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| | | | Joined: Sep 2010 Posts: 575 Shop Shark | | Shop Shark Joined: Sep 2010 Posts: 575 | I'm trouble shooting the typical 235 rochester B stumble...
I'm trying all the solutions I've been reading, float level, mixture, and more...
I haven't given up yet, but I want to know about vacuum advance. When I give a shot of gas, I observe the distributor twist quickly, and back.
If I hold the pedal down, should the distributor stay advanced until I let off the gas, or is it a pulse like I'm observing?
Mark | | | | | Joined: Feb 2004 Posts: 29,859 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,859 | The advance should pull opposite distributor rotation and stay there with a steady throttle. When you let off the gas, it will return to the retard position for idle. If it's moving CCW quickly and returning even with the RPM up, you've got a leaky vacuum advance diaphragm. Replace it.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Feb 2008 Posts: 212 'Bolter | | 'Bolter Joined: Feb 2008 Posts: 212 | I just installed a new vacuum advance unit on my distributor in the 58 apache. I was wondering about the same thing. Mine did nothing before I changed it, so now the distributor does a very sudden twist whenever I hit the gas.The tone of the engine is different also. | | | | | Joined: Sep 2010 Posts: 575 Shop Shark | | Shop Shark Joined: Sep 2010 Posts: 575 | The advance should pull opposite distributor rotation and stay there with a steady throttle. When you let off the gas, it will return to the retard position for idle. If it's moving CCW quickly and returning even with the RPM up, you've got a leaky vacuum advance diaphragm. Replace it.
Jerry Ya, it's returning right away. I'll swap it out, thanks Jerry. | | |
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