Alternator rotor: chewed up threads

[Anonymous]

Hi, I'm still trying to remove the alternator rotor from my GS750. I bought a rotor/magneto puller from DK, but all it did was chew up my threads, and all it is is a very large bolt. My question is, is there another, easier way to remove this damn thing. I've tried everything from cursing at it, and insulting it to hitting it with a BFH. Nothing seems to work and I really want to change it out for this season, which is starting soon I hope. (today it got near 55) PLEASE HELP! Should I just re-tap and try again or is there a better way!

[argonsagas]

I have not removed one yet, but will likely do so shortly,as I think I have a broken tooth on mine.

I looked at it last year while the stator was out, and was expecting to have to repair the starter clutch. (This was before the tooth concern)

I could see no easy way to do it. There were two holes, but I could not see how much use they would be as only two means the puller tends to slip to one side, and defeat the exercise.

Heat is an old stand-by, but you take a chance with distorting the metal, and that causes balance problems. Suggest you not do that unless you plan to toss the old one.

What I expect to do is drill three evenly-spaced holes in the rotor, in a triangular pattern, each the exact same distance from the centre.

Each will be threaded and then I plan to use a balancer puller, pressing the puller bolt against the shaft.

Rather than use heat on the rotor, I hope to pack the shaft in dry ice for a few seconds before applying the torque.


Additional note.......since metal filings are extremely harmful, I plan to use a shop vacuum, with the wide nozzle wired to fit directly underneath the point being drilled, and a piece of wide tape against the rotor, so nothing can fall between.

You should do something like that when tapping the metal as well, for the sme reason.

[Carter Turk]

Alternator rotor

When you speak of chewed up threads, are you talking about the one on the rotor itself or the threads on the end of the crankshaft?

I've broken 9 starter clutch bolts off in the past year, so I've had my rotor off a few times on my 1150.

The puller is pretty straight forward, thread on till bottomed on the rotor, hold with appropriate wrench, use socket on the smaller bolt and start turning.

After that it should slip off easily.

Did you happen to cross thread the puller on the threads? If so you may have to find an expensive die to rethread it. I don't know if the threads are run of the mill metric or not.

If you have time, maybe discuss in more detail the threads in question and what the puller you have looks like.

Carter Turk

[Carter Turk]

Alternator rotor

I read the first response to your post again and came to the conclusion that you're having trouble removing the nut off the end of the crankshaft?

If this is the case, and no air tools are available, you can take a 4''-6'' opening tri-clamp, like a c-clamp, but has three spots to apply pressure.

Find a piece of angle iron or aluminum (shape of an L) that is long enough to touch the garage floor from the top of rotor. Hack saw off the tri-clamp on both sides of the center threader so that the two remaining threaders are on the top and bottom of the remaining c-clamp. Discard middle threader.

Measure the rotor diameter and mount the remaining tri-clamp halfs about 1/8th of an inch wider than the diameter of the rotor. Mount each half with two screws and bolts each to the to the angle iron. Hack off swivel tips on the the remaining threaders.

Locate the two holes on the outside of the rotor. Thread threaders in just enough so that they are not pressuring the magnet inside the rotor. Locate the angle iron so that the iron is pressuring the floor at about 7:00 oclock for loosening. You may have to rotate the crankshaft to align the holes to achieve this.

Use a breaker bar on the socket wrench and reef away.

This may or may not sound complicated but cost less than 10 bucks to make and should only take a half hour or so to make.

I have successfully used this tool 6 times to remove and remount my rotor to the proper torque specs in the comfort of my cold garage. Carter

[Anonymous]

Threads:

The threads in question are the threads inside the rotor, and the puller is a 16mm X 1.5 RH thread BOLT. Just a bolt, not a real puller (this is what confused me) The way I figured it working is threading it through the rotor until it bottoms out on the end of the crank and then continuing to thread until it pushes against the end of the crank and pushes the rotor off. This is also the way the tech thought it might work, due to the fact that we have pressed-together cranks, thus a slidehammer is a really bad idea. so, the threads are in the center of the rotor, and they seem to be pretty chewed up. I tried to find a tap, but I can't find one that is 16X1.5 RH, this is not exactly standard. I do not want to junk the rotor that comes off, what I am doing is putting the 750 rotor/stator on the 1000 due to the fact that I do not need output as high as the 1000 is, I want to reduce rotating mass, and the frame the 1000 is in is a 750 frame and the wiring doesn't match up exactly. For now I think I figured it out, I ended up taping off 2 wires that were meant to go to the regulator (I have an aftermarket reg/rect so I only need 3 wires, not 5) and taped off 2 wires on the bike side that came from the regulator. I know its atleast kind of charging now, because the battery is shot, but I could jump it and once it was running I could take the cables off and it stayed running, full power, bright headlamp.