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Transmission pops out of gear under load on Dad's 9B.

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Early this year we tore the transmission apart on my 9b Franklin because one of the bearings was noisy. It bugged me and I broke my policy of "Don't fix things that are working" Not only did we replace the noisy bearing as long as we had it apart we replaced all five with new angular contact ball bearings. I live in a part of the country where automobile hill climbing is not a necessity and the transmission worked OK while driving around here. Then I took the car to the Trek. It would not stay in second gear on those steep New York hills. It would slowly push the lever out of the indent and finally pop out of gear. I quickly learned that I would need to let up on the power occasionally to let it pop back fully into second gear. What did we do wrong and what to do to correct it? That is the question. I'm thinking it has to be the result of tearing down and putting together with new bearings.

I use SAE 140 General Purpose Gear oil (same as the last 70 years)

Can not see any cracks in the transmission case

Indent springs have good tension.

Transmission sounds same as ever.

That kind of leaves me thinking about bearings. The race on the new ACB bearings were not stamped THRUST as the originals were. If we happened to get one in backward would that cause the shafts to be misaligned to cause gears to creep sideways? In reading the bearing data on the internet there is much said about preloading ACBBs. But I did not see anything as to whether preloading is required. Am I right or will they work OK with no preload?

The Franklin factory drawing calls for .010" thick vellumoid transmission gaskets. The thinest I could find was about .013". Thicker gasket in bottom shaft cap = less preload (or more endplay). That is if Franklin milled the case in 1919 to accomodate ACBBs (which I don't believe existed at that time). Top shaft we adjusted to no end play and probably a little bit of preload. Required the same shim as with the old bearings.

Would the increase in allowable end play in the bottom shaft cause gears to mesh improparily using ACBBs?

Should I put the old bearings back in? (except the noisy one) I did not keep track of which bearing went in which location.

That being said should I have bought radial ball bearings instead of ACB bearings? With straight cut gears I assume the bearing axial load would be rather small and radial load the major load if everything is in alignment? I went back to Applied Industrial Technologies who sold me the bearings and asked if ACB bearings were the only kind available in that size. Guess what, they are not. They never mentioned that I had the choice of radial bearings when I purchased the ACB's.


Wendell Eby

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>>Early this year we tore the transmission apart on my 9b Franklin because one of the bearings was noisy.. . . Then I took the car to the Trek. It would not stay in second gear on those steep New York hills.

Hi Bill --- Nice to see you at the Trek and especially the Series 9 . . . . the ONLY Series 9 to show up.

I am rebuilding the transmission on my 10-B right now, so what I encounter does not necessarily translate to a Series 9 transmission, but alot of it probably does. I have not seen Service Charts for Series 9 so I can't speak to them specifically.

You do want RADIAL THRUST ball bearings. The THRUST side of the bearing points to the outside of the transmission case, be it the front or rear of the case. If your parts manual or Service Chart has the bearing number, that's what you want. Don't cut corners here.

More importantly, you do want the transmission to be aligned with the engine crankcase . If this is not done one of the symptoms is popping out of gear. I've yet to develop a good way to do that on a transmission like the Series 9 and earlier cars, but I will need to soon enough for the Series 5. Bottom line is that the center of the crankshaft needs to be in the center of the transmission input shaft. A line through the crankshaft needs to run along the same line from the transmission input shaft, if that makes sense. Hopefully someone will reply and give you a method for doing this.

When I owned my Series 5 Roadster waybackwhen, it also had a problem of popping out of gear. High gear in that case. Peter Kunan diagnosed the problem as not having installed a radial thrust bearing in the output or main shaft. When I did replace it, the problem went away. I do not recall how he aligned the transmission.

I am hoping someone will elaborate further and with more intelligent conviction than I am able to do.

--Scott Dwyer

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Thanks for your reply. Why the counter man did not tell me there were two choices of replacement bearings for the numbers in the parts manual I don't know. But he is going to get a chance to tell me.

The method for aligning the transmission with the engine is described on page 73 of the Series Nine Instruction Book. And the tools for doing it are described on Factory drawings 26802, 3, 5 and 6. Attached is a photograph we took after installing the tool I made. It's not as pretty as described in the drawings but it did the job. We had to shim the transmission mounting a little bit to align it. Don't know if this is any help for your series 10

Wendell Ebypost-90005-143142154001_thumb.jpg

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Thanks for sharing this valuable information. My 9B touring has been running great for years, but if I ever need to work on it, I'll have the advantage of knowing what to look out for.

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