[lukes_89]

hey guys looking at installing my 2nd tank and found that i have what seems to be a return line that runs to nothing in my engine bay runs along the chassis with everything else, i have found that it runs up into my cab and behind the fuel cover thing inside the cab and this bolts onto the fuel filler neck, had a look and the hose runs into a plastic bowl/ container looking thing and then a hose runs off that into my main tank. my idea was to plum the 2nd tank into that then the fuel will pump straight into the bowl and into the tank or just by pass the plastic container and straight to the tank. my question is what is the plastic thing used for. and if i did hook my system up like that would it cause any problems for me?

[bagnkat]

It's the expansion tank for the fuel system. The end that runs into the engine bay should hook up to your charcoal cannister.

On a side note, I put a longranger fuel tank on my coily. Often, when the fuel tank was full and the weather was hot, fuel would fill the expansion tank, then fill that line that you're talking about until it would eventually leak out the bottom of the charcoal cannister (I believe it's the only vent point). The cannister BTW, is located where fuel leaking from it, can get to the exhaust pipe. I had a larger expansion tank made out of alloy, and didn't have a problem since.

My point is: if you are increasing the capacity of your tank/s be aware of this, and if it leaks from the cannister go a bigger expansion tank.

[lukes_89]

ok well i have a webber so no charcoal canister hooked up which is why i looked at using the line to pump from my 2nd tank to the main tank. what i may do is look at keeping the expansion tank and not bypassing it so then when pumping form 2nd tank to main tank it will fill through the expansion tank. and then if at all the fuel expands it will only pump into the 2nd tank. im only running like a 2psi pump so very slow. but the 2nd tank will only be being used on big trips like to fraser or weeks where there is extra money and really cheap fuel. i may upgrade the canister but i dont see this needing to be done as im not increasing fuel tank size will just be using to refill the tank. ill test this theory and see if the canister over fills or not if it does then i may upgrade the canister or find another way to fill the tank up thanks bagnkat.

[want33s]

Just put a T-piece in the original return line and plumb into that.
Put a charcoal cannister back in the engine bay and hook it up too.
It doesn't just hook to carby, it connects to the tank to trap fuel vapours from expansion on hot days. Fuel vapours kill dolphins!

[lukes_89]

only problem with doing that wont the fuel pump then cause pressure on the returning fuel and then force fuel back up the line back into the carby? and ill put a canister back in lol how much are they jas

[want33s]

lukes_89 wrote:

only problem with doing that wont the fuel pump then cause pressure on the returning fuel and then force fuel back up the line back into the carby? and ill put a canister back in lol how much are they jas

My GQ 2nd tank pumps into fuel return line. Works for me, can't see why it won't for you.

[lukes_89]

ok will look into it thanks heaps