[TR] Anti-run on valve TR6

[Dave1massey at cs.com]

In a message dated 12/28/2008 11:17:48 AM Central Standard Time, 
mondoluxe at suddenlink.net writes: 
> ---- Has anyone on the list ditched their anti-run on valve?
> 
> I've always been puzzled by it's existence because it seems to me 
> that it's very existence indicates that it was engineered in a 
> band-aid solution to a more serious problem, ie: a poorly designed 
> gumment mandated attempt at reducing emissions.


Quite the opposite.  I retrofitted one onto my 71 TR6.  Calling this a 
pollution control device is a bit of a stretch.  It is what its name implies, a 
device to reduce running-on when switching off the motor.  It works by applying 
manifold vacuum to the charcoal canister.  The charcoal canister is connected, 
via tubes, to special ports on the carburetors leading to the top side of the 
float chambers.  The vacuum applied to the float chambers will pull the fuel 
away from the jets starving the A/F mixture to prevent run-on.

Of course they introduced it at the same time as they dropped the compression 
ratio.  That means they were not fitted to the early cars which needed them 
the most.

On the other hand, if you have already removed your charcoal canister you may 
as well remove this valve since it is ineffective without the canister.

Dave