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***1912 Holley H1 4550 (2 Screw) Assembly***

Posted: Fri Dec 15, 2023 9:35 pm
by VowellArt
1912-1913HolleyH1-2Screw-2.jpg

Does anybody know what the part number for the bowl gasket is (I gave it 4477, but I've no idea if that's correct or not)? It isn't listed in the factory pages, so I thought maybe it's the same one as the NH, would really like to know what fits this bowl, so I can put the correct number on it

The nut on the Float arm doesn't appear to have a part number either, it's not on the picture nor on Ford's part list either, so I am assuming that it is part of the arm itself. Also there is no part number call out for those brass cotter pins either, so I took a guess. But if somebody knows what size they truly are, let me know so I can make that change, what would be even better is that there is a part number associated with them, I could add that too.

Still working on the 3 screw and as far as I can tell there isn't any difference between these two other than the 3 screw cover, not sure, but I think it is a 1913 update.

Re: ***1912 Holley H1 4550 (2 Screw) Assembly***

Posted: Fri Dec 15, 2023 10:50 pm
by Corey Walker
The bowl gasket is a cotton rope that fits in a groove in the body. Don’t know the part number.

Re: ***1912 Holley H1 4550 (2 Screw) Assembly***

Posted: Sat Dec 16, 2023 7:35 pm
by Corey Walker
There is also a fitting that is tapered and seals with the carburetor body by tightening the nut (part #4572) and the male threaded portion extends through the nut and the inlet elbow threads onto it. You have to assemble the taper fitting-nut-elbow prior to installing it on the carburetor body. Here is a crude drawing of it.
Also there is a felt gasket between the outer knurled lip of the cap (part #4574) and the threaded portion.

Re: ***1912 Holley H1 4550 (2 Screw) Assembly***

Posted: Sun Dec 17, 2023 9:57 am
by VowellArt
Ahhh, Corey, do you have the diameter of that "rope" gasket?, could it possibly be fudged with cording if the diameter isn't too of the wall. Cording has a braided exterior and a woven core. Used to grease soak it and use it in my Model A's water pump for packing. It wore better than the vendor stuff and you can find it at any fabric store...it was a hell of a lot cheaper than what the vendor's offered as well.

Woo, now that isn't something I expected on that inlet pipe....ok, I'll make that correction, thanks!.
;)

Re: ***1912 Holley H1 4550 (2 Screw) Assembly***

Posted: Sun Dec 17, 2023 10:18 am
by Corey Walker
Martin, the groove is 1/16”, 3 3-16” OD.I go to a place that rebuilds hydraulic cylinders for heavy equipment and get o-rings to go there that are the exact fit, seems to work fine. I also put an o-ring under the cap in place of the felt gasket.

Re: ***1912 Holley H1 4550 (2 Screw) Assembly***

Posted: Sun Dec 17, 2023 3:56 pm
by VowellArt
1912-Holley-H1-4550-2Screw-2.jpg
Corey, if you think of anything else let me know....you mentioned an o-ring under the cap....what size is it, so I can add that too.

Re: ***1912 Holley H1 4550 (2 Screw) Assembly***

Posted: Sun Dec 17, 2023 5:09 pm
by Allan
Corey, I always wondered how that elbow attachment was mad/assembled. It always looked like one piece, and I could never imagine how they made it.

Stan Howe was of the opinion that the two screw covers were the earlier ones. He often had to re-machine them to get them to seat properly. He concluded that the three screw type was developed to alleviate this problem. That makes sense to me.

Allan from down under.

Re: ***1912 Holley H1 4550 (2 Screw) Assembly***

Posted: Sun Dec 17, 2023 5:57 pm
by Corey Walker
3/4” ID 1” OD. The felt is still in this one.
Allan, that’s right about the 2 screw coming first I believe because it has the clamp screw for the hot air pipe like the 3 screw but it was later omitted.

Re: ***1912 Holley H1 4550 (2 Screw) Assembly***

Posted: Tue Dec 19, 2023 8:47 am
by VowellArt
1912-Holley-H1-4550-2Screw-2.jpg
Small change....it was brought to my attention that 4550 was built between the years of 1911-1912.
This was probably the 1911 version, the 1912 version would then be the 3 screw cover.