Generator Shims

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Steve Douglas
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Generator Shims

#1 Post by Steve Douglas » Sat Nov 23, 2019 10:20 pm

Question: what is correct OD of the shims to be used on the pulley end? I had two generators to change. My friends 58 Cab had a VW generator that the bearings were shot on. and, My 59 coupe had a 160 watt generator and I wanted to replace it with a fresh 200 watt. Since both cars were being done one after the other I made notes of what was different. Mostly the collection of shims for setting the pulley spacing. I laid out all of the different shims and took this photo, I have 40mm OD, 42mm OD with two holes, 42.5mm OD, and 46mm OD. Then for the fan end, (the same for both cars) a thick 46mm OD with squared inside, a thin 47mm w/round hole, and 46mm wavy washer. Neither car had all 10 shims with the same OD. I found 20 of the 40mm OD shims and assembled both with those. But have about 49 more of the various sizes. Since I have changed generators on 30-36hp VWs as well as a few 356s it could be a mix from those.
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David Jones
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Re: Generator Shims

#2 Post by David Jones » Sat Nov 23, 2019 10:31 pm

I doubt the generator cares about the OD just use 10 and get the alignment and tension correct.
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Steve Douglas
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Re: Generator Shims

#3 Post by Steve Douglas » Sat Nov 23, 2019 10:47 pm

David, I think you are right. The larger diameter shims, 46mm, might give more support to the pulley halves. But, I only had 9 of those in my collection . 4mm isn't all that much more. Could the belt actually ride on the larger shims?

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Ron LaDow
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Re: Generator Shims

#4 Post by Ron LaDow » Sat Nov 23, 2019 10:47 pm

Don't have a generator pulley in front of me, but don't the inner halves have a recess for the shims?
If so, it'll tell you the max OD.
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David Jones
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Re: Generator Shims

#5 Post by David Jones » Sat Nov 23, 2019 11:08 pm

No recess for the shims they have to sit there all day. No way the belt could get near the shims as they are well inside the Vee of the flange where the belt sits. Are you thinking of a recess between the inner half and the generator collet Ron as that is where you may add a shim to move the pulley out to perhaps correct a misalignment.
If I had known I would live this long I would have pushed the envelope a little harder.
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Steve Douglas
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Re: Generator Shims

#6 Post by Steve Douglas » Sat Nov 23, 2019 11:11 pm

Ron, I went out and measured the recessed areas of the inner and outer pulley halves. The inner half has the recess that fits the hub, and it's 44mm ID. The other half has a recess for the shims on the outside and is 47-48mm, so any shim that I have with the square hole will fit.
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David Seeland
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Re: Generator Shims

#7 Post by David Seeland » Sun Dec 01, 2019 5:03 am

My 2 piece case 1500S engine 40015 has generator shims 45mm diameter x 1.5 mm (8) and one 45mm x 1.0 mm shim.
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Steve Douglas
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Re: Generator Shims

#8 Post by Steve Douglas » Sun Dec 01, 2019 12:35 pm

Hi Dave, haven't seen you posting for a long time, good to know you are still around. I think the larger shims 45-46mm were from some of my 30-36hp VWs, not sure where the one with the 2 holes came from.

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Re: Generator Shims

#9 Post by Al Zim » Tue Dec 03, 2019 11:18 am

WATCH YOURSELF! Why would someone make a shim that is larger in diameter than the factory shim? We know the factory shim worked on thousands of Porsche's and hundred's of thousands of VW. It is my guess that someone found a cheap circular piece of metal the thickness of the Porsche/VW shim and all they had to do was cut the hole in the middle. Each of your other larger shims are used on the fan end of the generator. 75 Foot Pounds of torque is the requirement for the fan nut. al zim
 

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