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Gas fumes?

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TR4

TR4

Jedi Knight
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Is there suppose to be a sealing gasket on the bottom side of the flip lid on a TR4 gas cap? I am getting a lot of fumes in the garage and that is one point I can definitely smell fuel. I have a new replacement cap and there is no sealing gasket that I can see. Is the seal supposed to be metal to metal? There is a hard rubber gasket around the filling tube but it is below the top edge of the tube so that won't keep fumes in. Any advice or tricks to help would be appreciated.
 
That's got to be the same as a Spitfire. Yes, there is a round rubber gas cap gasket that fits over the inside of the lid. Check Ebay, they are about $7.00 new.
 
I am away form the car at the moment but my recollection is that the sealing gasket for the lid is in a groove in the lower portion... i.e. the rim of the cap fits tightly against this gasket when the cap is locked down.

If missing or deteriorated the gasket can be easily replaced, it is sort of a square O-ring -- I think I have used an uneeded oil filter gasket cut to length and jammed in there.

There are more likely sources foe those fumes... some of which may seem to be emanating from that spot: deteriorated filler hose, overflow on the tank are two suspects.

Are you by chance topping up the tank until the pump nozzle shuts of automatically? You might try keeping the tank below 3/4 full. When really full I think a hard right turn with a very full tank may push gas out the overflow/vent.
 
I was told that if you fill the tank too high, or if it sloshes on fast curves, the ethanol added to gas these days will eat away this gasket.
 
I was told that if you fill the tank too high, or if it sloshes on fast curves, the ethanol added to gas these days will eat away this gasket. My TR3A has a drain olug on the bottom of the tank and just a few days ago, it had a drop of gas on it about every 5 minutes which would drip onto my garage floor. Does the TR4 have a drain plug ? If so, check it and tighten the plug. That's what I did and the smell has gone.
 
Geo Hahn said:
If missing or deteriorated the gasket can be easily replaced, it is sort of a square O-ring -- I think I have used an uneeded oil filter gasket cut to length and jammed in there.
Click to expand...

I'll try adding the oil filter O-ring to see if that helps and also check the drain plug and overflow tube. Thanks, Phil
 
I am having problems with my fuel pump and the rebuild kits for it. The problems seems to be related to ethanol gas by all indications. See my thread on this for other peoples comments.
 
You might also check the seal on the bottom of each carb. That was the source of the leak on TR3. Just enough seepage to dampen the choke linkage, but not enough to "puddle up" anywhere.
 
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