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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: belfert on September 12, 2020, 04:18:44 PM

Title: What torque specs for pulley nut on 50DN alternator?
Post by: belfert on September 12, 2020, 04:18:44 PM
Does anyone know the torque specs for the pulley nut on a 50DN alternator?  I can't find any official Delco Remy documents that state the torque values for the nut.  I watched a Youtube video where someone mentioned it should be 250 ft lbs.  That seems really high to me.  I have a torque wrench that will do 250 ft lbs, but I don't want to break the nut or something else by tightening it too tight.
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: Van on September 12, 2020, 04:28:36 PM
About 215lbs, I've done em" using an Air impact before with no problems YMMV ;)


http://www.delcoremy.com/documents/alternator-instruction-sheets/drive-end-frame-and-seal-upgrade-package-kit-istal.aspx
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: belfert on September 12, 2020, 04:51:48 PM
How do you keep the pulley from rotating while applying 215 ft lbs of torque?  I saw a video that showed using a strap wrench to keep an oil seal installer from rotating when putting a new seal in a 50DN, but can a strap wrench handle 215 ft lb?  I guess I can try it right now and see.
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: Van on September 12, 2020, 04:58:01 PM
Strap wrench would be best, use a cheater pipe on it for more leverage if you are doing this by yourself. If on the floor straddling the monster might help.

edit: If you have the room re-mount the 50DN then strap the pulley.
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: belfert on September 12, 2020, 05:34:22 PM
The strap wrench worked just fine once I had the strap wrench on the pulley the right direction.  I had no idea a cheap Husky strap wrench could handle that much torque.  I already had the alternator mounted in the bus.  I used my Makita 3/4" battery impact to tighten it.

Thanks for the help.  I started it up and everything seems to be working.  What size is the right size socket for the pulley nut?  1-5/16" socket was quite loose.  I took the new nut to Menards and a 33mm socket fit fine.  I used the 33mm socket, but everyone says 1-5/16" is the size.

I need to run out and pick up all the tools before it gets totally dark.
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: Van on September 12, 2020, 06:28:40 PM
Good deal!
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: DoubleEagle on September 12, 2020, 07:54:27 PM
33mm and 1 5/16" are virtually the same, the 1 5/16" might have some wear.
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: belfert on September 13, 2020, 04:38:09 AM
The sockets were brand new as I had just purchased them from Menards as I had no sockets that large.
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: richard5933 on September 13, 2020, 04:43:30 AM
Quote from: belfert on September 13, 2020, 04:38:09 AM
The sockets were brand new as I had just purchased them from Menards as I had no sockets that large.

Could be a problem with the socket itself. I've found that the tools I'm buying recently are not true to size, with some open-end wrenches in my drawer being tossed out due to not fitting the size they were marked. Either too tight or too loose, but not right.

Maybe it's necessary to take calipers to the store nowadays to do some QC before buying tools?
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: belfert on September 13, 2020, 06:29:33 AM
Quote from: richard5933 on September 13, 2020, 04:43:30 AM
Could be a problem with the socket itself. I've found that the tools I'm buying recently are not true to size, with some open-end wrenches in my drawer being tossed out due to not fitting the size they were marked. Either too tight or too loose, but not right.

Maybe it's necessary to take calipers to the store nowadays to do some QC before buying tools?

That could be.  I bought a combination wrench from Home Depot several years ago that was way out of spec.  It caused me to buy a set of American combination wrenches instead, but I had to wait a week to get them.

Menards was a leader in still having USA made sockets and wrenches on the shelves, but the American factory they got the product from closed down.  They switched everything to China maybe two years ago.  The 3/4" drive 33mm socket I got seemed expensive for a Chinese socket at $18.  (They didn't have that size in 1/2" drive and I have a 3/4" impact.)
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: chessie4905 on September 13, 2020, 07:38:27 AM
Ive had to buy the "inbetween" sizes, because the 3/4 drive set skips sizes after 1" or so. Amazing how many times I needed 1 5/16 and other sizes I didn't have. I have been filling in missing needed ones, through Ebay or Amazon. Got a real steal on 3/4 drive impact sockets when a company went out. Only problem is that the missing sizes cost as much as the whole set cost. May never replace those unless sorely needed.
Title: Re: What torque specs for pulley nut on 50DN alternator?
Post by: DoubleEagle on September 13, 2020, 08:39:57 AM
There are still quality impact sockets out there like Wright Tool, but they cost big bucks. The best compromise is to find them at garage sales and estate auctions. Most of my best tools were found that way. Government surplus auctions have new unused sets at rare times. Being forced to buy a single piece quickly because it is needed badly is the most expensive way.