How To: C15a Wire-3 restoration

[Grant Bowker]

Your image of the tool is the one I see in MB-C2. MB-C1 shows a 2 armed puller, but gives the same tool number as shown in your image. Odd.
Based on the image, I would have interpreted the gear involved as being the spiral type mounted to the end of the transfer case idler shaft. I'm not expert but would interpret this as the driving gear and the smaller gear that engages both this one and the speedometer cable as the driven gear. (Both fall in parts group 4.337 so the diagram doesn't make it clear which is which.)

The gear I think of as driving, Chevrolet number1809534, is listed in a Ford parts book as equivalent to C01Q-17285-A and is described as having 4 teeth while a couple of other driving gears with only Ford part numbers are described as having 5 teeth. I think this is the gear you mention on LWD's site: https://www.lwdparts.com/product/gear-speedo-driven-2/ which seems to be the one listed as being common to the Chevrolet. LWD have another listing for a speedometer gear, driven that is the other part of the speedometer gearing https://www.lwdparts.com/product/gear-speedo-driven/ Be cautious with terminology to be sure you get what you need.
C01Q-17285-A is listed as appling to F15A, F30, F60S, L, H and FGT. 1809534is listed in Chev parts books as suiting C15A, C30, C60 S, L and X and CG. I didn't check any of the armoured vehicle books.

This gear is listed in the C15A0-04 parts list as one of the * parts, "peculiar to CMP vehicles", but is not so marked in the C60X-04 list. Puzzling.

Most of the non-CMP parts books I have seem to treat the driving and driven gears as items to be ordered as a matched pair rather than individual gears. These sets are all 6 digit numbers instead of 7 digit, suggesting earlier the CMP parts may be later (possibly by being designed to match the transfer case shaft instead of the transmission output shaft as in 2WD civilian pattern trucks. The Modified Conventional Pattern Chevrolets seem to follow the civilian method of treating the gears as "gear unit, speedometer drive".

How badly damaged is your gear? Any chance the driven gear rides on the part that escaped damage?

[Jordan Baker]

Thanks for the help. My bad on the other part number. I read off he wrong line in the parts book when I was typing out my post.

The worm gear on the end of the idle shaft should be GM 1809534 Gear Speedometer Drive ( 4 teeth). From what you have, this part is the same as the Ford C01Q-17285-A?

Also here is the picture of different tool for removing the worm gear.


I stopped off at the shop tonight and we might be able to make a copy of the puller as found in MB-C2. He didn’t think where I had the small chips would be any issue as the other gear should just be riding in the middle.

[rob love]

There does not appear to be anything special about that puller. I'm pretty sure I have that in both OTC and snapon.

I think a small to medium bearing puller (the plate type that has two halves) and a little heat from a propane torch would make quick work of that job, and provide much more support to the gear.

[Jordan Baker]

I tried the plate type of bearing/gear remover and it quickly chipped the bottom of it so I stopped. I’ll try some heat on it tomorrow.

[David Herbert]

Originally Posted by Jordan Baker

I tried the plate type of bearing/gear remover and it quickly chipped the bottom of it so I stopped. I’ll try some heat on it tomorrow.

Did you use it flat side to the speedo drive gear ?

David

[Lynn Eades]

Jordan,once again, no knowledge on my part. What does the nut behind the gear do?
Can you use it to push the gear a bit?
If you heat the gear, a quick heat like oxy accetylene will get you the gear hot without the shaft getting hot at the same time. If you use the ring gear fitting method of using a wooden match to check the heat. That is, do not heat past the point where a match will char or "slips' easily sideways (loss of friction)
Something like a chain vicegrip might swing it off, when it is hot. I hope this lot helps.

[Grant Bowker]

A PDF of the pages on speedometer parts from Ford book SE 39-42 is attached to let you confirm.