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MG MGB Technical - FUEL TANK REPLACEMENT

It's time to replace the fuel tank in my USA spec. 79 MGB. All the parts have arrived and seen to be complete.

Fuel tank
Hardware kit
O-ring - filler neck
Fuel Level sending unit
Gasket for sending unit
Seal ring - sending unit
Packing strip for tank top

Is there anything, procedurally, I should watch for.
I see a threaded fitting on the top of the tank for the emissions canister mounted inside the trunk.

Is that fitting attached to a rubber hose or is it a solid piping??

Should I coat the tank prior to install and if so what?

Any pit falls in the process of remove/replace?

Any thoughts

Cheers

Gary
79 MGB
gary hansen

"Should I coat the tank prior to install and if so what?"

I made sure my tank had a few coats of Bondaprimer and paint, followed by Waxoyl on the top, which is where it will rust.
Dave O'Neill 2

x2
Max71

Gary,
Is it a painted tank or one of the Canadian plated ones. If plated, check the quality of the soldered connections they are sometimes a bit "iffy". The painted, plain steel tanks, have brazed attachments which are much stronger, paint as normal and as Dave said, Waxoyle the top. I also seal the leading "lip" of the tank to the boot floor, as that's where the water, salt and muck get to the top of the tank. (Sorry forgot you are in Florida and heat is your main weather problem!!!)
Plated tanks will need degreasing and a light coat of etch primer before a coat of black.
Allan Reeling

Allan.Yes the tank is Canadian. A John Twist You Tube item had some comment about the soldering of the threaded emissions fitting. I will discuss this with the fellow who is going to help me with the replacement. Surely there must be a way to test the tank for leakage

Cheers

Gary
79 MGB
gary hansen

Gary,
I've had 2 of the plated tanks with leaks from the fuel outlet union. One was there from day one, the other developed very quickly. The earlier B's had a solid outlet pipe to the pump. One thing I did was cut this and introduce a piece of rubber hose to prevent vibrations from stressing the joint. When I got the 3rd tank I re-soldered the joint before installation. That, together with the rubber hose, seems to have prevented a reoccurrence.
Allan Reeling

Allan. I will check the soldered threaded joint on the tank and will resolder it. The soldering does not look too "professional" which is why I post to get wise advise, Thank you for that.

Cheers

Gary
79 MGB
gary hansen

Gary, I'd like to add one thought: I don't think any of the current repro tanks come with a drain plug. When I restored my '73 BGT (bare metal body, gutted interior etc) I applied POR 15 epoxy fuel tank sealant to the inside and did what others above said for the outside. I then had my local radiator guy let in a drain plug with a flush-fitting allen-head plug. Best thing I ever did - lets me drain periodically with no fuss at all - worth considering.
Yours, John.
J P Hall

This thread was discussed between 18/08/2017 and 22/08/2017

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