'39 throw out bearing size

HDowse

Senior Member
I'm almost done with the rebuild of the '39 early synchro style transmission thanks to Mac Van Pelt's book and many hours of learning. The last item to fit is the throw out bearing. In the picture, the hub and bearing that are on the transmission are on top with the inside and outside dimensions as close as i could get them. The critical measurement is the OD of the hub and the ID of the bearing, both nominally at 1.97". The replacement bearings I have purchased are both too big in the ID dimension and larger also in the OD. The lower left bearing is boxed as a B-7580 and the lower right is an A-7580, designed for '28-'48 transmissions.
My question is what do I have with the original hub and bearing? Do I have the correct hub for the transmission and what is the bearing? I may have to buy a new hub with bearing and hope that the ID of the hub fits the front bearing retainer. It doesn't appear to be for a V8-60 or is it? The bearing with the transmission is OK but as Mac say, it's best to replace it. Any help is most appreciated.
 

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Hello Hunt. Rockauto lists the bearings and states an inner diameter of 1.625" I will go out to the shed and measure one of mine. Back in 5 mins.

Edit: I knocked apart an old one and the bore is 2.055" as close as I can measure it.

I don't know where Rockauto got their number from, but I have bought their bearings and they did fit.

2nd edit.
the bearings I bought were national 2065.
the part number refers to the bore size (approx)
The bore is stated as 2.063"
 
Last edited:
Mart,
I’m wondering if I have a 49 bearing? But the hub for that year is unlike the 39. When I fit the A7580 on the hub it rattles around. It’s got me stumped….and with two new bearings I can’t use unless I get a new hub that also fits the front bearing retainer. Also as I look at the new bearings vs the old one, there’s more surface area for the fingers to contact and that seems more correct than the original. Don’t traipse out to the garage just yet but what’s the OD on the bearing retainer on your 39 ****** so I can check mine?
BTW, thanks for your help and your videos. They are a Friday regular which I and many others look forward to each week,
 
Hunt, the bearing carrier has a thin ring at the base which is 2.063" This matches the bearing bore.
Will send a pm.
 
Update: it appears that the carrier was turned to fit the odd bearing. On the picture the ring that Mart mentions has a few dots on it. That ring is the 1.97 measurement and also the ID of the current bearing. Notice the lower red line that just shows a slight raised relief. That shows the correct ring measurement of 2.063 and is the ID of the new bearings. (My initial ID measurements were off.) Question: is the relieved ring something Ford did or was it a one off to fit the 1.97 ID bearing? Now to find the correct carrier with the 2.063 ring.
 

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Update: it appears that the carrier was turned to fit the odd bearing. On the picture the ring that Mart mentions has a few dots on it. That ring is the 1.97 measurement and also the ID of the current bearing. Notice the lower red line that just shows a slight raised relief. That shows the correct ring measurement of 2.063 and is the ID of the new bearings. (My initial ID measurements were off.) Question: is the relieved ring something Ford did or was it a one off to fit the 1.97 ID bearing? Now to find the correct carrier with the 2.063 ring.
483275
 
The carrier is relieved higher up so only the rearmost race of the bearing is held to the carrier. The part that rotates and the internal carrier for the balls have to have clearance so they can rotate.

Mart.
 
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