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#51458 10/24/2005 6:21 PM | Joined: Oct 2000 Posts: 244 'Bolter | | 'Bolter Joined: Oct 2000 Posts: 244 | Is there an easy way to test whether or not the vacuum advance is working properly on my 235??? | | |
#51459 10/24/2005 7:02 PM | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Buckaroo01,
I am a little reluctant to say the best way would be with a timing light. This would tell you if the entire system works. You could test the diaphram by sucking on it, plugging it with your tongue and feeling the vacuum. You could pull the vacuum line off the carburetor while the engine was running and listen for a change in RPM. You would have to plug the vacuum port in the carburetor while doing the procedure.
Stuart. | | |
#51460 10/24/2005 7:28 PM | Joined: Apr 2004 Posts: 703 Shop Shark | | Shop Shark Joined: Apr 2004 Posts: 703 | Buckaroo01,
On both, my 216 and 235, the distributor moves when I rev the engines.
I would assume, starting your engine, increasing the RPM's by hand, while watching the distributor for movement, would be the easiest way to determine whether or not the vacuum advance is working or not. | | |
#51461 10/24/2005 7:55 PM | Joined: Apr 2005 Posts: 42 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2005 Posts: 42 | Try engine running disconnect & plug vacuum line. use timing light to see timing marks & apply vacuum with a hand vacuum pump.
Another simple test would be to with engine at idle disconect & plug the vacuum source. Check base timing. Increase RPM to check mechanical advance. Re-install vacuum line & retest. vacuum advance will be equal to total advance minus mechanical advance. | | |
#51462 10/24/2005 11:05 PM | Joined: Oct 2001 Posts: 3,458 Extreme Gabster | | Extreme Gabster Joined: Oct 2001 Posts: 3,458 | At curb idle, about 600 rpm, the vacuum advance should not operate, it should be in the "relaxed" position just like with the engine off. As you open the throttle past idle, the advance should pull about 8.5 degrees of distributor rotation counterclockwise (17 degrees crank advance) . It should snap back as you let off to idle.
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A lone amateur built the Ark. A large group of professionals built the Titanic. | | |
#51463 10/25/2005 1:09 AM | Joined: Jul 2005 Posts: 226 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2005 Posts: 226 | you can also suck on the diagphram with a tube with your mouth and watch the plate the points are on to see if it moves..
What it will say on my Tombstone: "Boy, that guy sure owed alotta people Money"
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#51464 10/26/2005 2:51 PM | Joined: Oct 2000 Posts: 244 'Bolter | | 'Bolter Joined: Oct 2000 Posts: 244 | Once again thanks to all, I'll give it a test this weekend. | | |
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