Thursday night I was returning from a C.A.R. club meeting. I was driving my Dads 30 A roadster. The A-Bone is powered by a hot B motor and was rolling along nicely until the rear locked up. To shorten the story, the correct diagnosis was a seized front drive shaft bearing. Disassembly showed the drive shaft was ruined and needed replacement. Not wanting to completely disassemble the rear axle as it was rebuilt by me several years ago and functions just fine. I needed to devise a method to pull the drive shaft and pinion as a unit. Some may remember my post showing the tool that I fabricated to press the pinion from a banjo rear. A slight modification to that tool and three additional parts and instant Model A pinion puller (perhaps for those Mercury pinions too). The ten minutes spent fabricating this device saved me hours of work. I believe the pictures will explain it better than my words can. Please note the second to last picture shows tool as used to remove later style banjo pinion for clarification only. Regards, Ron
Cool, I'm tearing apart a Model A banjo now. Do I understand this correctly: It appears the pinion is trapped between the bearing cup and the pinion nut. The outer bearing is trapped by the adjusting nut/lock plate/lock nut. And here's the tricky part, once****emble only the friction of the inteference fit on the bearing cup holds it all in place? Seems like over time the pinion depth would change as the bearings wear or if the bearing cup would work it's way out. Anyone know if the pinion yoke used in the store bought Model A open drive conversion is a specialty piece or an "off-the-shelf" item? I'm wondering if I can cut down my drive shaft, spline it appropriately and bore/tap to make my own open drive conversion. If the pinion yoke something I can get from a salvage yard, it seems do-able for much less.
Here is a thread that might help you. I made my own conversion. http://www.jalopyjournal.com/forum/showthread.php?t=324073&highlight=banjo
Thanks Tman, I've already read that one. Been searching on it for about a week now. I'm hesitant to weld the yoke to the pinion stub shaft because I don't know how hard it would make removal/installation. I'm using a Model A banjo (gonna be 4 powered) until I prove I can break something. In your other thread you mention a hole to access the coupler to pin it to the pinion shaft, I don't know what you mean by this. Is it a later model banjo thing?
No, I am putting a hole in the new short housing so I can pin the coupler/yoke to the pinion like it originally was held.
No, I get the addition of the hole in the housing. I meant is the pinion being pinned to the stub shaft a later model banjo thing. The model A banjo I have has the pinion held on the driveshaft by a nut.
not to sound stupid, is the bearing bottomed out in banjo housing? If changing the drive shaft only, how do you know the pinion gear depth? what holds the pinion gear on the end of the shaft? I understand the puller but everything else is muddy do to not ever tearing apart a A bonne rearend. I am thinking of putting a overdrive unit in in place of the torque tube, and it uses a short piece of drive shaft that goes into overdrive(BW r10). Hope this applies to what you are doing, if not might be a new post thanks Ken
The pinion bearing bottoms on the banjo housing. Therefore upon reassembly returning to it's original location. The "A" drive shaft is tapered and keyed like the axle (same taper) and held tight to the pinion with a nut. Hope this helps. Regards, Ron
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