Yes, I agree it can be confusing & now I'm confused.
Quoted from the repair manual...
"valve may stick in either the "heat on" or "heat off" position.
"If it sticks in the "heat on" position,
it will result in poor engine performance, overheating and detonation."
"On the other hand, if it should stick in the "heat off" position,
the heat will be turned off the intake heat riser at all times and result in poor performance,
particularly while the engine is warming up and driving at lower speeds."
To me, "heat off"(as quoted from the manual) is the same as removing the flapper completely.
And If you remove the flapper, the flow is now open and the hot gases go out the tail pipe.
Am I understanding this correctly?????
Nope, sorry to say. "Heat off" means the flapper is redirecting the flow away from intake and down the pipe. I think you got that OK. Removing the flapper (which I sort of said off handed "faghedaboudit", has a consensus here of no-no) will allow the "so called heat" to heat up the intake on it's way out even though the passage down tail pipe is fully open also. That is much closer to "heat on". Some heat (XX%) will swirl, flow against and around the carb base mass on it's way out. Putting "heat on" it.
So now I'm acting like Mr. expert riser man.....not. Many on the web say it's OK without the flapper. Yo, I gotta stick with my Stovebolt boys and say leave it in....and do what I want on my motors.
