M38 Vacuum line brass fittings

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Sred
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M38 Vacuum line brass fittings

Post by Sred » Wed Dec 22, 2021 6:15 am

Any ideas on where to get:

The brass T that goes on the air cleaner: Part # A188194

and

The brass T that goes on the end of the vacuum pump to wiper line: Part #178911
1952 M38


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dpcd67
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Re: M38 Vacuum line brass fittings

Post by dpcd67 » Wed Dec 22, 2021 6:29 am

I get them locally from K&K Hardware; they are standard items. Find an old time hardware store that has boxes full of brass fittings. Or eBay.
Look in the green book page 70 and it gives all the sizes for all fittings and lines, for both early and late vacuum linen systems. M38 Reference Guide. Can't restore an M38 without it. Hard anyway.
The T at the air cleaner is 1/4 flared inverted, 1/8 male and female.
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Sred
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Re: M38 Vacuum line brass fittings

Post by Sred » Wed Dec 22, 2021 10:39 am

I tried the local auto parts store with no luck
1952 M38

Ron D
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Re: M38 Vacuum line brass fittings

Post by Ron D » Wed Dec 22, 2021 10:39 am

Hi Sred (name?),

Part number A188194 is an Eaton Weatherhead part number 552X4.

Part number 178911 doesn't compute. Are you sure it's not 178910 instead?
Part number 178910 is an Eaton Weatherhead part number 652X4.

Have you seen this link? Good information, and includes link to very helpful parts list on page 3. https://cj3a.info/sibling/m38vent/vent.htm

They aren't real easy to find (old school auto-parts and hardware stores is a good idea). You'll probably have better luck finding and buying them using the Eaton Weatherhead part numbers. I'll have to look, but may have a few in my spares that I'd part with if you run into a brick wall.

Good luck!
Ron D
1951 M38
1951 M100

Ron D
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Re: M38 Vacuum line brass fittings

Post by Ron D » Wed Dec 22, 2021 11:12 am

dpcd67 wrote:
Wed Dec 22, 2021 6:29 am
I get them locally from K&K Hardware; they are standard items.
Or maybe dpcd67 wouldn't mind a trip to his local hardware store to re-sell you a couple?
Ron D
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1951 M100

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Re: M38 Vacuum line brass fittings

Post by dpcd67 » Wed Dec 22, 2021 11:53 am

I could.
Local auto parts stores are vehicle specific and useless for this kind of thing. If you go into a hardware store (or auto machine shop) and anyone is in there under age 55, turn around and leave.
I don't use the part numbers; I look for the specifications, which are in the green book, and also in your SNL on page 78 as is your entire underwater vent system.
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Sred
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Re: M38 Vacuum line brass fittings

Post by Sred » Wed Dec 22, 2021 12:13 pm

I had part number 178911 as the brass T that the vacuum tube from the vacuum pump goes to on its way to the wiper on the left side based on the Green book page 71
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Re: M38 Vacuum line brass fittings

Post by dpcd67 » Wed Dec 22, 2021 12:26 pm

Right; that one I can't find in the SNL; look for it by description; 1/8th pipe center, ends are 1/4 inverted flare: Tee.
It is a component of the early vent system and might have been changed in the later ones, which is why it is not in our SNLs; mine is Sep 55.
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Re: M38 Vacuum line brass fittings

Post by Ron D » Wed Dec 22, 2021 1:27 pm

Sred,
Welcome to the confusing world of early vs. late M38 ventilation systems. Throw in some errors and typos in the manuals (including the "Green Book") and it can be a challenge.

As dpcd67 said, part number 178911 doesn't appear in the M38 ORD9 SNL G740 (September 1955) that I can find. Two T's are listed, A188194 and 178654 on page 78. Part number 178654 was superseded by an ELBOW (part number 325200, page 77) on engines after serial number 74419, making it part of the late vent system. The ELBOW has an Eaton Weatherhead part number 502X3.

The parts database link in my earlier post says part number 178910 is listed in the M38A1 ORD9 instead of the M38 ORD9. I didn't check that or get its description.

And I came across an old post that suggested that Eaton Weatherhead part number 702X3 is the same as part number 178654.

Maybe no help. I'm not saying any of this is correct for your M38, just suggesting that it takes some close study and cross-checking of all the resources to sort it out if you're building it faithful to the manuals.

Good luck!
Ron D
1951 M38
1951 M100

Sred
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Re: M38 Vacuum line brass fittings

Post by Sred » Fri Dec 24, 2021 7:53 am

Thank you for all the great insight and education

This is what I believe I now need

#178910 = Eaton 652x4
#A18894 = Eaton 752x4
#325200 = 502x3 or 452x3

Found this link to be helpful: http://gvrdeu.org/M38%20Service%20Manua ... .12.04.pdf
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Re: M38 Vacuum line brass fittings

Post by Ron D » Fri Dec 24, 2021 12:01 pm

Hi Sred,
Glad it helps.

And here's a link to an Eaton Weatherhead Master Catalog. Has a lot of great application information for inverted flare, pipe, and other brass fittings and tubing or pipe, including explaining their part numbering system. You might find it useful.

https://www.macpek.com/wp-content/uploa ... erhead.pdf

Good luck!
Ron D
1951 M38
1951 M100


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