Help: Removing swedged weights on Model B crankshaft

Dave in MN

Dave in MN

Well-known member
I need to remove the swedged weights from two Model B crankshafts prior to sending them to the crank grinder. Anyone have the set-up info to drill out the dowels? I saw a diagram some time ago that refrenced the angle of the dowel to the centerline of the main bearings.
Thanks in advance for any help provided.
See the photos below....
 

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A friend of mine is a welder, he welds a 1/4" nut to the pins (the pins only) and pulls them with vice grips. It usually takes him 3 or 4 tries to get them out. He also does not remove the weights entirely from the crank. He slides them over enough to grind the throws, has them ground, then slides them back in place and has the mains ground. This may or may not work for you?
 
Jim's method works pretty good for original pins but all the BB cranks I have had were not original and had spring pins or sometimes called roll pins installed.
These are quite brittle and can be sheared off by applying a lead hammer to the counterweight.
One crank I had came in with the pins welded over. You don't want to hear about fixing that one.
 
Thanks guys. I will try the "weld a nut on it " method where the pins have not been messed with. If I get one or more out, I will have my drilling angle for the abused pins. Some are drilled out half way and the drill angle is different in each hole. I'll post back and let you know how it went.
 
Many years ago I saw a shop drill, thread the pins, insert grade 8 bolts and pull with a slide hammer. You still would have to know the pin angle. That I can't find.
 
I was able to drill all the pins out. I discovered that the pins aim straight to the centerline of the main journal. I thought they were off center a few degrees from a sketch I saw a couple years ago. The pins are about 3/16" in diameter. Once drilled out, Pete's suggestion of using a lead hammer slid the weights enough to allow for grinding.
They are both ready to go to the crankshaft grinder. Thanks guys!

SIDE NOTE: As I was drilling the peened portion of the crankshaft holding the pin in place, the drill bit hit the top of the pin and it started down into the pin a fraction of an inch and the pin started to turn. I put a bit more pressure on it with the Bridgeport and then backed the drill bit out. The pin was stuck to the end of the drill bit and it pulled right out. The angle of the pin through the counterweight and into the crankshaft was easy to determine after that stroke of luck.
Good Day!
 
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Dave in MN said:
I was able to drill all the pins out. I discovered that the pins aim straight to the centerline of the main journal. I thought they were off center a few degrees from a sketch I saw a couple years ago. The pins are about 3/16" in diameter. Once drilled out, Pete's suggestion of using a lead hammer slid the weights enough to allow for grinding.
They are both ready to go to the crankshaft grinder. Thanks guys!
Good Day!
Click to expand...

Only one small problem with just moving the weights and not taking them off.
The crank grinder guy will have to move them back to grind the mains and he may want more money for that.
 
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