Carb overflowing

[jopizz]

I'm not sure if it makes a difference but I always use the gasket with the round holes. I think the rebuild kit gives you both.

[redstangbob]

The gasket under the carb should be the 4 hole, other gaskets may cause vacuum leaks. There's a pin on the right side linkage that closes the secondaries, if it's plastic it may be broken off. This pin is a must, you can fab one or get them from some of the carb rebuilders.

[jopizz]

Great point. I forgot about that pin being on there. That would keep the secondaries from closing if that was missing.

[davidvend]

I just got back from getting a 4 hole gasket I will replace it today. The pin on the back is new and not broken works freely with no binding. I do believe it is the gasket I'm glad I save the old one. NAPA told me the old gasket was from a newer carb 61 or 62 but he thought the new gasket that came in the kit would allow to much vacume coming from the venturies and sucking in the diaphram and allowing the secondaries to stay open. The gaskets that came in the kit 1) had a large opening and only sealed the edges 1) had 4 holes and the center was missing the holes were like 3/4 of a circle. I'll let you know what I find out.

[jopizz]

The pin we're referring to isn't on the back. It's on the passenger side linkage where the fast idle screw is. It manually closes the secondary throttle plates when the primaries close. I really don't think the gasket is your problem.

[davidvend]

Yes the pin is their, it is the secondary operating rod which manually closes the the secondary operating diapham which stayed open. The rod your referring to is on the side and goes to the back pivot plastic arm. Their is a vacume inside the carb that goes tru the center of the air horn which I think was sucking to much and kept the secondaries open. When I shut off the motor the secondaries would close. I have put on the new 4 hole gasket mounted the carb and ran the engine flooring the gas petal and now it appears to close. I haven't driven the car yet we'll see what happens after I drive it.

[davidvend]

I now have a great running 352 it seems it was the carb gasket. I stretched the diaphram return spring a little for some more pressure and changed the carb gasket. I drove the car and after driving it to warm up I was flooring it I couldn't believe the rear butterflies don't stay open anymore. All is well. I believe that you must put on a 4 hole gasket with the 4100 carb as this has solved my problem. Thank You all for your help. What a great group of detailed mechanics that know your stuff. - David

[jopizz]

Great news. I never would've guessed that the gasket would cause that problem. I'll file that away in the ole memory bank.

[davidvend]

jopizz thanks for all your help I'm not sure I would have tried to rebuild it without your encouragement. Isn't it amazing that a gasket would allow so much vacume in such a small area. Redstangbob must have seen this before as he said in his post he only uses a 4 hole gasket.

[jopizz]

You're welcome. Glad I could help.

[redstangbob]

davidvend, glad things worked out. Yes I've been down this road before . The best lessons are the ones we learn the hard way, that's how I know about the 4100 carb . Good luck with your project, and ask the group about anything that troubles you, someone here has the answer.

[Jimz Bird]

Here is some more info on how to ID the venturi size of these carbs.

"All Ford 2V and 4V carburetor (mfg. since 1960) have 2 markings to easily determine what they are. On the drivers side of the carburetor - right behind the accelerator pump rod - you will find what appears to be a “clockface”. Inside the “clockface” in raised characters 4100’s will read 1.08 or 1.12*. Approximately one inch directly below the “clockface”, on the mounting flange (or toe) of the carburetor, there will be stamped on engineering number. The numerals in the “clockface” refer to the primary venturi diameter in inches. The “1.08” is a 480 CFM carburetor - while the “1.12” is a hefty 600 CFM. (In 1958 only Ford made a 1.19” venturi (670 CFM) you’ll probably never see one of these)"

From here:

http://www.ponycarburetors.com/default.asp?page=faqdetail&id=22

Some good info on that site.

Pony has been around a long time and "generally" they get good reviews BUT (and this is a BIG BUT) they are VERY expensive and as of late there have been some to say they are not as good as they used to be.

They guy (2nd owner) who I got my 56 from had them rebuild the Holley 4000 "Teapot" on mine and paid $479.50 to have it rebuilt. A kit is about 50 bucks. I would have bought a kit or two and screwed with it myself till it worked.