1972 Distributor questions
Thread Starter
Race Director
Joined: Oct 2005
Posts: 12,470
Likes: 1,548
From: Camp Verde AZ
C1 of Year Finalist (performance mods) 2019
2017 C1 of Year Finalist
1972 Distributor questions
Doing a ground up rebuilt on the dizzy that came with the car. New oiled packing around upper bushing, new seals, new B26 vac can, lighter advance springs, everything except new bushings.
November 18, 1971 build date on car.
The tag is an 050 dizzy, which is correct for base 350 motor.
The tag date is 1D9, which I believe is incorrect, an April 1971 date?
Could this be original, or did someone swap out a dizzy?
Someone looks to have gotten creative with the housing, there is fine thread 5/16" hex bolt and locknut sticking out the rear of the tach drive housing, instead of an internal thrust button. Have to plug that with a set screw drilled for a bushing (or, just a brass setscrew) and use some epoxy to make it look unmolested, which brings us to our next question:
Were the visible portions of the housing of these painted black, or were they natural cast finish? If black, was it gloss black, semi gloss, SEM trim black?
Thanks,
Doug
November 18, 1971 build date on car.
The tag is an 050 dizzy, which is correct for base 350 motor.
The tag date is 1D9, which I believe is incorrect, an April 1971 date?
Could this be original, or did someone swap out a dizzy?
Someone looks to have gotten creative with the housing, there is fine thread 5/16" hex bolt and locknut sticking out the rear of the tach drive housing, instead of an internal thrust button. Have to plug that with a set screw drilled for a bushing (or, just a brass setscrew) and use some epoxy to make it look unmolested, which brings us to our next question:
Were the visible portions of the housing of these painted black, or were they natural cast finish? If black, was it gloss black, semi gloss, SEM trim black?
Thanks,
Doug
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
Doug -
The finish on the distributor depended on which plant assembled and supplied them (GM never "sole-sourced" anything). The "correct" finish is a satin black. When working on these cars when they were brand new, it was very frequent to see the new Vettes delivered with bare, as-cast distributors, which had light surface rust on them right from the factory. Either finish is actually correct, although most NCRS people probably don't like to recognize the shoddy, as-built, un-finished distributors that were quite common.
Lars
The finish on the distributor depended on which plant assembled and supplied them (GM never "sole-sourced" anything). The "correct" finish is a satin black. When working on these cars when they were brand new, it was very frequent to see the new Vettes delivered with bare, as-cast distributors, which had light surface rust on them right from the factory. Either finish is actually correct, although most NCRS people probably don't like to recognize the shoddy, as-built, un-finished distributors that were quite common.
Lars
Melting Slicks
Joined: May 2002
Posts: 2,476
Likes: 756
From: Laporte, IN
Doing a ground up rebuilt on the dizzy that came with the car. New oiled packing around upper bushing, new seals, new B26 vac can, lighter advance springs, everything except new bushings.
November 18, 1971 build date on car.
The tag is an 050 dizzy, which is correct for base 350 motor.
The tag date is 1D9, which I believe is incorrect, an April 1971 date?
Could this be original, or did someone swap out a dizzy?
Someone looks to have gotten creative with the housing, there is fine thread 5/16" hex bolt and locknut sticking out the rear of the tach drive housing, instead of an internal thrust button. Have to plug that with a set screw drilled for a bushing (or, just a brass setscrew) and use some epoxy to make it look unmolested, which brings us to our next question:
Were the visible portions of the housing of these painted black, or were they natural cast finish? If black, was it gloss black, semi gloss, SEM trim black?
Thanks,
Doug
November 18, 1971 build date on car.
The tag is an 050 dizzy, which is correct for base 350 motor.
The tag date is 1D9, which I believe is incorrect, an April 1971 date?
Could this be original, or did someone swap out a dizzy?
Someone looks to have gotten creative with the housing, there is fine thread 5/16" hex bolt and locknut sticking out the rear of the tach drive housing, instead of an internal thrust button. Have to plug that with a set screw drilled for a bushing (or, just a brass setscrew) and use some epoxy to make it look unmolested, which brings us to our next question:
Were the visible portions of the housing of these painted black, or were they natural cast finish? If black, was it gloss black, semi gloss, SEM trim black?
Thanks,
Doug
Doug
Your Distributor build date would be April 9th 1971 for judging this would be outside the norm of 6 months prior to the Corvette assembly date. I am not saying it is not the original as the 050 was used from 1970 till at least 1972. It is just not typical of the majority of Corvettes that have been judged. One question is the ID band silver on the outside exposed area and Red anodized on the back side?
The original Tach drive gear button was nylon. Was just pressed into place original part number 1957329 see photos below.
From original Corvettes we have judged a semi gloss black finish has been observed. Have we seen every Corvette no but from our hundreds of original Corvettes judged this paint was on the majority. Also you would have a Green paint dollop color code for the worker at the factory assembly line. Making it easy to pull the correct distributor for the car. The photo of the green dollop is from a 6400 mile 1972.
Last edited by PJO; Jan 10, 2022 at 09:21 AM.
Thread Starter
Race Director
Joined: Oct 2005
Posts: 12,470
Likes: 1,548
From: Camp Verde AZ
C1 of Year Finalist (performance mods) 2019
2017 C1 of Year Finalist
Well, the distributor turned out beautiful, Turned up a 5/16'-24 threaded brass plug on the lathe, installed it where the bolt was, doctored up the outside surface so you can't see the plug, new paint (inside and out), all metal parts, screws etc, wire brushed. Fired right up once back in the car, the better vac can is noticeable, i am sure the lighter adv springs will be also.
The original upper grease seal had disintegrated, and the oil soaked sawdust was pretty hard, some packed cotton and 30 wt oil in the cotton will keep the upper bushing well lubed. Also set the end play at about .025" on the tach drive driven shaft.
Doug
The original upper grease seal had disintegrated, and the oil soaked sawdust was pretty hard, some packed cotton and 30 wt oil in the cotton will keep the upper bushing well lubed. Also set the end play at about .025" on the tach drive driven shaft.
Doug
