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Gromit · 01-10-2018, 05:52 PM

Looks like the Crane vacuum can is missing it's rubber sleeve bushing that goes over the tip of the actuator rod where it contacts the advance plate... that will take the 24 degrees that you mention down some - say .086 for example would be 8 crankshaft degrees advance - So in other words you end up with way too much without the bushing cushioning the stop.

You can use vacuum hose but it breaks down so you have to keep an eye on it.

Also that guy who used to be on this forum a lot who worked for Delco Remy in the 1960's on distributor design has a DIY with photos on how to fab a positive stop for the vacuum can pull rod so that you can run manifold vacuum without risk of too much advance... or alternatively Crane makes an adjustable plate too as you know.

Edit:

I just remembered the guy I mentioned his name is Dave Ray - I have some of his how-to photos but since I don't have rights to publish them I'd refer you to Mr. Ray if you want his input- he is very well known and should be easy to find.

01-10-2018, 05:52 PM	#31
Gromit Registered User Join Date: Jul 2015 Location: Central Coast, CA Posts: 498	Re: 71 350 running hot coolant backup up problem Looks like the Crane vacuum can is missing it's rubber sleeve bushing that goes over the tip of the actuator rod where it contacts the advance plate... that will take the 24 degrees that you mention down some - say .086 for example would be 8 crankshaft degrees advance - So in other words you end up with way too much without the bushing cushioning the stop. You can use vacuum hose but it breaks down so you have to keep an eye on it. Also that guy who used to be on this forum a lot who worked for Delco Remy in the 1960's on distributor design has a DIY with photos on how to fab a positive stop for the vacuum can pull rod so that you can run manifold vacuum without risk of too much advance... or alternatively Crane makes an adjustable plate too as you know. Edit: I just remembered the guy I mentioned his name is Dave Ray - I have some of his how-to photos but since I don't have rights to publish them I'd refer you to Mr. Ray if you want his input- he is very well known and should be easy to find. Last edited by Gromit; 01-10-2018 at 06:07 PM.