Is there any significance to the slight variations in the pulley hubs? The one off our T5 Super 90 is damaged enough that I am planning to replace it. In looking for a replacement, I noticed some minor differences.
In the center, ours has a notch on both ends of the opening. Others have a groove that goes from end to end.
On the exterior ours has raised middle with flat shallower edges. Others seem to have grooves.
PulleyHubOriginal.JPG (67.36 KiB) Viewed 1409 times
s-l1600-4.jpg (68.43 KiB) Viewed 1409 times
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S
Regarding the red oval around the upper center marked "notch". The photo is good. I think I see a rectangular key stuck in the keyway. That is a little wierd. My recollection is that the key is a half moon shape and that it is inserted into a half moon shaped slot in the surface of the shaft of the generator. The pulley hub slides on over the generator shaft and the previously inserted key.
I like the hub on the bottom. What are identified as grooves are indeed groves. They are a side effect of the way the flat surfaces on the sides of the pulley hub were generated. Clearly the plane defined by the hub flange (that clamps the pulley spacer washers) is still a plane. The grooves do not reduce the strength of the hub flange in any important way.
The broached keyway slot in the inside diameter of the hub is entirely appropriate. It slides over the previously installed half moon key mentioned above.
Robert Vaughan wrote: ↑Sun Jun 23, 2019 5:15 pm
I think I see a rectangular key stuck in the keyway. That is a little wierd. My recollection is that the key is a half moon shape and that it is inserted into a half moon shaped slot in the surface of the shaft of the generator. The pulley hub slides on over the generator shaft and the previously inserted key.
Right you are Robert. I wasn't expecting a flat key in the groove. A couple taps with a hammer and it popped right out. Revealing a groove all the way through. i wonder if I have a moon shaped key that was sheared off. Need to check on that now. Thanks.
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S
The woodruff key is supposed to fit snugly into the shaft's slot and the hub easily slides onto the shaft.
The second photo looks like the side flats were milled to suit the flats of the shim bores, but the 3rd photo shows extra milling was done to make sure there's no rounded or radiused corners prohibiting the shims not
fitting flat to the the hub's flat sides; I've never seen those groves on any hubs I've used during my years.
Robert Vaughan wrote: ↑Sun Jun 23, 2019 5:15 pm
I think I see a rectangular key stuck in the keyway. That is a little wierd. My recollection is that the key is a half moon shape and that it is inserted into a half moon shaped slot in the surface of the shaft of the generator. The pulley hub slides on over the generator shaft and the previously inserted key.
Right you are Robert. I wasn't expecting a flat key in the groove. A couple taps with a hammer and it popped right out. Revealing a groove all the way through. i wonder if I have a moon shaped key that was sheared off. Need to check on that now. Thanks.
You had a sheared key because some dummy put the hub in a vice to torque the fan nut. One well=known poster recommends that; DON'T DO IT !
I believe the pulley hub originated with the first VW's. It was used by VW into the early 50's until they cam up with a pulley that was easier to install since the hub and the inside of the pulley were welded together and cheap round shims could be used with a standard manufactured rather than a machined nut. I have put together a lot of generators and always tightened the blower with a new wood-ruff key
a good hub. Look the torque up in the shop manual and use a calibrated torque wrench. al zim Zim's autotechnik 800.356.2964 If you have a question call
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