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NutmegCT

NutmegCT

Great Pumpkin
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When I first got TeeYah I wondered what this was. See pic below. Do we notice anything ... unusual ... about this lonely little device?

Today I found out what it's supposed to do (note emphasis on *supposed*) when I removed the fuel pump bowl to empty the sediment.

Can we say "gusher"? Can we say "free flowing unblocked fuel line"? Can we say "well-soaked floor, fuel running out the door"?

Pardon me while I empty a couple gallons of fuel from my sneakers.

Oy.
 
Yes, they are usually removed or bypassed as they were so prone to leaking. A great idea, though, if they do work.
 
When my Tr-3 was "on the road" I frequently used that shut off valve when the car was parked and un attended to help prevent theft. I always thought that it what it was for sence I never had to change my fuel pump.
 
Leaks are easy to fix, though, just replace the cork seal inside the valve. They shrink over time, beyond what can be compensated for by tightening the clamp.

Many years ago I couldn't find a suitable cork seal, so I fabricated one from fuel line. Since then it's started to drip only once, and promptly quit when I put another 1/4 turn on the clamp. The fuel line is a lot 'grabbier' though, so it's a fine balance between sealing and being so tight you can't move the valve.
 
We all know the core or seal of the valve is made of cork and cork comes from the bark of cork trees. Natural vegetable things like cork have veins in them and the veins can allow the gas to leak. So I made a sustitute fron a piece of gas-line rubber hose about 12 years ago with the center bit filled with cork to fill the center. Maybe you got the idea from me Randall ? Anyway, last year I couldn't turn off my petrol stop-cock - it was so tight - so I got to thinking about modern synthetic substitutes for the natural cork seal or bung. Now they have synthetic "corks" in many wine bottles and I thought if it can stand up to wine, maybe it'll be good for the seal in the gas shut-off valve. So I cut up half of a "cork" and soaked it in gasoline over the winter. There was no reaction.

So I made a seal or bung out of the other half of this synthetic "cork" and it worked fine. A few 100 miles later, I was no longer in Canada, but I was in upper NY state on my way to VTR when I filled up with Mobil 92 octane. After about 3 tankfuls, I was at VTR and my friend Jeff Kramer in his dark blue TR4 who was following me noticed that I was leaking gas. So we stopped and the stop-cock was leaking all over the road. I pulled out the knob on the top and all the synthetic "cork" had disappeared. I quickly pushed in the temporary plug I had made about 5 years ago (just in case) and the leak was "fixed". But where was the "cork" material made of the synthetic "cork" ?

I can only guess that it was the ethanol in US gas that we don't have in Canada that ate the synthetic "cork" or dissolved it. The bits must have flowed up into the float bowls and the carbs to be burned with the gasoline in the engine. The bottom of the float bowls were clean.

I re-built my valve at VTR with a real cork that I carry with me and it is working fine. This way, I didn't lose any concours points for having a temporary plug in the body of the valve.

Now you know the rest of the story !
 
Don Elliott said:
Maybe you got the idea from me Randall ?
Click to expand...
Don't think so ... mine was before we moved to this house, which was in 89.
Don Elliott said:
I can only guess that it was the ethanol in US gas that we don't have in Canada that ate the synthetic "cork" or dissolved it.
Click to expand...
Not just ethanol, IMO. They've been putting all sorts of other nasty stuff in our gasoline (at least here in Kalifornia) for many years, and it does tend to just dissolve some old fuel components. Turned the diaphragm in the electric fuel pump for my generator set into rather sticky jelly; and dissolved the 'rubber' on a NORS TR3 fuel pump diaphragm in a matter of days. The fabric was intact, but you could see through the weave all around.

At that time we were getting MTBE instead of ethanol as oxygenate; but it might well have been one of the other various additives like benzene.
 
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