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MG MGB Technical - Petrol vapors in boot Picture included

1972 MGB
Just re sprayed the inside of the boot, and in doing so decided to take the emission pipes off to make cleaning and spraying the floor easier. the pipe that goes through the floor to the right of the fabric fuel pipe, didn't want to undo, so i left it. But unbenounced to me i had fractured the pipe or braded hose, and now i get a strong smell of petrol and some spollage onto the floor if i fill the tank more than half way. I still have the carbon canister up front, with everything connected and a vented rocker box cover, oh and the petrol cap is not vented.
Can i eliminate all the emission stuff in the boot ?
How can i stop the smell ?
This areea of the emissions/fuel system doesn't seem to be listed in the Moss catalogue.

Ideas and thoughts greatly appreciated.



Gerry Lodge

Why don't you just put right what you did wrong and not be a DPO? If you remove the separation tank and hoses you will have to seal the ports on the tank and the charcoal canister, and fit a vented filler cap.
PaulH Solihull

Gerry-
I have to agree with Paul. Restore the system. If you eliminate the vapor separator system and plug the charcoal cannister, the inside of your garage will reek of gasoline as it evaporates out of the fuel tank and out through an unvented gas cap! Just take the damaged hose and fitting to a shop and get it reproduced with new stuff.
Stephen Strange

I broke the fitting that joins the pipe to the hose. It is not in any of the parts catalogs. Welding instructor at the Technical Centre of the High School welded it for me as a demonstration to our adult welding class. Made it look so easy it was embarassing. I was woried about filling the hole.
Kelvin Hawkins

Now I have a 1972 GT there are no charcoal canisters etc I don't have a smell, all fine, but there is a vent pipe. is this part of the tank, or is it the axle vent hole? I am told, don't seal axle vents as pressure can build up and blow seals as all the parts warm up. Indeed when storing axles don't allow them to draw moisture into their chamber otherwise they may rust up inside.Does not happen to a working axle. Mike
J.M. Doust

All MGBs had a vented axle but this is just a screw-in plastic widget on top of the axle tube to the right of the diff, so unless someone has piped that off the axle for some reason it won't be that. The vent should be fitted because it has a convoluted and restricted air flow path that stops water getting in. No vent i.e. an open hole is quite likely to let water in. It probably won't let two surfaces that are rolling or rubbing against each other rust, but it doesn't take long for surface rusting to form, witness brake discs when a car is hosed then left overnight.

fuel pumps also had two vents going into the boot on chrome bumper cars (one on rubber), ending in Tees, but these should not vent fumes unless the pump is faulty, they only equalise the internal pressure much like the axle vent.

An American spec 72 would originally have had a vented tank, so unless the tank was replaced by a non-vented when the emissions stuff was removed there will still be a port or pipe somewhere, which may have been sealed, in which case a vented fuel filler cap should be fitted.
PaulH Solihull

My carbon canister leaks gas out the bottom vent hose. I don't think this should happen. If I replace the canister will it stop?
Cbrjr Carl rhue

No, it is your carb float valve(s) that is/are leaking. Either the valves have worn and won't seal, or there is debris from dirty fuel affecting them, or you have a non-standard pump putting out too much pressure which is overwhelming them.
PaulH Solihull

If it is the fuel pump, do I put a regulator on it or what.
Cbrjr Carl rhue

It has a few times drained the fuel tank
Cbrjr Carl rhue

You can put a regulator on it, it needs to restrict the pressure to about 2-3psi.
PaulH Solihull

This thread was discussed between 10/12/2011 and 31/12/2011

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