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Do I need it?

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AltaKnight

AltaKnight

Jedi Knight
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There's a little doohickey on the TR6 ZS carbs; I think it's called the "Float Chamber Vent lever", it seems to be actuated by the throttle and pushes on a rod when the carb butterflys close. I think somehow it closes off the vent when at idle though I can't imagine why you would want to close the vent.
Anyway, one of mine is binding and stops the throttle plates from closing properly leading to an unpredictable idle speed, so I took it off and the car idles perfectly now; do I need this thing on there and why?
 
Nah, you don't really need it. Without it, the anti-runon solenoid won't do it's job (but most people have them disconnected anyway). Also your car may emit more hydrocarbons when you shut it off. But it won't affect how it runs.

With the valve closed, the float bowls are only vented through the carbon canister. It's open for normal running, to vent the float bowls to the air intake (to ensure the pressure in the bowl is exactly the same as the intake, since any difference in pressure will upset fuel metering).

OTOH, most likely it only needs a bit of cleaning to free it up.

BTW, I believe 73 was the first year that had the bowl vent valve (and the anti-runon solenoid).
 
Thanks Randall
 
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