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Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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#66323 09/24/2006 6:48 PM | Joined: Jul 2006 Posts: 186 'Bolter | | 'Bolter Joined: Jul 2006 Posts: 186 | Hey guys, I am trying to replace my vacuum advance and I don't know where to buy one with the correct angle on it. I bought one from Classic Chevy parts (Chevy Duty) and it isn't right even though the catalog says its for a 49-54 chevy. Their tech support said I could bend the vacuum line and make it work but the problem is with the hold down bolt and the distributor clamp screw which are interfering with each other. I have some digital pics I took to show the comparison but don't know where to put them so you an see them. I can send them to you if you supply your e-mail address. Thanks for any help.
Still trying to get ole Betsy back on the road.
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#66324 09/24/2006 7:37 PM | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Craig, Jim Carter and Obsolete Chevrolet and others do sell the correct vacuum advance mechanism for a truck. I got a correct one from both Jim Carter (after 6 months) and Obsolete Chevrolet (on week) last summer. The angles on the automobile advance mechanism are, just as you describe, incorrect and will not bolt-on properly/easily (on a truck). Here is the truck vacuum advance. Here is Chevy Duty's photo of the truck mechanism. I will try to find a photo of the automobile vacuum advance. Tim | | |
#66325 09/24/2006 9:31 PM | Joined: Jul 2006 Posts: 186 'Bolter | | 'Bolter Joined: Jul 2006 Posts: 186 | Hi Tim., Thanks for the information. I responded to the e-mail notification that was sent to me by the forum but I guess it didn't post back to the forum. I note the pictures that you listed are just like the part I got from Chevy Duty that was the wrong item. I sent you some photos via your e-mail as I didn't know how to get them to the forum. One photo shows the difference in the bracket angles of the two different vacuum advances. I looked at both Carters and Obsolete and some other catalogs I have and they all use the same photo which looks to be the wrong one. If you know what part number is correct for either company I will order from them. Thanks again
Craig
Still trying to get ole Betsy back on the road.
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#66326 09/25/2006 12:01 AM | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Added from email photos sent by Craig: Craig\'s original vacuum advance Craig\'s vacuum advance and a truck vacuum advance Craig, You vacuum advance mechanism is off an automobile engine. If you vacuum line was already plumbed for attachment to the automobile vacuum advance, you might as well get an automobile vacuum advance mechanism. I think that I found one at Harmon's and maybe at the Filling Station and at a few other sites (they had photos that could not be copied). If you cannot find one, post a reply here and I will look for a source. Classic Parts of America (Chevy Duty) will most likely take the part back (but you might have to pay return shipping). Tim | | |
#66327 09/25/2006 12:17 AM | Joined: Jul 2006 Posts: 186 'Bolter | | 'Bolter Joined: Jul 2006 Posts: 186 | Tim, more great information. Just my luck to have a car vacuum advance distributor in my engines - yes - I have two, both from trucks and the same type advance mechanism!. Question - is the distributor clamp different for a car and truck. I wonder if I had a truck distributor clamp then the vacuum advance bracket for the distributor would not interfer with the octane selector(vacuum advance) bracket. But, like you suggest it might be easier to find the car vacuum advance than a distributor clamp. I'll see what I can find. Thanks a million!
Craig
Still trying to get ole Betsy back on the road.
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#66328 09/25/2006 12:19 AM | Joined: Jul 2006 Posts: 186 'Bolter | | 'Bolter Joined: Jul 2006 Posts: 186 | Tim, more great information. Just my luck to have a car vacuum advance distributor in my engines - yes - I have two, both from trucks and the same type advance mechanism!. Question - is the distributor clamp different for a car and truck. I wonder if I had a truck distributor clamp then the vacuum advance bracket for the distributor would not interfer with the octane selector(vacuum advance) bracket. But, like you suggest it might be easier to find the car vacuum advance than a distributor clamp. I'll see what I can find. Thanks a million!
Craig
Still trying to get ole Betsy back on the road.
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#66329 09/25/2006 1:03 AM | Joined: Jul 2006 Posts: 186 'Bolter | | 'Bolter Joined: Jul 2006 Posts: 186 | Tim, Problem solved! I ordered the correct one (the picture looks like my original)from the Filling Station... I can't thank you enough. It might seem simple to some but this thing has bugged me for almost two months. Thanks to you and Stovebolt for being there for us truckers.
Still trying to get ole Betsy back on the road.
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#66330 09/26/2006 1:18 PM | Joined: Jul 2006 Posts: 186 'Bolter | | 'Bolter Joined: Jul 2006 Posts: 186 | Tim, one more item. Any idea where I can get an original distributor clamp for the truck engine? Then I could use the other vacuum advance I ordered on my second engine and it would be original.
Thanks again
Still trying to get ole Betsy back on the road.
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#66331 09/26/2006 4:40 PM | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Craig,
I have never seen that piece by itself for sale new/repo.
Maybe a "Want Ad" in the Swap Meet section will find you one.
Tim | | |
#66332 09/26/2006 5:48 PM | Joined: Jul 2006 Posts: 186 'Bolter | | 'Bolter Joined: Jul 2006 Posts: 186 | Okay, I'm off to the swap meet...
Still trying to get ole Betsy back on the road.
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