Pinion shaft bearing cap

[franklin28]

Whilw working on a 1931 we discovered 3 of 5 tabs broken on the Pinion shaft bearing cap part @ 35110 on the rear end causing an oil leak.The part apears to be made of pot metal., Has anyone had this problem? Has anyone made replacement parts? Is there a demand for replacement parts made of aluminum or steel? Drawing calls FM84 with a change to cast iron after 1929 but this part that broke is non magnetic!

Please let me know of your experience with this part.

Thank You.

[mikewest]

Bob , Its sounds like someone has switched it out on the rear you are working on. Is the center diff section steel?1929 and 30 were aluminum and starting with 31 through 34 were steel. I have these if you need one,Ill send it . Mike 5857381541

[franklin28]

Bob , Its sounds like someone has switched it out on the rear you are working on. Is the center diff section steel?1929 and 30 were aluminum and starting with 31 through 34 were steel. I have these if you need one,Ill send it . Mike 5857381541

Thanks for info and offer. Yes, I would appreciate it if you would send one.

Thank You,

Bob

[franklin28]

Hopefully the one you send will be steel and not pot metal. However, beggars can't be choosers.

Thank You. Mr. A will be pleased.

Bob

[mikewest]

Bob, The steel section I was refering to (31-34) is the center section of the rear axle housing . Im sure you already now that owning several 1932 Franklins. I wasnt aware of a change in the material these housings were made of. My 32 convertible needed that piece to be remade as it was in poor condition . I had one made out of aluminum, and installed a modern seal. If I have a steel one Ill send it other wise it will be pot metal. Mike

[odat]

Should I look at makeing some new ones to print? Has anyone done this allready or in the past?

[hook]

It would be nice to have new ones made with provision for modern lip seal.

[Franklin31]

Concur~~Sounds like a good club project to me.

[odat]

Ok it can be made "no problem"

Do we want them made in aircraft grade alum or steel?

The alum will replace the pot metal, and be light weight. The steel will be made to originial specs but only for the later models.

[hook]

Ok it can be made "no problem"

Do we want them made in aircraft grade alum or steel?

The alum will replace the pot metal, and be light weight. The steel will be made to originial specs but only for the later models.

I think the aluminum would be great and make it with a press fit for seal #CR21069. This seal is the one recomended by Jeff Hasslen when he sends out the new gears. It will fit from 28 to 32.

[odyssey]

Making new pinion housings might be a good idea. We have made a couple over the years to replace housings with broken ears when installing the 21069 seal. But the original housings are usually o.k. and work with the 21069 seal as long as the seal is not pressed into the housing, but rather set up for a very light (thumb press?) fit or slip fit with loctite. This ensures it will not develop a leak.

It's also important to note that the rear axle housing breathes with temp changes. Originally, I think the breathing happened through the pinion felt seal more than the axle felt seals as the axle seals fit more tightly. With a positive seal on the pinion, all breathing must go through the axle seals, raising the possibility of pushing axle grease out and onto the brakes. A drain system is provided in the backing plate to avoid this, but it still happens.

Installing a breather in another location on the axle housing eliminates any chance of lube getting out onto the brakes. We've installed many breathers in lots of ways, so I don't know that I can say one way is best. Perhaps others can weigh in.

But the main point is that it's important to install a breather when installing positive lip seals on the rear axle.

tom

[franklin28]

Wow, I love this. Sharing of information like this is awsome and we all benefit and learn something.

Thanks for all reply's.

Bob

[hook]

I agree with Tom 100% concerning housing breathing and the need to install a breather when using the tighter modern lip seal. However, these pot metal caps deteriorate with age (they get brittle, they break on their own and they crumble even without putting presure on them) and these things are in their 80's. Gee I'm deterioting myself in my 60's. I think we have a need for new ones, but if only one type were being made I think I would opt for the original. That way it would satisfy the purist or those that don't want to ad a breather in the housing or rear cover and it allows those that want to go for the modern seal to have the end turned out to a press fit for the 21069.

Bill

[odat]

I could make the new one ready for the modern seal and then have and insert of the same material that could be pressed in so it becomes the oringinial style.

[Franklin31]

Richard, think you should make one just to find out lathe time required. About the simplest part for a SB 9" on the Franklin, but still takes time. Programing would just about kick these out. Do it; I want one. Oh, agree on going with the CR seal, can't imagine anyone wanting felt !! Richard D.