The Ford Barn

Hivolt5.0 · 01-07-2013, 10:25 PM

I'm curious where you all get a vacuum advance for a 312. The one off my distributor has a straight shaft (see pic) but all of the replacement ones have a bent shaft.

The engine hasn't been running the best lately. It idles fine and drives ok but as you are cruising you can feel some hesitation/surging or perhaps a bit of a miss. I recently installed a MSD chrome coil but still have the points. I asked, before I did this if it'd be ok and the consensus was as long as I had the ballast resistor it should be ok, which I do. With the miss/hesitation I thought perhaps the coil was burning my points so I switched back to the old coil but before I took it for a spin I decided to check the points and vacuum advance. The points looked great, no burn spots, but when I put my vacuum pump on the advance I couldn't pull any vacuum. I'm assuming a faulty vacuum advance would cause the hesitation/surging/missing feeling the motor has.

What else should I check???

thanks
David

franksford · 01-08-2013, 02:57 PM

Sponsored Links (Register now to hide all advertisements)

I'm looking at your advance and the vacuum line adaptor is not showing any threads??? that would be wrong. for a 57 312. I think i may be able to help. call (616) 874-1224 Frank

01-07-2013, 10:25 PM	#1
Hivolt5.0 Senior Member Join Date: Jun 2010 Location: Ft. Walton Beach, FL Posts: 136	vacuum advance on 312 I'm curious where you all get a vacuum advance for a 312. The one off my distributor has a straight shaft (see pic) but all of the replacement ones have a bent shaft. The engine hasn't been running the best lately. It idles fine and drives ok but as you are cruising you can feel some hesitation/surging or perhaps a bit of a miss. I recently installed a MSD chrome coil but still have the points. I asked, before I did this if it'd be ok and the consensus was as long as I had the ballast resistor it should be ok, which I do. With the miss/hesitation I thought perhaps the coil was burning my points so I switched back to the old coil but before I took it for a spin I decided to check the points and vacuum advance. The points looked great, no burn spots, but when I put my vacuum pump on the advance I couldn't pull any vacuum. I'm assuming a faulty vacuum advance would cause the hesitation/surging/missing feeling the motor has. What else should I check??? thanks David Last edited by Hivolt5.0; 01-09-2013 at 09:14 AM.

01-08-2013, 02:57 PM	#2
franksford Senior Member Join Date: May 2010 Location: Rockford Michigan Posts: 190	Re: vacuum advance on 312 Sponsored Links (Register now to hide all advertisements) I'm looking at your advance and the vacuum line adaptor is not showing any threads??? that would be wrong. for a 57 312. I think i may be able to help. call (616) 874-1224 Frank