Distributor vacume advance

Bob Snow

New member
Need help in finding a source for a distributor vacuum advance for my 1971 Dauntless V6. I was told by PO that it was a Buick 3800 Engine. Once I found the casting number, etc. it showed up as a Jeep engine and if I calculated correctly it is a 1971 model. Casting Number on block back by the bell housing is 991503, casting number on intake is 1378704-E and the pressed number on the crankcase by the right hand side exhaust ports is something TH something 10. From what I have read the T signifies that the engine was built by Jeep in 1971. Have this engine in a 1952 Willys M38, CJ3.

Anyway does anyone know of a source for a vacuum advance for this engine? Apparently the diaphram is torn or rotten. Doesn't move a lick under acceleration.

Thanks for your help.
 

Hey Bob,
You probebly have a nipple at the base of the carb (not sure which carb you have?). Regardless, you can tap into a ported source meaning its the vaccum regulated by the throttle plates (this would be a port right at the base of the carb. If you have a pre-emissions set-up (which I believe you do) you can use manifold vaccum which is any source on the manifold which is tapped directly into the plenum. Be advised that some carbs do not work well on manifold vaccum and vise versa.

A quick photo or two of your engine set up would help.
 
J C Whitney has a universal vacuum advance for distributors. Does anyone have any experience with this product? It is made by Taylor.
 
Manifold vac will be at the base of the carb(throttle plate), ported will be above the throttle plate. Prestolite or Delco dist?? If you have the Prestolite, I do not think the vac advance is replaceable, or too expensive to mess with, cant remember which. Most advise switching to the Delco points dist, think you can get one at your local auto store for around 50.00. If you already have the Delco you should be able to get the advance unit at any auto store. Can you post a pic of the dist and I could tell you if its Prestolite or Delco. The universal (adjustable) cans are great, but you have to set the right amount of advance on it or the engine will ping from excessive advance or be a turd from not enough. The dauntless v6 also could be a odd or even fire engine, need to no which if you swap dists. shouldn't matter with just replacing the can (delco). The 71 Dauntless v6 "should" be a Odd Fire and "should" have the Prestolite.
 
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That looks like the prestolite dist. The bad news is there are very few part available if any for it, I even went on another forum for help and nota. Everyone suggests replacing it with the delco points dist or just replacing your whole existing dist. They said you will not find a advance unit for it. Oh, and that is a odd fire engine.
 
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69jeepcj, Could I trouble you to look at an item on e-bay. Looking under electronic ignition I found a Pertronics, delco points dist 1162A, Ignitor module 6 cycl. $69.95
Under compatible vehicle it shows a 1971 Jeep CJ5 with the 225 V6 engine. Is this what I would need to convert to an electronic ignition?
 
If I seen it right, that is the petronix unit for the 225, but with the delco dist, it will not work with your prestolite. This would be a odd fire delco points dist that you would need. 66-68 single poinst odd fire dist for the buick dauntless v6 1110376, then If you want you can use the petronix. you could also swap to a HEI dist (electronic ignition) out of a 75-76 buick skylark, same oddfire engine, but you would have to grind some of the manifold to make it fit and don't know if you want to go through all of that
 
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I have found a source that rebuilds vacuum advances. So will be sending mine off for a rebuild. Thanks to all that have responded.
 

Let me know how the rebuild turns out if you would. thx
 
In the picture, you have pretty bad corrosion where the condenser connects to the main wire.
If you are going to use it, You may want to pull that apart and clean it.
Good luck.
 
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