Carb spacers

All Models and Years
Post Reply
User avatar
va3rjs
Posts: 61
Joined: Sun Aug 28, 2016 4:28 am
Location: Ontario, Canada

Carb spacers

Unread post by va3rjs » Sun Oct 02, 2016 6:01 am

Hi everyone

Can you tell me if the carb spacers were included from the factory or if they were an after thought to help keep the carbs cool by adding some isolation from the hot intake/head?

I ordered a set and was just wondering if it was a do now or put off till a little later job:)

Thanks
Bob
Bob
66 Monza 2dr Converible, Automatic, (95 HP)
Marina blue, White Top, Black and White Interior

User avatar
bbodie52
Corvair of the Month
Corvair of the Month
Posts: 7488
Joined: Mon Aug 06, 2012 12:33 pm
Location: Lake Chatuge Hayesville, NC
Contact:

Re: Carb spacers

Unread post by bbodie52 » Sun Oct 02, 2016 6:49 am

The carburetor insulator is clearly shown as a part of the assembly in the attached 1965 Corvair Assembly Manual.
1965 Corvair Assembly Manual - CARBURETOR & FUEL SYSTEM.pdf
1965 Corvair Assembly Manual - CARBURETOR & FUEL SYSTEM
(3.92 MiB) Downloaded 9 times
Also, on page 9–13 of the attached section of the 1961 Corvair Shop Manual, the very first step in the instructions for installation of the carburetors on the engine reads as follows…
Installation on Engine

1. Install insulator block in place, install carburetor on intake manifold studs…
1961 Chevrolet Corvair Shop Manual - Section 9 - Fuel & Exhaust Systems.pdf
1961 Chevrolet Corvair Shop Manual - Section 9 - Fuel & Exhaust Systems
(1.31 MiB) Downloaded 9 times
This would seem to indicate that the insulator blocks have been in use under the carburetors since the very first model years. It is recommended that a carburetor gasket also be installed above and below the insulator to ensure a proper seal and to avoid vacuum leaks. The insulators themselves can develop cracks over time, and can also be damaged when they are removed from the intake manifold. The insulator should be carefully inspected to ensure that no small cracks have formed that could produce a vacuum leak at the base of the carburetor.
Carburetor Base Insulator and Gaskets.jpg
Carburetor Base Insulator and Gaskets.jpg (56.62 KiB) Viewed 263 times
The issue with heat buildup in the Rochester carburetor is also mentioned on page 6 of the attached Delco Rochester Carburetor Service Manual, as follows…
MAIN WELL INSERTS

During very hot operation, the fuel in the main fuel well tends to boil and this produces vapor bubbles. The bubbles tend to interfere with fuel flowing into the main well tube which upsets good metering. To help reduce the effect of heat and remove the fuel vapor bubbles, an aluminum main well insert is used. This resembles the main well tube and completely surrounds it. This reduces the amount of vapor getting into the main well tube, helps dissipate heat and improves hot operation of the system.
DELCO ROCHESTER - Models H, HV Carburetor Service Manual.pdf
DELCO ROCHESTER - Models H, HV Carburetor Service Manual
(1.79 MiB) Downloaded 8 times
:angry: So it would seem that heat transfer from the air-cooled Corvair heads via the integrated aluminum intake manifolds to the carburetor mounting pads and on to the carburetor bodies was a well-known problem to Chevrolet engineers, and as such it was addressed in several ways — using insulator blocks between the intake manifold and the carburetors, and internally in the design of the Rochester H carburetors using an aluminum main well insert.
Brad Bodie
Lake Chatuge, North Carolina
Image 1966 Corvair Corsa Convertible

User avatar
va3rjs
Posts: 61
Joined: Sun Aug 28, 2016 4:28 am
Location: Ontario, Canada

Re: Carb spacers

Unread post by va3rjs » Mon Oct 03, 2016 4:19 am

Thanks Brad

I will move this task up on my priority list.....like I said I have them, ordered them in my first batch of parts,from Clark's....

B
Bob
66 Monza 2dr Converible, Automatic, (95 HP)
Marina blue, White Top, Black and White Interior

User avatar
va3rjs
Posts: 61
Joined: Sun Aug 28, 2016 4:28 am
Location: Ontario, Canada

Re: Carb spacers

Unread post by va3rjs » Mon Oct 03, 2016 4:20 am

Thanks Brad

I will move this task up on my priority list.....like I said I have them, ordered them in my first batch of parts,from Clark's....

B
Bob
66 Monza 2dr Converible, Automatic, (95 HP)
Marina blue, White Top, Black and White Interior

User avatar
va3rjs
Posts: 61
Joined: Sun Aug 28, 2016 4:28 am
Location: Ontario, Canada

Re: Carb spacers

Unread post by va3rjs » Mon Oct 03, 2016 4:30 am

Ok I see what I did...... Slow internet and I submit more than once.....hmmm.....need to be more patient :)

Is there a way to delete the topic.....probably not.

B
Bob
66 Monza 2dr Converible, Automatic, (95 HP)
Marina blue, White Top, Black and White Interior

User avatar
terribleted
Posts: 2093
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: Carb spacers

Unread post by terribleted » Mon Oct 03, 2016 9:24 pm

You can delete posts. Select edit at the top right of your post, then look and the bottom of that window there is a delete box:) Or you can simply use the delete X at the top right of your post.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia

Post Reply

Return to “Ask your Mechanical Questions here”