Hi guys,

After I threw my second alternator belt I decided to investigate a bit deeper and discovered that the pulley is cracked. See pic.

Is it practical/possible to replace just the pulley with the alt in the car? I guess I'd need a point of leverage to hold the pulley still while breaking the nut. Or...is it better to bite the bullet and remove the alternator and repair on the bench? I suppose the third option would be to replace the entire alternator "while I'm in there".

Thoughts/advice?

Thanks!

Ian

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Pull I out. It's not that hard to do. The pulpy needs to be pressed on straight so there's no wobble or you'll just throw the belt again.

Thanks Billy. Figured it would be easier out of the car. Does the pulley need to be pressed on? I thought it was just held by a nut and woodruff key...

Yes. Pulley has a keeway. Never pressed one on and never had a problem throwing belts. The nut will pull it on straight

Wow, never seen that happen

Most new or rebuilt alternators don't come with a pulley, so you'll need to source one somewhere.

Guy over on theSamba is selling NOS one's for $35. Look under 411/412 parts.

Thanks for the tip! Just emailed him....

Here's the link in case anyone else needs...

https://www.thesamba.com/vw/classifieds/det....php?id=1717422

It looks like the pulley was cracked for some time. Notice the discoloration and rust where it broke.

good eye. looks like it started at the edge. Prob a combination of harmonics and stress caused it to spread and give way. I'm pretty sure my car wasn't driven much for a long time before I bought it in March of this year (just maintained and kept in a dry place). Now that it's back out on the road regularly the weak points are showing up. I hope that's the last of 'em...

That belt is the wrong section,looks to have stressed a weak pulley,never seen one break like that,looks rather thin @ the point where it broke

The sight line to do the pulley in the car is terrible.
To remove the alternator is even more terrible.
Get a very big pair of channellocks to hold the pulley.
Or, a large screwdriver with a square shaft can used in the notches of the pulley to act as a stop.
First step is to remove the engine lid.
Second, make appt. with chiropractor

It sits too high in the pulley.

The belt just ended up there when I was feeling around to see what was up. Thanks for the tip Rory! I'll start taking Advil now....

It looks to have broken in between two of the notches if I'm seeing it correctly (one of the notches is circled at 6:30 the other is at 2:30)

Ian, I did mine the weekend you showed up at Mort's; it's no fun. I had the advantage of having the heat exchanger off, which provides as much access as possible.

Get it upon your lift and have at it, send the unit out for a refresh so you won't need to go back in that dark hole again...

It's not uncommon for the pulley to be stuck on the shaft. If you can replace the pulley in the car, count yourself lucky. But if it sticks, just stop and pull the entire alternator.

Thanks guys. Gonna try to take off the short tin around the alternator and hopefully replace the pulley in the car. Wish me luck!

Ok. Mission accomplished.

Because there isn't enough space between the firewall and the alternator to fit an impact wrench on the nut, I ended up just biting the bullet and removing the alternator. Really not too bad. Here's what I did and few pics if anyone else finds themselves in this situation.

– First I removed the short piece of tin under the alternator (several cheese heads). I also needed to loosen the heater blower motor to get the piece out.

– Next I took the left J-tube and the ducting out to gain access to the bottom alternator pivot bolt nut. Then removed the cheeseheads and 10mm bolt holding the front alternator plate.

– Unplugged the alternator harness from the board, removed the eye terminal from the starter and pulled the grommet out of the tin. Disconnected the cooling boot.

The alternator came out pretty easily. Check out the damaged pulley. Pretty crazy. Once I had it off I noticed that there were two other stress cracks on it. Could these be from age? Or some other stressor?

Anyway...I'm going to try one of the Contitech Belts McMark, recommends and finally get back on the road.

Thanks for the help!

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Put one of the conti-tech 10 X 965 belts in. Perfect fit, just as mcmark said....

First, on the old pulley...

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And in the car...

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