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TR2/3/3A green heater knob - TR3A

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NutmegCT

NutmegCT

Great Pumpkin
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I'm replacing my stuck (and incorrect) heater valve with a Moss replacement.

Valve is in, but the green knob at the top seems a tad "flimsy". There's a rubber (?) fitting down in the valve, so there's a bit of play back and forth when I turn the green knob.

The valve is also stiff, so I'm actually reluctant to turn that green knob, for fear of breaking it. I vaguely recall some posts here many moons ago mentioning the green knob's weakness.

Are the symptoms I'm experiencing to be expected? Or did I just happen to get a "shoulda been" factory reject?

Thanks.
Tom
 
Sounds exactly "as original" to me, except for the rubber fitting in the valve. The original knobs were very flimsy and easy to break, which is why there are so few originals left in the world.

You can likely loosen up the valve by disassembling it, and replacing the packing with PTFE or graphite packing. I'd also coat the threads with dry moly or similar. Then tighten the gland nut only the least amount required to stop weeping. Also don't close it too firmly.
 
I leave my heater valve open all year long. When it's 100 deg. F in the summer, it sometimes comes in handy to turn on the heater to cool down the engine a bit. But Louise doesn't appreciate that !!!

I think I've turned off the green knob on the heater valve twice in 17 summers of driving. That was to get a bit of cool air on our legs with the front vent flat open. If fact, come to think about it, I've only had the vent flap up twice in 17 summers too.
 
I ordered the TRF valve a couple years ago, and was twisting it just for fun last weekend; like butter, I tell ya! Really, I was surprised how simple the action was....
 
My valve is medium easy/hard to turn. You can tighten down on the hex at the top of the body to tighten it as you like. I bought a new one 17 years ago to replace the original. Here is one last year when we put it on a late TR3A. The hex is down the valve stem at the top of the body.
 

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I slightly loosened the packing nut, and also lubed the threads a bit. Turns much more easily - thanks for the suggestions.

Also added those missing float bowl vent pipes. Today I'll continue rubbing down the exterior paint.

Thanks all.
Tom
 
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