The Stovebolt Site Forums The Shop Area Engine Shop Carburetor swap

Hello all I have a 1954 chevy 3100 235 with a HYDRA-MATIC transmission. this truck has a rochester bc 1 barrel carb ( automatic Choke) . I would like to change over to a carter carburetor I understand carter made a direct change for this application would anyone know the carburetor number that I should be looking for ? Would the vacuum advance line and fuel line be in the same location? Could I use my stock air filter ? Does the carter mount the same way using insulating block Does anyone know were I can buy the needed Carburetor oR have any IDEAS !!!!!! THANK YOU VERY MUCH!!!!!!!!!!!

Carter YF2101s if you want to retain the automatic choke.

Air filter should be fine. Fuel and vac advance lines might need some tweaking.

I can’t speak intelligently to the insulating block issue, but I left mine when I swapped from a manual choke B to a Manual choke YF 2100s.

I put a manual choke YF on my 216 in place of the manual choke Rochester B a few weeks back. The fuel line, vac advance line, and throttle linkage hooked up exactly the same, no changes needed and no problem. I left the insulating block in place.

There is one on eBay currently at $85 plus shipping. It needs to be rebuilt, however it still has the Carter tag which suggests it may not have been rebuilt by a commercial rebuilder in the past. And all parts look to be there, so it appears not to have been the victim of scavengers. Good luck.

The fuel line was off by enough with the 2100 that I will have to re-plumb. Have a section of rubber in there now as a temporary measure.

The hard line to the vac advance was pretty close but had to be bent.

With a little fuel and vacuum line tweaking, the later model Carter YF made for an American Motors 232 inline six works well. I've bought a few of them on Ebay as "rebuildble cores" at bargain prices. Stay FAR away from the dirt cheap brand new "clones" of those carbs.
Jerry

One thing I’ve noticed, it looks like a large number of those AMC YF’s have the guts missing to the hot air choke. Perhaps many converted to electric?

The only thing missing is the plastic choke cover and bimetal spring. Brand new ones are available, also on Ebay, for about $10.00 each. I just bought a few. That same carb can be fitted with the later model electrically heated choke cover if someone doesn't want to use the hot air choke stove. Those carbs also have a slotted base plate, which makes them fit either 216 or 235 manifold stud spacing.
Jerry

I wonder if the throttle lever wood be the same with the HYdra-Matic trans.
George

That would be a very simple fix for anyone with basic metalworking skills if it's not the same.
Jerry

I have a 1954 3106 that originally had a 3 speed on the column but it now has an SM420 four-on-the floor.

I also have 1954 with the original Hydra-Matic.

The Hydra-Matic's throttle levers/linkages are different.

There is also a circular auto-choke baffle plate that rusts/deteriorates/gets lost and is scavenged commonly. You could make a replacement out of aluminum, but if you have a parts carb to take it from why go to the effort. Those are sometimes sold on eBay (either new or used). Usually about $15.

Does the Hydramatic have some sort of kickdown affair? I’ve never been around one of those.

It's built into the throttle linkage in the transmission- - - -totally hydraulic, no electrical component at all. There is a piece of linkage from the carburetor quadrant to the transmission. The radius of the pivot ball connection at the carb to the throttle shaft is pretty critical to the proper shift sequence, as well as the kickdown function.
Jerry