Reference: Bearings used in a Ford CMP

[Hanno Spoelstra]

Jock Reed wrote:

Here is a list I compiled from the Maintenance Manual of the various drive train bearings used in a Ford CMP. It may be of use to anyone who doesn't have the Manual or Parts List.
Note: Timken numbers are considered the standard industry reference number. That number will always be cross-referenced to other bearing manufacturers' numbers.

[Hanno Spoelstra]

Re. reference numbers, there is something called the International Bearing Interchange guide, so it’s not a Timken standard but an international one.
Here’s some info on how the designation system works: https://www.skf.com/au/products/roll...gnation-system

[Jacques Reed]

Thanks Hanno,

Point taken. I guess I should have called Timken numbers a de-facto standard as so many suppliers refer to that number to find their equivalent.

I never had any problem sourcing any bearings no matter who the manufacturer when quoting a Timken number.

Has anyone ever found an equivalent for the steering end pivot pin bearings?
That request has come up a few times on websites. Listed as N.D. 928 (New Departure?)

Likewise Drive pinion pilot bearing Bower BS 13000-B.

In both cases I was able to obtain NOS ones but it could come in handy for others to know.

Cheers,

[Grant Bowker]

To the best of my knowledge, the New Departure 928 bearing was not common even when current on CMPs and I don't believe there are any currently manufactured replacements. There have been previous MLU threads discussing alternate part numbers that you could search... for example http://www.mapleleafup.net/forums/sh...ighlight=nd928

[Jacques Reed]

Thanks Grant,

That link is very informative. Glad I was able to find NOS ones a couple decades ago.

Cheers, and a Happy New year to you and everyone else on MLU.

[Bob Carriere]

.......used actual measurements of bearings ID...OD....thcikenss...seal or not.... and did their searches using the found values...... it would spit out what was available by "makers" and further searches gave us a location and delivery time and price....... the ND 928 were always elusive and usually OLD stock.....

Personnaly I have reverted to buying old rolling frames or just the front axle for parts..... took me 4 front axle to find a replacement R-Zeppa U joint and now have some spare 928 resting peace deep in a jar of engine oil.....


TIP....for future restorers...... R-Zeppa are more common on Fords but remember that GM axles were used on Ford during part shortages. ....and before dropping lots of cold cash ask the seller if he will allow you too remove the hub caps for inspection...only 3 large screws..... in the very center of the stub axle where the big wheel nut is attached look for a small hole about 1/4 inch, do not be mislead by the centering tool shallow recess used to machine the stub axle..... try inserting a slender steel rod...... should go in 3 ichnes + or _ and the hole should have machined threads...... and old dental pick is nice to carry with you. The reason for the threaded hole is that there is a screw at the very bottom that hold the R-Zeppa u-joint into the steering cup.... without it it is just a regular mass produced U-Joint.......
R-Zeppa came in two sizes.... one for the C15a and a largersize for the C60
....they were also used on.
Some early DODGE 4x4 used them but not sure if they are interchangeable....
....and you will need a FORD shop manual as it is the only one that carries details of the R-Zeppa Joint.

[Jacques Reed]

Attached from the Ford Manual is a picture of the cross section of a Rzeppa joint.

To test with the rod in the hole a small screw plug has to be removed first at the outer end of the joint. These are often butchered by curious Bubba because the slot is very shallow, and the screw is very tight. If that happens it will be difficult to remove in the field. I had two that were like that.

The rod actually bottoms out on the plunger for the centering pin which keeps the axis of the balls and cage always at half the angle between the centerline of the joint and the centerline of the axle shaft from the diff.

Cheers,

[Bob Carriere]

..... I have never seen that plug before on the many I have shopped around for. I usually fish with a dental pick to feel the threads....... that plug may have caused me to miss on some good R-Zeppa bargains......

.....and I have only seen one large front R-Zeppa axle badly crusted/rusted larger size from a busted F or C 60 snow plow.....

Never to late to learn....

[Jacques Reed]

Hi Bob,

Yes, sadly that plug may have caused you to miss out of a few!

Of interest, and bearing related also, is the balls in the Rzeppa CV joint.

I have disassembled, cleaned, inspected, and repacked a few of them and never cease to be amazed at the beautiful machining of all the parts. Must have cost a small fortune even in WW2 to manufacture them.

The balls usually have some slight pitting in them but for the amount of work they do are serviceable for a hobby vehicle.

In case I ever wanted to replace them however, I measured them with my micrometer as 0.984”. That equates to 63/64". I thought that was a strange size- Why not make them 1" exactly assuming they were made to Imperial sizes.

Out of curiosity, I then converted 0.984" to millimetres and they are exactly 24.994 mm. (25.0 mm)

I remember someone on MLU mentioned that sometimes Imperial size bearings used Metric size balls. Looks like the case here.

Shown is a NOS one I cleaned of 80 years of preservative and repacked. An engineering work of art!

Hope this is of some interest.