MGB & GT Forum

Hello friends,

Am I missing something?

I have sent these questions off to Moss customer service as well. Not sure if they are open due to the holiday?

The thrust bushings are the same. It seems like the shaft on the new one sticks out too far. As a result the wilson key slot is too far away from the edge of the bushing. The fan has a key slot and it is not engaged with the key on the new one. The fan is too close to the housing. It will bottom out or not spin with the pully. If the thrust washer was longer, it would work. The old alternator pictured shows the washer reaching the end of the keyway.

Like I asked, what am I missing?

Thank you in advance,
Josh

Moss is probably closed today (MLK Day). E-mail isn't the best way to contact them. They may or may not respond quickly.

Call them tomorrow with your concerns and questions.

---

“Ideological certainty easily degenerates into an insistence upon ignorance". Daniel Patrick Moynihan

In any debate, the side which strays from civil discussion is usually the side that lacks confidence in its debate position or in the merit of their arguments. Making personal attacks on the opponents instead of staying on the subject is also a sign of weakness.

Anyone who feels compelled to respond in kind to any perceived slight is often suffering from narcissism.

The catalog mentions a 1/2" connector on page 83, p/n: 161-525. There is no image available. It is listed under the re-built alternator 1974-1/2 - '78.

I wonder if I need that for a new 130-100 alternator on a 1979?

I happen to have some G10 tubing of the correct diameter and thickness as the spacer that came with. Truly some kind of miracle! I sliced off a 1/8" piece and inserted it between the fan and the spacer. It looks perfect now!

I can probably get away with this for the rest of time. But, I am concerned that the alternator was not assembled correctly...

Yes, you'll need to add a small spacer at the base of the fan to allow it to clear the alternator housing. However, you should be able to remove your original bushing and install it on your new alternator. RAY

Thanks Ray.

I have two spacers. One for the old alternator and one for the new alternator. They are identical. They are each installed on the alternators in the pictures. If you look closely you will see a 2.5mm difference in the way they seat inside the housing. This is my problem. The new alternator has a deeper seat...

Blaine from Moss replied to my email. He said the fan is supposed to go past the key. That the pulley once fastened tight will clamp it in place. Does that actually make sense to anybody?

I tried that, and it does not work. The fan just rotates independently, or not at all.

I am pretty sure the key is supposed to connect the fan and pulley together so they spin in unison. That is how my old one worked.

I feel MOSS should provide these alternators, fan blade, pully & nut included. That's how I bought mine from a Belgian MOSS reseller on a parts fair a few years ago for €67,50.
IMO the shaft of the one you are having now indeed sits wrong; does the nut from your existing alternator fit to it?

The nut on my old alternator did not fit a 2nd hand one I had as intermediate solution, another reason to welcome this 17ACR alternator with all parts included I have now installed

PS I checked the MOSS Europe site: indeed all parts are listed separately by now.
I was lucky with my suppliers I guess, I still found them like this on my last Dutch parts fair, 8th of January. Prices have gone up slightly though



Edited 2 time(s). Last edit at 2017-01-17 10:03 AM by Donthuis.

Hi Don,

Thank you for your insight. I am happy to hear that I am not alone suspecting the shaft is seated at the wrong measurement, or location. The new Moss alternator came with a nut, washer, and wilson key. It does not include a new fan or pulley. The alternator was on sale for $92.99. I looked at their images of a new fan and a pulley. The new ones look very different from my old ones. A new set is an additional $47. There is no indication anywhere that my old ones for the same application would not work. It is hard to describe the new ones. I think the fan is stamped such that the middle is dished to reach the spacer. The pulley has a big step to gap the additional distance as well.

Sincerely,
Josh

When i purchased the same alternator from Moss, it came with the fan and pulley already mounted. You may be able to "double up" the two spacers to solve your conundrum. Check to see just how much the two spacers together move your pulley from the stock location. Then, use a grinding wheel to remove a bit of material a little at a time until everything is as original. Never a dull moment. RAY

If the shaft is actually in a different position relative to the alternator body, there is the possibility that something is amiss inside. Maybe a bearing wasn't pressed far enough onto the shaft or something like that. It may be worth taking some accurate measurements and asking Moss to verify against other samples.

Thanks for the advice and comments.

I used the G10 spacer that I made and installed the alternator yesterday. As per my previous comments... The metal spacer that came with was 3/8" long. I do have the old one and the new one, identical. I needed a 1/2" overall to get the fan seated on the key. It is working fine. No clearance issues. Putting out 14.7 volts. With the headlights and heater fan turned on, 13.7 volts.

I just wanted to touch base on the previous question I posted. Is the fan really supposed to go past the keyway, bottom out on the spacer, then using clamping pressure from the pulley, spin in unison? Or, is the fan and pulley linked together by the key?

Linking them together is the only way it is actually working properly...

I got a new alternator locally that seemed to have too short a shaft. This was corrected when I installed the pulley. The pulley securing nut pulled the shaft out a little farther and all was good. Sounds like you have the opposite problem, although you might try tightening the pulley down just to see if there is any improvement. Yes, the key must engage the pulley. If it doesn't, you may have a pulley designed for another application. Compare with others on Google images or Ebay.

Josh.

The fan is just thin sheet metal, it is not keyed to the shaft. The keyed pulley should seat all the way down the shaft so it pinches the fan against the spacer.

I spent years changing out customer pulleys and fans over to rebuilt units and remember well the fans spinning free when using an impact to loosen the nut.

Kelvin.

X2 with Kelvin.. Never been a problem as the pulley will hold the fan in place.

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Gary

Murphy's law

Tell a man there are 300 billion stars in the universe, and he'll believe you. Tell him a bench has wet paint on it, and he'll have to touch it to be sure.

Hi Kelvin & Gary,

I am certain that your comments prove my suspicions that something is wrong. I posted photos in the beginning of this thread. The old and new alternators side by side with the thrust spacers installed on each one. The physical dimensions of both shafts are identical. The only difference is the spacer sits 2.5mm further down the shaft into the housing on the new one.

The result is as follows... The spacer is slid onto the shaft. The fan is slid onto the shaft past the keyway and against the spacer. The pulley is slid onto the shaft and over the keyway engaged with the key. I add the lock washer and nut included with the new alternator. I am able to tighten the nut completely to the bottom of the threads cut into the shaft. At this point... The fan spins freely and is not pinched tight against the pulley and spacer. Several fan blades rub against the cast housing as I give it a little spin by hand.

A: Adding the G10 spacer that I made and mentioned previously fixed this.

B: Moss csr suggested that perhaps I have the wrong fan?

My fan came off my 1979 B and it has "Lucas" stamped on it...

Thank you all for your time and attention.



Edited 1 time(s). Last edit at 2017-01-19 06:38 AM by trapsailor.

Josh.

It sounds like you have it assembled correctly. The supplied spacer should allow the original Lucas fan to clear and the pulley to fully seat against it. This is not something I've run into before, so something is off. Once in a while we do get alternators that are missing the spacer, nut or a combination. In that case an incorrect spacer may have been supplied by mistake. Let me know if the alternator was in the original green package and if there was a plastic collar around the woodruff key and spacer area. Feel free to PM me with details and I'll try to get to the bottom of the problem.

Kelvin.