Fan belt pully shims

[lhoudyshell]

For some reason my fan belt became real loose on my 68 912, after several years of being just fine. I pulled off the outer pully, belt and adjusting shims. Behind those adjusting shims were 5 large round shims. I reasoned that the large round ones should be divided up front and rear with the adjusting shims in between. I replaced the pully, tightened the nut got the belt tension right, my question is: right, wrong, or? The manual does not talk about the large round shims, only the smaller notched ones. Car runs OK, but is there something I don't know? Thanks Lynn

[WFBowen]

Lynn:
I've only had notched washers on my cars - maybe some 911 washers found their way in there. Here's a pic from a repair manual:


Bill.

[lhoudyshell]

Bill, I dunno, thanks for the idea. Not sure if I should get rid of the large round shims, or? There is/was a reason someone put those on there. Are those larger round shims possibly 911 ones. I have not seen those. I still have 6 of the notched regular shims. Lynn

[WFBowen]

Lynn:
The 'by the book' way is to use enough shims between the pulleys to obtain the proper belt tension - more shims loosen/fewer tighten the belt. All extra shims are stored between the outside pulley and the big nut. In the real world with cars approaching 40 years of age, however, things might need a little McGivering. Something (inner pulley &/or the pulley hub on the gen. shaft) might have worn to the point where some extra spacing was needed. My take on this is to try the correct way (aircooled VW shims work) if possible. If not, since the car worked with the round shims, etc., you can most likely keep using them. Just double check: 1. that you're getting belt tension with shims and snug pulleys, vs. just cranking on the big nut. 2. look straight down on the belt and check that it seems proper aligned with the crankshaft pulley.
Good luck,
Bill.

[lhoudyshell]

Bill good advice, I failed to say the generator and pulley halfs are relatively new less than 2000 miles, with no tinkering in the interm. I have looked down the belt just now as you suggest and appears to line up. I suspect the mechanic may have used a bit wider belt than is called for, so extra not standard shims were used to get the belt to seat. I have ordered a new belt and a few extra shims. When those arrive will have another go at it. I think you are right, will try the standard way. In the meantime I drove it to coffee this am and all worked just jim dandy. I would ask the mechanic, but doubt after three years he would remember. Needless to say as much as I like this car all original except for a respray 20 years ago, it does'nt get a lot of use. I am now learning about the 79 SC recently purchased. Many thanks for your thoughtful comments. There are not too many of us 912 drivers out there. Lynn, Boise