Re: The Duchess Project: 1940 Super 8 Convertible Sedan

Posted by Joe Santana On 2013/5/14 11:45:54

Thanks, JW, for the ifo and encouragement.

I re-read my comments. You'd need a doctorate in hieroglyphics or Google's computer program that asks "Did you mean...?" to understand what I wrote. I need to edit my comments before posting.

What I was saying was that I wondered if the vacuum advance might not be working, causing the fluffing problem when the engine is hot and under stress...like a hill...when the accelerator is depressed.

There were 3 places that could cause the distributor spark advance (not advantage) not to work:

1. Little or no vacuum from the base of the carburetor, where the distributor vacuum advance is connected now. (The result of that test is the movie I posted, which I'm not sure anyone can view, but it shows, as you described, no vacuum at idle, and up to 20 in.Hg with a little depressing of the accelerator. That works. If I didn't get much vacuum, I would have switched the tube to connect at the rear exhaust manifold. I may still do that, based on your recommendation re the overheating at idle on a hot day. But I also understand that the timing would have to be adjusted because some vacuum would be present at idle when connected to the manifold.)

2. The vacuum advance diaphragm is split. If the lever (not level) ,the arm, does not move when vacuum is applied revving-up, then the diaphragm is torn.

3. The spring on the arm is broken. If the arm moves, but doesn't retract, then the spring is weak, broken, disconnected.

How does one person test the movement of the diaphragm or the arm? If I take the distributor cap off to look in there, the car won't run.

Setting the floats accurately I didn't get to it last night, but will tonight.