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5K Engine Starter issue


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Oh I see!  That is a lot in that case.

Do you crank it with the accelerator open, or crank it with your foot off?  I see people start a car with their foot off the pedal, which gives it max vacuum advance, although I start a car with maybe 20% gas so at cranking speed there is virtually no vacuum & no vacuum advance. 

I did a lot of work with vacuum advance and springs when I fitted an electronic dizzy, they are hopeless for advance as they're made for 5K forklifts. Eventually I found the right springs to give low advance at idle and a fast curve up to 35deg at 3000rpm. I marked the pulley with 'liquid paper' or some similar typing correction liquid so I could measure out to 50deg.

Your manifold vac gives max advance at idle & over-run, and a large advance at cruise, and no advance under acceleration. Other carb manufacturers use a port advance which gives no advance at idle and max at high rpm, so there are options out there. The vacuum advance is for pollution control, to get a better burn and cut nitrous oxide emissions in lean conditions, you can disconnect it and just run on the weights in the dizzy.

That's worth a try, plug the hose with a nail and set the timing to 10deg at idle, and see how it drives. It will be cranking against only that 10deg then, a much easier job.

Most of the dizzy work is here-


Crank pulley.jpg

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So it seems disconnecting the vacuum advance helped a lot. 

Today I went to the gas station I mentioned and the car started with no issues there. Didn't notice any loss in performance by running it with no vac advance.

I also charged the battery for about 4h before going which might have helped

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