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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Emcemv on August 16, 2014, 06:12:23 PM

Title: Fan Drive pillow block shaft
Post by: Emcemv on August 16, 2014, 06:12:23 PM
Some of you may remember my post a few months back about how my fan drive shaft had been spinning in the bearing and the race had worn a 1/8" deep groove in the shaft.  My MC-7 is a combo and has the scenic side radiator so has the fan driven through a right angle drive and the shaft sits in a pillow block with 2 big ball bearings.  Since the shaft was pretty much not available anywhere, I had the old shaft welded up and re-turned to make it new again.  At the time many of you cautioned that the welding would warp the shaft and it did but the machining was able to take care of it, it only warped about .003".  So I got it back yesterday and it looks beautiful and I got it back together today....$45.00 for the welding and a freebie from a machinist friend.  Here's some photos
Title: Re: Fan Drive pillow block shaft
Post by: wildbob24 on August 16, 2014, 06:41:53 PM
Nicely done!

Bob
Title: Re: Fan Drive pillow block shaft
Post by: luvrbus on August 16, 2014, 07:09:39 PM
Very nice job that is the way I am doing the obsolete S cams on some Eagles
Title: Re: Fan Drive pillow block shaft
Post by: eagle19952 on August 16, 2014, 07:15:07 PM
you found an excellent welder, had you not we'd be looking at a paper weight.
happy you took the leap..... ;D
Title: Re: Fan Drive pillow block shaft
Post by: Emcemv on August 16, 2014, 07:47:43 PM
To Weld it, he chucked it in a lathe and turned it at real slow speed and welded as it rotated, I think that kept the heat pretty even and cut down on the warping.  Bearings were a slight press fit and we used red locktite on them as well.  I think this all started because there was a spacer missing, there was nothing to hold the shaft in place on its length so once it started to move, it just got worse and worse.  Now I have a spacer made to locate the pulley and prevent the shaft from moving in and out.
Title: Re: Fan Drive pillow block shaft
Post by: eagle19952 on August 16, 2014, 07:52:01 PM
Quote from: Emcemv on August 16, 2014, 07:47:43 PM
  I think this all started because there was a spacer missing, there was nothing to hold the shaft in place on its length so once it started to move, it just got worse and worse.  Now I have a spacer made to locate the pulley and prevent the shaft from moving in and out.

sounds like you solved it....often no one asks/solves why long enough to fix the cause.
Title: Re: Fan Drive pillow block shaft
Post by: luvrbus on August 16, 2014, 07:55:48 PM
The guy that does my S Cams uses a Arc spray process it works good
Title: Re: Fan Drive pillow block shaft
Post by: brmax on August 16, 2014, 08:06:04 PM
That's a great job and better yet to have the good friends.
Is that Spray process actually have a powder type metal they use with welding
Title: Re: Fan Drive pillow block shaft
Post by: Lee Bradley on August 17, 2014, 01:18:18 PM
A little late now but if you go to a crankshaft shop they are set up for welding and turning shafts to thousandths of an inch.
Title: Re: Fan Drive pillow block shaft
Post by: luvrbus on August 17, 2014, 03:20:23 PM
A automotive machine shop does my S cams the same process they use on cranks