I HAVE A 69 FORD TRUCK WITH A 360 ENGINE THAT WAS A FACTORY 2100 I CHANGED THE INTAKE WITH A FACTORY 4 AND PUT A 4100 1.12 CARB ON IT. IT RUNS GREAT EXCEPT THE SECONDARIES WILL NOT OPEN I HAVE CHECKED ALL THE PASSAGES AND AIR BLOWS THROUGH THEM THE DIGHPHARM IS NEW THERE SHOULD BE NO REASON WHY IT SHOULD NOT WORK IF YOU HAVE ANY IDEAS PLEASE LET ME KNOW THANKS

Hi.

Have you manually opened the secondaries to make sure they are not stuck ?

How tight are the screws that hold the sec. cover on ?

Open the throttle with the engine off and see if you can work the secondaries by pushing on the end of the secondary lever.

It should open smooth and not bind.

I have seen the secondary rod up against the carb body before.

Also, how is the airhorn gasket, it can leak in the back where it joins the carb body, the hole in the secondary body goes straight up and connects to a hole in the airhorn.
The passage then goes forwards and ends in a brass tube with a small hole it that points down into one of the primary venturis.

Best wishes.

Richard.

What is the carburetor number on the carb, should be on the driver side front foot.

Bill White

So Micheal,

The 4100 you have installed is from a 352/390 63 galaxie.
Couple things to check, The biggest reason (or one of the biggest reasons) is that big ackward diaphragm often does not get seated all the way around the opening or the little hole in it ends up blocking the hole from the carburetor, So first thing I would do is to check that situation out, it is also very easy to get a pinhole especially around the mounting area where most of the wears occurs. I fill mine with water and see it they leak before I install them. Associated with this is to make sure the vacuum secondary line is free from obstructions. That starts with the little tube pointed into the venturi area and then goes thru the top plate. This OFTEN gets blocked.

The other thing toi check is the butterflies are actually free and not binding up, If they do that will prevent them from opening, It pretty easy, with the engine NOT RUNNING, open the primaries to WOT then the secondaries (sometimes helps with tewo people one on each side). The secondaries shouls open seamlessly. Sometimes the secondary throttle stop (nylon pin on the choke unloader) prevents them from opening. Sometimes the throttle shaft has been bent and is causing a hangup.

And finally the other biggest reason for not working is mismatches within the carburetor to vehicle. Although the galaxie carb should be OK with the P/U in some cases I have seen this matchup cause some problems. Especially whne larger carburetors are installed onto small block with small cars (1.12's onto a 289 mustang for example). So if all else fails try a lighter spring within the housing (oh it is installed correctly right?? I have seen that as well) and see if that makes a difference.


Remember on a 4100 since we are talking about engine vacuum that operated the secondaries THEY WILL NOT OPEN or its dang hard to get them to open when the vehicle is NOT MOVING. THESE ARE NOT LIKE ANY OTHER CARBURETOR SECONDARIES. Nor will the 4100 (if you have them adjusted right) slam you into your seat, but with the air cleaner off you should be able to hear them open up and you should be able to notice the difference in the RPM.

Hope that helps,

Bill White
White Automotive