292 Questions

[May70]

Originally Posted by Steeveedee

Are you absolutely certain that the heat riser valve is open, hot? You can verify that by poking the counterweight with something, since it will be hot. I believe you replaced the exhaust manifold, so the heat riser valve is new? Didn't want to read through it all again, sorry.

Yes the whole exhaust manifold is new. The only thing not new on it is the carb auto choke spring assembly.

Just to be certain im thinking of the same thing, the heat riser is on the bottom side of the exhaust manifold and it has a plate inside that either opens to allow heat up to the bottom of the intake manifold or 'closes' directing heat away. Is this what you refer to as a valve?

If so the counterweight is not stuck, I can move it with the engine hot or cold I just have to oppose the little heat spring. However I have not seen it get hot enough to release the heat spring letting the weight fall down (closing the plate). I have only seen the weight up so it should be open.