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| | | | Joined: Aug 2000 Posts: 1,438 'Bolter | | 'Bolter Joined: Aug 2000 Posts: 1,438 | Well, dang. I buggered up the threads trying to get the pulley nut on. Does anyone know the thread size so I can get a tap and die set?
Dennis
40 Chevy 1/2 ton
| | | | | Joined: Mar 2014 Posts: 4,473 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,473 | As I recall it is a 16 x 1 metric. Find a metric thread size gauge to check me on that. Good luck...not an easy re-threading job.
~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
| | | | | Joined: Mar 2014 Posts: 4,473 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,473 | If I'm right on the size, get a split die like this one: https://www.globalindustrial.com/p/...adjustable-die-fine-thread-1-1-2-inch-odThat way you can start at the end closest to the alternator, tighten the die and work it backwards to the distal tip of the shaft. Then just buy a new nut.
~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
| | | | | Joined: May 2015 Posts: 10,997 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 10,997 | Might be able to use a thread file, or just a triangular file, if just the first few threads are buggered up. If you can get the nut started straight, you'll probably be OK.
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: May 2015 Posts: 10,997 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 10,997 | I'm not sure you could get that adjustable die over the threads, even if stretched out all the way. You could cut the nut in half and clamp it on the alternator end and unscrew it to clean up the threads a bit. Of course you'd need a new nut. I think it was 59fleet that came up with that idea for wheel studs. 
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: Feb 2004 Posts: 29,740 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,740 | Once you determine what the thread diameter and pitch is, find a hex die that size, cut the die in half and use a socket to back it off of the shaft. You'll trash a die but you'll save the alternator armature.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Sep 2011 Posts: 1,451 'Bolter | | 'Bolter Joined: Sep 2011 Posts: 1,451 | Might be able to use a thread file, or just a triangular file, if just the first few threads are buggered up. If you can get the nut started straight, you'll probably be OK. Thread pitch gauges & thread file.
BC
1960 Chevy C10 driver 261 T5 4.10 dana 44 power loc
1949 GMC 250 project in waiting
1960 C60 pasture art
Retired GM dealer tech. 1980 - 2022
| | | | | Joined: Aug 2000 Posts: 1,438 'Bolter | | 'Bolter Joined: Aug 2000 Posts: 1,438 | Thanks, that gives me some options. I've sent off for a thread pitch gauge. Needed one for a long time anyway.
Dennis
40 Chevy 1/2 ton
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Most hardware stores have a thread pitch gauge placed somewhere near bolts!
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Dec 2018 Posts: 2,450 'Bolter | | 'Bolter Joined: Dec 2018 Posts: 2,450 | Dennis m That thread has been the same for decades,unless its demolished should be able to file off the burrs. | | | | | Joined: Dec 2018 Posts: 2,450 'Bolter | | 'Bolter Joined: Dec 2018 Posts: 2,450 | Dennism In another life when I was an alternator rebuilder we had a die to chase "core barrel" bites off of those shafts. | | |
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