Late to the game here (haven't read entire thread): the generator pulley in the last photo is a VW part. It is a larger diameter than the stock 912 pulley so the 'extra' 5mm shouldn't be a surprise. It also means that the generator/fan are not spinning as fast as they would if the correct pulley was mounted. And yes, the hub is trashed (usually from not running enough shims). Belt should run in the crank pulley groove nearest the motor (outer pulley was for air pump - MY68 only).

Because of other factors, you may encounter pulley alignment issues: if someone mounted a VW pulley, there could be kludges to 'attempt' alignment, including improper/improper assembly of 'pie plates' (sheet metal that bolts to fan shroud).

BTW, 8 shims are minimum for 912 generator pulleys; I run 10 to ensure nut is doing its job.

Peter

Hi

Thanks for this info, it has been very helpful.

I must say i've no idea what I've dug myself into with this car. It seems much more complex than anything I've ever owned or worked on. So with no familiarity with this type of engine setup, I don't feel too confident messing around with it (I tend to take the safe road, when I don't know, I ask)

So, bearing in mind the generator seems up to the job after a successful polarizing session, i'm now down to check what's required to get it back to spec ?

- new hub (thank god, i had no idea this was a detachable part, for example)

- new inner and outer half pulleys, Porsche spec

- a set of washers (the ones with the round inner diamer cutout), those I have already

New battery is to be bought, but would this generator repair, by any chance, giving the correct generator rotational speed, help assist in solving the charge light coming on, since it wouldn't be underdriven ?

This may all help with generator light issue as long as the battery, regulator and generator (electrical properties) are up to snuff.

Having just gone through the 'purchase' exercise:

OEM Pulley Hub - 547.09.304: $25.64 (Stoddard - no offense to our host intended)
Inner Pulley Half - 539.09.315.M260: $14.75 (host)
Outer Pulley Half - 539.09.316.M260: $14.50 (host)

Since I have nuts/shims I did not purchase (but had yellow zinc plated). The correct shims have the two flats on the inner diameter to match the hub. I have attached a photo of generator hardware (labeled) I recently had plated.

Peter

http://forums.pelicanparts.com/uploa...1469976008.jpg

Thanks, all very clear. I will make the purchases, i have a couple of things needed elsewhere on the car.

The regulator is new, less than 300 miles on it, so if the generator has shown signs of working and i get a new battery, hopefully I should be able to enjoy a decent running car soon.

Ivory, I'm pulling for you to sort it out.
I have a 68 that was having charging issues and after reading here, and other forums, I bought the alternator conversion. I just don't want to hassle with the more "sensitive" generator, and I have the smaller diameter gen to make matters even more complicated.
I did the alt conversion on a type I years ago and never had charging issues again, so that made the 912 alt conversion a no brainer.
Of course, I haven't installed it yet so hopefully I didn't just jinx myself :D

It's proving excessively hard to get the hub and inner pulley hakf off the generator shaft, it just doesn't want to budge. Am I missing anything ? I can actually reverse the car by holding onto either side of the pulley

Since the hub has a key I would have thought it would just slip on and off, then secured by the nut, but it's quite stuck on.

Amazed at how cheaply these cars were designed, I'm beginning to wonder if it's worth the effort.

Looking back at Post #19, there is quite a bit of rust which can effectively 'weld' parts together. Use a 'rust treatment' like PB Blaster over several days. Drill a small 'relief cup' in the center of the generator shaft (see photo). Mount and tighten a two-jaw puller using the relief cup to hold the center screw. Once everything is in place, whack the center screw head with a BF hammer. If the assembly does not 'explode' apart in a couple of attempts, heat the pulley hub with an oxy-acetylene flame (lots of heat, small dwell time - you don't want heat traveling into the generator) and repeat. If you don't want to mess with it, take the assembly to an automotive machine shop.

Peter

http://forums.pelicanparts.com/uploa...1470580619.jpg

I'm sure this is answered elsewhere, but I can't find it. Should my 1968 Porsche 912 keep running if I disconnect the battery? I ahe voltage at generator, and my RED light goes out after the engine starts, but I almost feel like my 912 is running solely on the battery. Thanks in advance.

If it is supposed to keep running, what are the usual culprits?