Difference between an A and B

KerryM · Jul 11, 2011

Can the experts tell me the difference between an A and B? As far as parts interchange? I am fixing up a B, found an A parts tractor. One specific area is the seat and brackets. But what about the interchange of parts on the rest of the tractor too. Thanks

Red Dave · Jul 11, 2011

There are a great many parts on an A that will fit a B. Engine, clutch, transmission, final drives, wheels, fenders, all are interchangeable. The hoods & gas tanks will interchange except that 1939 & '40 sheet metal is different than '41 & later sheet metal. Grills are different between an A & a B too.

The seat will interchange except that the B needs the extra bracket that attaches the right-hand support to the right side differential housing, everything else should fit right on.

The differences are the front axle & steering bolster, the drawbars, the foot pan, the pedal mounting and the pedal guard, & of course the length of the differential shafts and their housings are different too.

sflem849 · Jul 11, 2011

They are pretty much the same.

Don't forget you can go on the Case website and look at the parts books. There is no doubt when the part numbers are the same.

old · Jul 11, 2011

Depending on the years of the 2 almost all parts will swap out. Reason I say depending on year is the early ones and the late ones used different types of latches on the hood. I took 2 Bs and 1 A and built a BA out of the 3 of them. Reason I call it a BA is because front the transmission forward it is a B but from the Transmission back it is an A

KerryM · Jul 11, 2011

So you basically ended up with a narrow front A?

I did look at the Case parts site, indeed the seat brackets on an A & B are the same, minus the lower bracket on the A. I assume the A has a flange on the axle casting that the seat bracket bolts to? Dang, I wish I had paid attention when I went to Farmall Land...the A & B were sitting next to each other.

Red Dave · Jul 11, 2011

On the A & the BN the right side seat bracket bolts to the same bolts as the fender.

old · Jul 11, 2011

Ya pretty much a A with the narrow B front. I did that because I had an A that had a disagreement with the tree when it rolled down a hill on its own and had a B that had a number of problems. Could have just fixed the B but I have a sickle mower that fits the A but will not fit a B so I built my BA. It has 5 tires on it. Duals on the left side rear and a single tire on the right. Wheel weights on both sides and the trike 2 tire set up up front. Looks a little odd but it sure does cut nice now that I rebuilt the sickle bar

Scotty HOMEy · Jul 12, 2011

Seat and supports are the same. The seat platform and the guard under the pedals were wider on the B, and that extra width means the pedal shaft/cam out to the right brake is also longer on the B. (A/BN were the same in all these respects.)

As others pointed out, the A won't have the brackets that mount to the platform and hold up the seat supports, as on the A/BN, that outer support mounted up to the final drive with some of the same bolts that hold the fender on.

Except for the front casting and grille (different cutout to deal with the different shape of the casting), and as long as you're not dealing with a differnece in the fasteners (Dzus vs. bolts and hooks -- earliest 70,000 or so tractors of both models were Dzus) for the hood and grille, pretty much everything else is interchangeable. If one of them is Dzus, there's also the chance that the magneto grounding is different. The early ones had a rod that operating a grounding tab at the magneto. Later (and most of them) used the single-pole mushroom cap switch to ground the magneto through the chassis of the switch.

Difference between an A and B

KerryM

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Red Dave

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sflem849

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old

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KerryM

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Red Dave

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old

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Scotty HOMEy

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