Pilot bearing fit

[Russ/40]

I'm putting together a 39 transmission for my model A. I'm using a new input shaft, never fitted, and the pilot bearings i have (3 different ones ) will not slip on the pilot shaft. I have always made it a habit to use bushings instead of bearings and never had a problem. I anticipate a problem getting the shaft to fit the bearing when I try to put it all together. I cannot push the bearings on the pilot. Is this press fit correct?

[V8COOPMAN]

Press fit is WRONG! The input shaft must be free to turn inside the pilot bushing when the clutch pedal is depressed. Something is definitely not right with either the finish on the input's snout, or the bushings are improperly sized. DD

[JSeery]

Ok, I read the OP as using bearings not bushings. Is that correct?

[V8COOPMAN]

Originally Posted by JSeery

Ok, I read the OP as using bearings not bushings. Is that correct?

Good catch, Seery! I blew that one bigly! DD

[TagMan]

Use a bushing !!

[richard crow]

Sponsored Links (Register now to hide all advertisements)

tag man has it right use a bushing.

[Ken/Alabama]

If you have another input laying around check the figment of the pilot bearing on it. Whether it be a bearing or a bushing the I. D. Should be the same. Should slide on , not press fit. These days you must check everything.

[Tim Ayers]

https://www.verntardel.com/collectio.../pilot-bushing

Tardel's site has them pretty reasonably priced.

[JM 35 Sedan]

New, or so called nos parts, do not always equate to being a good part. In some cases they were rejected parts that were never used in service, and left on a dealership's shelf, only to be found years later and assumed to be nos. Bottom line is....check your parts carefully before using.

Also, in the never ending debate on bushing vs. ball bearing for a pilot bearing, I favor the ball bearing...IF... it is a known good manufacturer's brand name bearing, not made in China, seals on both sides (not to be confussed with shields), and filled with a good known high temperature lube. I did a post on this here some years ago with pictures. Unfortunately, the ball bearing pilots Ford used in some of their early vehicles were shielded or open face ball bearings which failed early due to contamination getting into the ball and race area.

Just a couple of the many posts here on bearing vs. bushing. The second thread has pictures of bushings vs ball bearings, including some failed bushings that some say could not happen

https://www.fordbarn.com/forum/showt...earing+bushing

https://www.fordbarn.com/forum/showt...earing+bushing

[cas3]

that bearing must slide on by hand or you will have a heck of time putting the tranny on the motor. your new input shaft must be too big! measure some others in your stash and see what the difference is

[Russ/40]

To restate, my concern is with a ball bearing, of which I have 3. The pilot OD is identical to the bearing I'D. Perhaps the problem is with the finish of the pilot.

[B-O-B]

What are the brgs & their #s. I believe the ID of the brg should be 17mm.I'm not sure about the OD on your A flywheel.

[Russ/40]

Originally Posted by B-O-B

What are the brgs & their #s. I believe the ID of the brg should be 17mm.I'm not sure about the OD on your A flywheel.

Bearing numbers are as such:
6203 vvc3
6203 2rsj
6203 2rsc3

I'll put the shaft in my lathe and polish it a bit.

[scrapiron]

Size on Size is a press fit, that won't work, as you know. You should be able to polish down the pilot about .0015 with some emory cloth.

[4t8v8]

I use a Consolidated #361202-2rs. Double sealed. A bit pricey. 10 years ago it was $36.
I got it at IBT. A lot of miles later it is still going strong.

[Mart]

The pilot bearing is a standard metric bearing with a 17mm bore. The bearings will be sized to a very tight tolerance. If the input shaft does not slip in, as the input is new I would suspect it is not sized correctly. Do you have another shaft you could try the bearing on? Or do you have a means of measuring the shaft accurately?

I would agree with the suggestion above that the input could be polished. If you have access to a lathe the task would be much simplified.

Mart.

[1948F-1Pickup]

Originally Posted by Mart

The pilot bearing is a standard metric bearing with a 17mm bore. The bearings will be sized to a very tight tolerance. If the input shaft does not slip in, as the input is new I would suspect it is not sized correctly. Do you have another shaft you could try the bearing on? Or do you have a means of measuring the shaft accurately?

I would agree with the suggestion above that the input could be polished. If you have access to a lathe the task would be much simplified.

Mart.

I'm in the bearing business as a sales engineer for a major manufacturer.
You would think pilot bearings are more accurate and harder to align and
less tolerant of mis-alignment. Not always the case though.
Although not a flathead application, I recently battled reinstalling a
transmission using a pilot bushing (NOS and miked), where it previously
had been installed using a pilot bearing. It was a major PITA to slide that trans in place. I ended up making two studs for the bottom two transmission
mounting holes to guide the trans in place. Didn't need that kind of accuracy when I did the trans last time (when the pilot bearing was in the crank).

[B-O-B]

Which brand of bearings are made in the USA? So far I have three different brands of(203) made off shore.

[hulleywoodworking]

Originally Posted by B-O-B

Which brand of bearings are made in the USA? So far I have three different brands of(203) made off shore.

I don't know what brands are USA made. I usually use Japanese made Nachi bearings; I've had good luck with them.

John

[1948F-1Pickup]

Originally Posted by B-O-B

Which brand of bearings are made in the USA? So far I have three different brands of(203) made off shore.

High quality 6203's are from Japan. Many of the rollers around those sizes
are as well. ABECs too. (NSK, Nachi, NTN, etc.)
I work for NTN (Osaka), our US headquarters is in Mount Prospect IL.
A number of years ago we purchased most of the old Federal Mogul manufacturing facilities back East (Elgin IL, Macomb IL, Hamilton AL, etc.)
when FM decided to cease US production and source EVERYTHING offshore.
We build our stuff in those old facilities, under the BCA & Bower trade-names, since we bought rights those too.
We are one of the only bearing manufacturers in the US. Most of our automotive hub line is produced in Elgin. (OE and aftermarket)
Timken, Schaeffler/INA, FAG also does some production here in the USA as
well. Much of their stuff is sourced globally however.