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Removing tach drive gear in Prestolite/MP distributor

friendofvirgil

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I'm tearing apart an old cast iron, tach drive, point distributor for an RB engine. Does anyone know the method for disassembling the tach drive gear assembly from the housing? I've removed the main shaft and advance weights. All that remains is disassembling the tach drive gear stem.
 
Never been into a tach drive. Any chance there's a snap ring/wire in there, that keeps it in place?
 
a pic would help.
Mr. vance.dykes, you are correct. See photos. I'll check to see if my old factory service manuals for 63 Dodge or 63 Plymouth have anything.
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what do you see down in side the housing i see the shaft come out with the tack drive in . do you feel a step to indicate a separate insert in the housing. it is possible that the very end may / should slide out as an o-ring may be frozen [ see the space at the end before the threads] soak it in a carb tank to clean and dissolved the old rubber. yes that may be a screwdriver slot when i had to repair old tack drive on vetts that was how they came apart but they had a full slot across them.
 
that may be a screwdriver slot when i had to repair old tack drive on vetts that was how they came apart but they had a full slot across them.
Don't think so. That slot should be the cable drive, cable end would have a key that fits into it.
Seal 'cup' on opposite end, might be how the tach drive shaft comes out.
Waiting, and watching...
 
what do you see down in side the housing i see the shaft come out with the tack drive in . do you feel a step to indicate a separate insert in the housing. it is possible that the very end may / should slide out as an o-ring may be frozen [ see the space at the end before the threads] soak it in a carb tank to clean and dissolved the old rubber. yes that may be a screwdriver slot when i had to repair old tack drive on vetts that was how they came apart but they had a full slot across them.
Fran Blacker and vance.dykes that is not a screwdriver slot similar to the screw-in head type used on the Corvette distributors. miller is correct that the slot is for the key, or tang, on the cable. This tang style is more common on Mopar drives. Generic Motors used a square-formed end on the drive end of the cable.

miller, hopefully Auto Lite or Prestolite or whoever the manufacturer's name really is, didn't add a snap ring inside behind that cup that looks like a reverse freeze plug. I used a small brass drift bar and hammer to try tapping on the face of the drive slot to see if it would move. Reasonable knowledge of force energy tells me I've hammered hard enough on this that it should move. Any more force and I think I'll cause damage to the part or myself. I'd like to know what's inside. BTW, my 63 Plymouth manual shows an exploded view of a non-tach drive cast body AutoLite dual point used in the 383HP police motors. I think I'd need either a C-body/300 manual or a Max Wedge supplement manual to see an exploded view of what's inside. Hopefully, either will have.
 
miller, hopefully Auto Lite or Prestolite or whoever the manufacturer's name really is, didn't add a snap ring inside behind that cup that looks like a reverse freeze plug.
Yessir, think your right...no snap ring. Yep, even a good breakdown drawing would help.
Do the shafts turn, including the drive gear?
Don't want to steer you wrong, but kinda thinking that reverse freeze plug needs to be pulled. I'd do some checking, for a replacement first!
Betting it's one of those deals...you go this way, I'll go that way, to get both drive and shaft out. Heck...it's all in fun, and games, right!
 
I've got the same distributor, but I've never tried to take it apart. I've gotta believe there has to be a gear on the main shaft, and a gear to drive the tach. The only way i see to engage /install that gear is thru that plug on the back side. I just dont know how to get it (the plug) out.
 
Don't think so. That slot should be the cable drive, cable end would have a key that fits into it.
Seal 'cup' on opposite end, might be how the tach drive shaft comes out.
Waiting, and watching...
Wonder if you could knock it out from drive side. Maybe OP could download a service manual at mymopae.com for a 1961 Chrysler 300G. It came with tach drive dist, I believe.
 
The main shaft has a gear on it. I take them out then you have to take the freeze out looking plug out. Get a new one because it will get damaged. Then it will pull out through that side. Let me see If I can find a exploded view of it.
 
Page 8-6 in the 1964 parts book has a good exploded view the service manual is illustration 8-27-18. Best I can do, wont copy for me, Do not hit it from the cable side you will damage the housing. I have seen them in police packages also in other years if it helps.
 
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About the only safe way to get that plug out, will be getting a small hole in the center.
Don't use a drill...don't know what's behind it!
A screw turned into the hole, and use the screw head, as a puller surface. Even so, it will be a hard one to get out.

Hold yer mouth right!
 
Exactly what I do. I found the caps on rock auto in the universal section, cooling. Forget the size been a while since I ordered one.
 
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This was answered on another forum, but you really do not need to remove it. Once shaft and bearing is out, you can clean that gear, and regrease it without removal. The few I have done worked fine that way. Of course I have a good clean tank to work with, which makes it easier.
 
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