Carter Carburetor Thin Gaskets 1A-65

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DieFledermaus
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Carter Carburetor Thin Gaskets 1A-65

Post by DieFledermaus » Tue Dec 21, 2021 2:00 pm

Hi Gee,
The purists are indicating that the carb difuser gasket should also receive two Carter thin gaskets, one on top and one on bottom.
Part #1A-65
My jeeps run fine without these...just curious. Your comments? Does the thin gasket better permit air flow through the small port located at the base of the YS637S?
AUG 1944 MB, US NAVY
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Re: Carter Carburetor Thin Gaskets 1A-65

Post by Ron D » Tue Dec 21, 2021 5:50 pm

Hi Mike,
I don't know about the purists or the port hole in the base you mention, but my copy of the M38 Engine Manual (TM9-1804A, June 1951) paragraph 95 on page 96 says to place a carburetor gasket and the diffuser on the intake manifold and install the carburetor. So it looks like at least one thin gasket is called for.

I can't find anything in the manuals describing the purpose of the V-diffuser, but have read in the forums that it's supposed to serve two purposes: (1) help atomize the fuel in cold weather, and (2) help insulate the carb from manifold heat.

I also read the purists advice for two thin gaskets, one above and one below the V-diffuser, and I followed it. Figured one more gasket couldn't hurt. Mine runs good too.

The reproduction diffuser I bought came with copper bushings around the stud holes that are supposed to crush for sealing. I've seen photos of NOS diffusers without them. Some folks in the forums say to cut those bushings off because they're difficult to crush properly and can be prone to leaking. So I dremel-tooled mine off per the advice. Using the thin gaskets above and below made me feel better. :lol:

Good luck!
Ron D
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DieFledermaus
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Re: Carter Carburetor Thin Gaskets 1A-65

Post by DieFledermaus » Tue Dec 21, 2021 6:53 pm

Hi Ron,
The thin gaskets were recommended by Wes K. At our WWII Jeep restoration shop, we always avoided the repro difusers with the copper grommets...always got vacuum leaks. Plain work much better. Where can I buy som thin gaskets?
AUG 1944 MB, US NAVY
MAR 1952 M38
APR 1952 M38
1957 F2A AERODROME TRAILER
1993 M101
A & P mechanic
Delaware 19958

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Re: Carter Carburetor Thin Gaskets 1A-65

Post by Scoutpilot » Tue Dec 21, 2021 11:24 pm

For many years now, I have installed only the diffuser gasket between the carb and the manifold. I have found that applying 30-35 pound-feet of torque to the nuts is sufficient to properly crush the copper rings with no vacuum leaks.
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Re: Carter Carburetor Thin Gaskets 1A-65

Post by dpcd67 » Wed Dec 22, 2021 12:14 pm

A: Never heard of using any extra gaskets from Purist, whomever he is, or anyone else.
B: I just use the one thick gasket, as Scout indicates above.
C: Done it several times; no issues noted.
D: Not sure what the real problem is; maybe a solution in search of one.
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Re: Carter Carburetor Thin Gaskets 1A-65

Post by Ron D » Wed Dec 22, 2021 12:21 pm

dpcd67 wrote:
Wed Dec 22, 2021 12:14 pm
D: Not sure what the real problem is; maybe a solution in search of one.
There's no problem. The OP asked a question. Did you read it?
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Re: Carter Carburetor Thin Gaskets 1A-65

Post by dpcd67 » Wed Dec 22, 2021 3:09 pm

I never read the questions before I answer; faster that way.
Actually, I am responding to the "purists" thoughts that two extra gaskets are required; not that the OP is asking about it.
I do not follow the "purists" advice to use two extra gaskets because I never heard of it. My jeeps all run fine that way. So my point D is better stated: Since I do not have any problems with using ONE large gasket, I do not understand what the problem is or might be, on other people's jeeps. This is not directly related to any problem the OP may, or may not, have, or anticipate having, or is asking, or to which he may, or may not be, alluding.
I follow ScoutPilot's guidance instead.
Sorry if I wasn't clear.
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Re: Carter Carburetor Thin Gaskets 1A-65

Post by Ron D » Wed Dec 22, 2021 3:19 pm

dpcd67 wrote:
Wed Dec 22, 2021 3:09 pm
I never read the questions before I answer; faster that way.
I didn't realize speed was more important than being on topic in these forums. Oh well....live and learn.
dpcd67 wrote:
Wed Dec 22, 2021 3:09 pm
I do not follow the "purists" advice to use two extra gaskets because I never heard of it.
If you had heard of it, would that make it ok?

The manual calls for one gasket with the diffuser. Is the manual ok?
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Re: Carter Carburetor Thin Gaskets 1A-65

Post by dpcd67 » Wed Dec 22, 2021 3:32 pm

No to all your questions.
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Re: Carter Carburetor Thin Gaskets 1A-65

Post by DieFledermaus » Wed Dec 22, 2021 4:17 pm

Thank you for your comments, gents.
Enjoy the holiday!
Cheers,
Mike
AUG 1944 MB, US NAVY
MAR 1952 M38
APR 1952 M38
1957 F2A AERODROME TRAILER
1993 M101
A & P mechanic
Delaware 19958


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