Vacuum advance for 48 dodge B1B

[Ron Day]

My vac. advance on distributor 1 AP 4101 1 (from 48 b1b) has bad diaphram and does not hold vacuum.  I have other Vac, Adv, units but this one is unique in that it has and off-set in the arm.   I have heard of prying them open and replacing diaphram but would want to make sure it is the final shot before distorting what may very well be not replaceable.   Is there a source for repair or replacement that may be available before I cobble up this one.   I am using this set up on my 49 dodge  because it was the only dist. for which electronic module was available at the time.   Incidently the changeover to Electronic module went very well, but leaves me with no Vac. Adv.      Thanks  Ron

Edited November 19, 2017 by Ron Day

[Don Coatney]

I believe Terrill machine in Texas can replace your rubber diaphragm.

[desoto1939]

Since you know the Vacum Advance unit number then do a serach on the Ebay for that unit or have it sent out for repair. Also now that you know the number when going to swap meets then keep you eye out for your specific model. Keep a small  booklet with you with the number and then you will have it ready when searching.

This is why i have collected the various catalogs to support the owning of my 1939 desoto.  Knowledge is so powerful.

Checked my Autolite catalog the Vac Adv would be VC-3147  used on :

Chry 1949-51

Desoto 49-51

Dodge car 49-51

Dodge truck 1948-50

fargo 1948-49

Plymouth 1949-50

Rich Hartung

desoto1939@aol.com

Edited November 19, 2017 by desoto1939

[Jerry Roberts]

The Auto Lite vacuum advance part number is VC 3147 for distributor number IAP 4101 1 .   ( VC stands for vacuum chamber ) 

[Ron Day]

Thanks to one and all for some very good feedback and info.   I think I can now assume to have finally found the correct distr. with the 1AP and can now search by number for the vac. adv.   Coincidently, it was the only distr, I had for which there was an electronic module application but I had not ever used it because of the bad VC.   All of which led me to the correct application.  I have now used the carb as well from the '48 block I have for parts for my 49.      Ron