Check out this Technical Service Bulletin.
Very cool find! Thanks! So from that, what he has is a factory hot idle compensator PORT and not a valve.Check out this Technical Service Bulletin.
Ok. That mystery is now finally solved. I have been reading those TSBs but never the 1973 part.Check out this Technical Service Bulletin.
That's why a thought that it was added later. I never knew that hic-PORTs without a valve even existed. Since thisTQ obviously is remanufactured it's not sure that the parts were originally together. Now I know how to deal with it.If it had the valve, it would have the two threaded mounting holes, as seen in post #48.
TQ with HIC. There is a hole of about 7/32" under the HIC, goes through to the carb base. When I am going to use a TQ on an engine with a big cam, I use that hole for bypass air. I make a plate that screws into the adjacent boss that I can swivel over the hole to vary the amount of air.
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