Author Topic: Carburetor plating the steel parts  (Read 1241 times)

Offline ng8264723

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Carburetor plating the steel parts
« on: October 17, 2017, 05:23:26 PM »
Any recommendations?  I had the pot metal done by the carb shop and it looks great.  I need to get the bolts done where they zinc or cadmium??

Offline 7Lscjracer

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Re: Carburetor plating the steel parts
« Reply #1 on: October 17, 2017, 07:00:38 PM »
Are you talking about a Holley 4150 series?
Easy enough to just buy new float bowl machine screws from Holley with their good to go finish.
69 Mach 1 San Jose Nov. 68 build
Bought May '81, sold Sept '20

Offline J_Speegle

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Re: Carburetor plating the steel parts
« Reply #2 on: October 18, 2017, 12:54:36 AM »
Any recommendations?  I had the pot metal done by the carb shop and it looks great.  I need to get the bolts done where they zinc or cadmium??

Yes what type of carb - Holley or Autolite?  And which "bolts"?

Normally your going to have a few to allot of arms, brackets and rods also that can be finished a number of different ways originally depending on the carb type
Jeff Speegle

Anything worth doing is worth doing concours ;)

Offline ng8264723

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Re: Carburetor plating the steel parts
« Reply #3 on: October 18, 2017, 09:41:14 AM »
Holley it's th original carb for my 428 SCJ 1970.  All the little screws and brackets

Offline 7Lscjracer

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Re: Carburetor plating the steel parts
« Reply #4 on: October 18, 2017, 01:54:54 PM »
I have one of those 70 Holley/Autolite manual choke carbs disassembled on the shelf.
I bought it NOS, but ran it on a car for years so it's not much help anymore as far as identifying plating types goes sorry to say.
Some of the original small pieces are of different construction than what is currently serviced by Holley though.
You'll have to replate those, but others you could buy new.
However, you might as well replate everything since it would all be covered by the minimum charge.
Cad plating is very expensive these days due to ever increasing environmental regs, but zinc not as much.
The yellow chromate is an additional process, a conversion coating to give it the gold hue on either type of initial plating.
All I can say is carefully inspect each small part for traces of original finish after spray cleaning with carb cleaner.
I don't think any of those parts would have been cadmium plated because it's never been cheap.
I had a bunch of small parts cadmium plated in the early 80's, they called it barrel plating, and the minimum was $100 for whatever fit in.
I'd hate to think what it would cost now.
My money's on some silver zinc and some yellow zinc parts.
I'm sure any number of people on here will chime in with pics of their concours or NOS carbs.
69 Mach 1 San Jose Nov. 68 build
Bought May '81, sold Sept '20

Offline J_Speegle

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Re: Carburetor plating the steel parts
« Reply #5 on: October 18, 2017, 02:42:24 PM »
..................... I need to get the bolts done where they zinc or cadmium??

With the new info the bowl screws, and small screws that hold the brackets to the carb and the accelerator pump to the bowl I believe were originally dichromate. Make sure the bowl screws (the long one that go in through the bowls and into the main body) are the correct originals (use a flat headed screw driver) not the hex heads that Holley used later in production and over the counter as replacements

Allot of the carbs you will see that have been restored will have everything dichromated where IMHO on originals many of the rods and some arms were not (attached after other sections were plated)
Jeff Speegle

Anything worth doing is worth doing concours ;)

Offline Bob Gaines

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Re: Carburetor plating the steel parts
« Reply #6 on: October 18, 2017, 04:23:08 PM »
Here are some pictures I took today of a C9AF-M (428 4 sp) carb with a 921 date. This is a unused NOS carburetor with a date right in the middle of 69 production. The hardware finishes should be typical of the finish that would be on a assemblyline carb.  A automatic will have the addition a kick down lever which was gold with silver screw.
Bob Gaines,Shelby enthusiast, Shelby collector , Shelby concours judge SAAC,MCA,Mid America Shelby

Offline J_Speegle

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Re: Carburetor plating the steel parts
« Reply #7 on: October 18, 2017, 08:50:19 PM »
A shot of the manual choke and related pieces Sorry looks to have been in storage or slightly used at one point


Jeff Speegle

Anything worth doing is worth doing concours ;)