The Ford Barn - Fan belt

The Ford Barn (https://www.fordbarn.com/forum/index.php)

- Model A (1928-31) (https://www.fordbarn.com/forum/forumdisplay.php?f=3)

- - Fan belt (https://www.fordbarn.com/forum/showthread.php?t=321412)

Does anyone have a part number for the fan belt so I can buy from local autoparts?

Original Ford part # was basically A8620. I don't know if that number will be useful in a modern auto parts store or not. If memory serves, the Model A fan belt is 5/8"wide and 39" long. The correct size belt will require removal of the generator pulley to get it on. If your new belt goes on without the removal of the generator pulley, then it's too long. Others can chime in here if I'm wrong about the measurements. Belt tension should be about 1/2" between pulleys.

I was wrong. Fan belt is 43" long. Thanks Badpuppy

BX40 - works great. If too small try a BX41. Readily available at local parts store.

My A has a B42 belt and I was thinking of trying a B41, will a B41fit?

Useful discussion perhaps at https://www.fordbarn.com/forum/showt...highlight=Belt

Belts do vary even with published dimensions. I think a lot of the variance has to do with "belt section" and how the belt "rides" in the pulleys.

Joe K

How to get the pulley off? Can it be done easily in the car?

IIRC, you need to remove the "bolt" that is in the center of the generator pulley. The pulley mounts with a taper and key and ALWAYS there is rust between the parts binding them together.

Tapping the pulley sideways (axial direction) at the perimeter will either loosen it up - or break it if you're too enthusiastic. Some PB Blaster may help. Pulleys are available new old stock/recycled or (not so original) as repop.

A "puller" can be used on the pulley but space is tight between the pulley and the radiator. Removal of the generator completely to perform this first removal is not hard (single bolt usually unless you have the accessory "tensioner") and makes it "workbench work" which is considerably easier and less accident prone.

If you remove the generator totally, be sure to disconnect the battery connection first lest you join the "blue spark brigade."

Joe K

Quote:

Originally Posted by 5lugnuts (Post 2188923)

How to get the pulley off? Can it be done easily in the car?

Yes. Just undo the nut on the pulley and it will slip right off of the tapered shaft. The most difficult pulley may require a very light tap with a hammer.

What about the B model belt is it the same?

Quote:

Originally Posted by Manuel (Post 2189294)

What about the B model belt is it the same?

Very similar. According to the Fordgarage.com reference I gave in link above, the B timing gear cover lug is "higher" than the Model A timing gear generator attachment point, leading to a "longer" belt for the Model B.

I have both Model A engines and Model B engines in my stable. (And a Model A engine with the Model B timing gear cover as the engine uses the Model B centrifugal advance distributor) I can't say I definitely established the Model B fan-belt as longer, but it makes sense that it would be.

More I think you kind of have to "feel out" a belt/source which is successful for you. As I have said, the belt sections between different manufacturers is not uniform and a 43" belt from one manufacturer compared to another 43" might be a completely different "fit" - the difference arising in how far "in" or "out" the belt rides in the pulley depending on that manufacturers conception/production of belt section.

Even the Gates "toothed" belt I offered as Model A option at my link above "runs" differently in the pulley "V." The toothing "squishes" to fill the V differently.

I have offered a couple of manufacturers/sources of belt by code for the Model A of which I'm familiar. Perhaps someone else more recently familiar to his Model B engine will offer similar for theirs?

Tam was helpful for me. Perhaps your supplier will know more also?

Joe K

It DOES make a difference if you have a generator vs alternator.

Regards
Bill