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MG MGB Technical - Fuel smell???

Noticed a strong smell of fuel both in the garage at home and when I drive the B. My friends said they could smell fuel/exhaust on my clothes when I arrived for a lunch the other day.
I have spent all day looking for leaks etc....but to no avail. Noticed the tank has a repair near the seal/ring/sender unit, but doesnt appear to be leaking.
The car is tuned well and running beautifully....nice grey coloured exhaust pipe. I dont know where its coming from. It has no pollution gear and the exhaust has no leaks.
Just been for a drive again and can smell it on my shirt.
Any suggestions from you gurus?
MF Cody

Two thoughts. Switch on but don't start the engine and listen to the fuel pump. It will fill the carbs then should stop ticking. Leave it switched on 5 mins and see if it ticks when it shouldn't - indicating a leak after the pump. If that's OK it puts you back with the tank. Tanks can rust through on their top surface, under the boot floor where moisture gets trapped. Unless they are really full they may not leak but the vapour will greet you when you open the garage. The filler connections and seals are also worth a look. Rich.

Rich

If its a newer model(70-80) check the hoses and fittings for the vapor recovery can in the trunk.

Had the fuel smell problem with mine and all the hoses in the trunk were hard and cracked.
William Bourne

The times I've smelled fuel, it's been problems with the fuel lines near the carbs or the silly little rubber grommets on the plastic fuel lines where they enter the float chamber. Not sure what carb(s) you have though. Lift the hood after you start the car and feel around there, looking for leaking fuel. Best to make sure it's not leaking around there, as raw fuel is not a good thing around a hot exhaust manifold.

Roger
'69 Roadster
Roger Hotelling

I would like to replace the hoses to the vapour recovery can in my 1971 mgb. Moss lists these as Not Available. Where can they be purchased new? Are these standard braided hoses that can be purchased at the local autoparts store? Thanks
Tim Mayor

MF Cody, as a matter of aerodynamics, its possible for the exhaust gasses to get back into the car (with the top down) while you're driving. I know when I'm tuneing my car half out of the garage, I smell like exhaust when I'm done too. Its the same smell you take on from riding snowmobile, and I always liked that!
Jeff Schlemmer

Thanks all.....
After much 'playing' about in the garage, I think there is a small leak from the top of the tank....somewhere! My dad, who borrowed the car to go to the shops (probably thrashed it, getting me back from my youth) failed to tell me that he had filled the car while he was out, up to the brim, that is till it overflowed out of the cap. The car was then parked on an angle (rear downhill) and it has subsequently leaked. I have now driven the car so its only got about half a tank of juice and hey presto, very little smell. So I can only make the assumption that it has a leak in the top of the tank....only evident when it is very full.
And Jeff from the States, yes its true....you do get an exhaust smell from tuning in the front yard!
I will look at the vapour hoses/fittings too....I'm not fully convinced I've found the problem yet. Nothing worse than fuel and hot exhaust etc.....MGB bbq!
Happy days guys.
MF Cody

Lately, I had a fuel smell that seemed to follow me after I drove the B for a while. Found a leak on the hose going to the bottom of the fuel filter on the firewall...very slow--only a drop or so a minute, but it was running down onto the throttle cable and then down to the pedal, where a bit would get on my shoes. Only takes a tiny bit of gas to make a lot of stink.
R. L Carleen

MF:

The tanks tend to corrode from the top down. Condensation in the tank tends to accumulate at the top and starts to rust if the car is left standing for too long. Crud, dirt, sand and rust tends to accumulate at the top between the tank and trunk floor further assisting the rust problem. In many cases they're just pinhole leaks but enough of them make a big problem.

Forget about repairing the tank if this is the case. Just dish out the cash for a new one. Make sure the new one has a plug or have one installed in the new tank.

Good Luck,
Luigi
Luigi

I began like you with identifying a leak on the top of the tank. Although there were no obvious holes, the areas under the rubber stips were rusty. When taking it out for replacement I found the rubber hoses hard and cracked and the metal lines corroded and brittle. In the end I replaced everything including the filler hose and the petrol pump.
Vic
V Todman

Have also heard of vapour recovery cans getting saturated with gas when the tank is filled to the top. If smell persists, check the charcoal inside.
Steve Rayment

This thread was discussed between 01/05/2005 and 06/05/2005

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