Removing fan housing nut off generator

.............I removed one about a month ago with a pneumatic impact wrench. It took all of about three seconds.

Echo-ing Tim's sentiments, you can probably take the assembly down to your local tire shop (with the socket) and they'll zip it off for you in a jiffy. A six-pack makes a good payment for such services.

install the inner half of the (later model) pulley, tighten it down as good as you can (normal tightness that is). Then put the generator in a bench vice, held from the pulley hub.

The later model pulley has a huib that's shaped like this:

And thus it offers two nice, flat sides for the vice to grab hold of. The woodruff key between shaft and pulley hub will keep the shaft from turning. Now you can use a 36mm socket and an extension to slowly turn the big nut off. Do NOT take it to a shop to have them remove the big nut with an air impact gun. The shaft will break. (Happened to me.... Kidd might remember...)

If it still seems stuck, apply heat and penetrating oil rather than brute force. When it comes off it comes off rather easily, 2 foot cheater bar is plenty.

Jan

I knew I'd hear this suggested. :)

Jan

Small side question Jan, is there a trick to center the fan? I am having a really hard time trying to center one and just can't get rid of a vibration....

Don't know of any trick.. the hub should be self-centering, or in other words, offers only position. But because of teh warpy washer that goes between the fan and the nut, it's sometimes hard to keep them lined up and the fan slips off of the hub and gets to be tightened down wrong.

Jan

I just put my generator on a 4 x 4 block of wood lying on the ground so you dont put any pressure on the fan or fan tin. Put the 36mm socket on the fan pulley nut with a long wrench (I used an 18") and another long open end wrench on the shaft side (at least 12" or better) with the nut removed. Arrange the wrench on the shaft side so that it is pushing into the ground as you loosen the fan nut. Put your foot on the generator body or better yet have someone else hold it this way (don't crush the connectors or the tin) and you should be able to remove the nut easily with the rest of your weight on the 36mm socket.

Brett

I use a similar method, but I hold the gen-shaft with a leather strap oil filter removal tool tied around the gen pulley. This way you don't have to remove the gen pulley, which sometimes is stuck and is a bitch to get off.

Bill, '67 bug.

Air tools... Set the torque to low, direction to L, hold the fan with your hand, pull the trigger... You're done. Find a car repair shop with a bunch of greasy bikers working there, they'll probably do it for free. I bought a 1/2" drive high strength air-tool 36mm deep socket, before I had an air wrench.

Eduardo,

Is the problem that the generator needs to be pushed front/back, or move the fan shroud left/right/up/down? Check that the fan is assembled correctly to the generator.

Mike.

it does not self center in the shaft.... will have to take it out to recheck

the whole assembly...

Many replies suggested ways to remove the 36mm nut. An impact may loosen it but how are you going to torque it to spec? Placing the opposite end of the generator/alternator in a vise are cranking on the nut is a sure way to destroy the shaft, possibly rendering the core unrebuildable. And are you going to risk the shaft on your new unit reinstalling the nut to the proper spec of 40-47 ft lbs?

Look inside the fan. There are two dowel holes, one on each side of the big nut. This is meant for the factory wrench to leverage the fan while the 36mm nut is removed or tightened. These are fairly easy to make. If you don't have a welder, take the pieces to a shop. It's a small job.

I used a 2' piece of thick-walled tubing I had lying around. 7/8" I think but 3/4 or 1" would work as well. Since this wrench has to go inside the fan, the handle has to be bent 90 degrees. The easy way to do this with thicker tubing is to cut a 90 degree notch half way through and bend it in a vise. Weld it up later. You want to do this bend about 4" from one end so the tool will also work on the wider fans.

Next is the plate, 3/16 or 1/4" steel. Looking down on your fan, visualize a half-circle just small enough to fit inside the fan opening. The inside of this half-circle will need a smaller half-circle cut away to clear the 36mm nut and washers. So what you have is basically a half circle strip of steel 1 1/4" wide. Before you do the cutting, add a bit more to each end to give a little support for the dowels. Make the dowels out of a couple of old bolts that don't have threads all the way to the head. The diameter should be just small enough to fit in the fan dowel holes. If you don't have an old fan around to get the spacing of the dowels, cut out a piece of cardboard as a template and use your thumb pressure to get an imprint of the holes. Drill the plate and slip in the bolts. Mark and cut them so you wind up with 1" dowels sticking through. Weld the bolt heads to the plate and weld the handle onto the plate in the center at the 6 o-clock position. I added little mini-gussets, one to each side.

It took me about two hours and I used a jig-saw (sabre saw) to cut the steel 3/16" plate. Build one of these and all your VW buddies will want to borrow it.

I can almost visualize what you are saying but a picture is worth a 1000 words. Can you post a link to a picture of this fan tool?

Thanks Mike Cross

Photos of progress are located at:

I'm interested too.

Here's what I've pictured from Raymond's description:

-- Scott

"Mike Cross" wrote

On Sun, 18 Jan 2004 04:03:17 GMT, "Scott H" ran around screaming and yelling:

well I'm not Raymond(*everybody loves him?) but scott that is exactly what he is describing.....handy, dandy tool.... J

Damn! That's a whole lot better than my cheesy GIF:

And you even got the gussets in !!

P.S. Pleez e-mail me how you made the pic. Speedy Jim

I would also like to know what you used to draw the picture. It sure looks good.

Mike Cross

Photos of progress are located at:

Thanks guys. I used AutoCAD 2002 cad software to draw that. I drew it as a solid model, then rendered it to a bitmap file and then converted it to a .JPG file so that the file size was not so big.

-- Scott

"Mike Cross" wrote