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MG MGB Technical - Fuel surge

I have identified a problem with my GT.
At track days I think the fuel is moving away from the pickup, especially right hand bends. I have the early type tank with outlet on right side.
I would like to remove the tank and cut a hole in the top through which I could fit a baffle maybe with a trap door to limit fuel moving away from the pickup. Then weld the top back on.
This would entail some grinding and welding.
Is there a safe way to cut and weld the tank without it exploding or catching fire.
It would probably be a good idea to empty the petrol out first then wash it with deturgent.
Is there a safe way? or do I need to start with a new tank.
I think the later tanks had baffles fitted but I am not sure if they will be OK under extream cornering conditions.

Thanks in advance

Mark

4.6 GT V8
Mark

Apparently *early* tanks had baffles, and there are some indications that later tanks both did and did not, possibly down to the manufacturer and supplier to Abingdon. I would have thought that for road use it would be necessary on the early cars with the fast-acting fuel gauges, less so from mid-65 with the slow-acting gauges.

Welding petrol tanks is a minefield (i.e. BOOM!). Fill it with sand (as used by Desert Rats).

But it has got to be some corner if you are holding the fuel away from the pickup long enough to empty the float bowls - unless you are using injection. Maybe your fuel pump just isn't up to the job and is resulting in low fuel level in the float bowls, which a corner then worsens to no fuel at all.

Paul Hunt 2

Could you fit a separate reservoir, akin to an EFI swirl pot, somewhere in the fuel line to save chopping up the tank?
Steve Postins

Mark - Drop some dry ice in the tank (a large enough amount to last long enough for the hot work) and give it a few minutes to displace the fumes with CO2. This will inert the tank, making it safe to work on. Good luck - Dave
David DuBois

"... a separate reservoir ..." a huge float chamber, I like it. Without a float you would need a bleed valve on top when you first filled the system otherwise you would only get a bit of fuel in the bottom, and G-forces would slosh that away from a pickup as well. You would also need to bleed it periodically as it will almost certainly gradually fill up with air from bubbles from the pump. *With* a float you would need an open vent at the top just like a conventional float chamber. Even then the chamber would need to be deeper than it was wide, and ideally tapering to the bottom, or you will get the same slosh effects. How much fuel do you use on a typical event? If only a couple of gallons and you don't want to lug a full tank around (which is another way of preventing surge away from the pickup) then switch over to a smaller tank which *is* full. All rather a lot of pfaff for an occasional track-day.
Paul Hunt 2

This thread was discussed between 31/03/2006 and 02/04/2006

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