Thanks for the input, and sorry for posting in the wrong place. I did search for past posts on this subject to no avail.
I have a new heat riser on order, but it can't be diverting the exhaust through the intake if it is totally missing the butterfly. It only diverts when partially or fully closed.
The starter cranks over just as quickly when at running temp.
The float valve opens when the bowl boils over and replentishes the fuel until residual pressure is relieved in the line between the fuel pump and the carb. This floods the engine, thus the hard start when at running temp. At least this is what I believe is causing the symptom. Just trying to get to the cause.
I can't figure out why the intake gets so intensely hot at the bypass. I fully expected the butterfly to be stuck in a closed position, not entirely missing. The paint burned off that area long ago, and maybe that's normal. I built the engine so many years ago, but maybe I left out a restricter plate in the intake, or maybe it eroded over time. Since this issue only reared it's ugly head in the last few years.
Thanks again for the suggestions.
Last edited by KD Kibbe; 10/26/2010 6:09 PM.
