only dropped a couple dozen tanks, I need more practice, but only with full tanks, empty ones are too easy.

 

[HotFox]

He has new tank, but the opening could still be distorted enough to be a problem, I'd pull that tank and make sure all is good on top anyway but thats just me, I've only dropped a couple dozen tanks, I need more practice, but only with full tanks, empty ones are too easy.

Yes I get that he has a new tank but the that is being produced today this is very likely the problem. As I bet my factory tank is tougher then what he has.

 

[jrichker]

First of all, pull the tank put and set it on the ground. If you are creative, come up with some caps and plugs for all the connections and openings except the vent. You are going to use it to carefully pressurize the tank. Get a small paint brush, some liquid dishwasher detergent and a plastic cup half full of water. Mix up some soap solution and apply it with the paint brush around all the openings in the tank. Carefully apply low pressure air -2-4 PSI to the vent line and watch for bubbles around the tank openings that you have capped or plugged. JB Weld does a great job on fixing fuel tanks once you know where the leak is.

 

[General karthief]

Yes I get that he has a new tank but the that is being produced today this is very likely the problem. As I bet my factory tank is tougher then what he has.

Yea, your probably right, I've never dealt with a new tank.