Author Topic: I need help getting pulley off of a Mecc Alte  (Read 1366 times)

tyssniffen

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I need help getting pulley off of a Mecc Alte
« on: April 11, 2023, 04:23:04 AM »
So, with my chinese ST down (I believe it is the windings with a short) I have been gifted a 2013 Mecc Alte alternator off of another gen set.

It's gotta run at 3600rpm, so I need to put a different pulley on there.  Amazingly, I think it needs a 4" with my flywheel, which I have.

BUT, I can't get the other one off. It seems as though it's put on the opposite way the ST ones go on, with bolts on the *inside*.  I also don't know how to get the 'key' out off the shaft.

I've emailed the company (in Italy) a week ago, and haven't heard anything.  No luck doing internet searches either.  Anyone have ideas?

I have turned the bolts (out) which, once they are fully out and pushing against the cast body) may be pushing the pulley off, but I have worked that as hard as I can and have started to round off the bolt heads.    There must be a trick, but I don't know what it is.    I've also tried heating up the pulley a bit with a blow torch, but hard to say if I did enough, or if that was a wise move.

Photos attached.

6/1 with 2 tank for WVO.  pushing power into off-grid house battery bank, in winter.

tyssniffen

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Re: I need help getting pulley off of a Mecc Alte
« Reply #1 on: April 11, 2023, 04:23:43 AM »
more photos
6/1 with 2 tank for WVO.  pushing power into off-grid house battery bank, in winter.

dax021

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Re: I need help getting pulley off of a Mecc Alte
« Reply #2 on: April 11, 2023, 07:02:34 AM »
That centre part is a cone and the pulley has been put on backwards, so you need to soak well in WD40 then knock the outer pulley inwards, toward the casing.  This should allow the inner split cone to expand enough to slide off.

dax021

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Re: I need help getting pulley off of a Mecc Alte
« Reply #3 on: April 11, 2023, 07:04:32 AM »
By trying to push it off by backing out those bolts will only cause the inner cone to push further into the outer pulley, thereby tightening it on the shaft.

broncodriver99

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Re: I need help getting pulley off of a Mecc Alte
« Reply #4 on: April 11, 2023, 07:28:15 AM »
That's a taper lock bushing and sheave. Whomever assembled it put it on backwards, most likely for alignment reasons. There should be two threaded holes in the face of the bushing(the inner part)(facing the generator), they are "jacking" holes. Usually one would just use two of the bolts removed but since your bolts are captured you would need two bolts the same size but short enough to fit between the face of the generator and the bushing. Screw them in and they will force the pulley off of the bushing. You don't have much room so may have to get creative with sliding washers between the bushing and pulley to work it off. It is a taper fit and would be very difficult to drive the bushing in. Usually when I come across that I just cut the pulley parallel to the shaft so it will come off of the bushing and then pry it off of the bushing. Once the pulley is off it releases the taper lock and the bushing can then be removed.
« Last Edit: April 11, 2023, 04:13:49 PM by broncodriver99 »

hwew

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Re: I need help getting pulley off of a Mecc Alte
« Reply #5 on: April 11, 2023, 08:07:18 AM »
Purchase or rent a bearing puller. If the puller wedge is too thin. Use thin pieces of steel to close up the gap between the pulley and bushing flange.

The picture below shows the type of bearing that might work. The only concern would be if there is enough space between the generator head and the pulley to slide the puller in place.

There might possibly be a threaded hole in the bushing flange to remove an Allen screw that is holding the allen screw in place.

broncodriver99

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Re: I need help getting pulley off of a Mecc Alte
« Reply #6 on: April 11, 2023, 04:09:42 PM »
Having taken a closer look at your pictures this morning there is no way you are going to be able to use the jacking bolts to push the pulley off of the taper lock bushing, not enough room. One thing you dont want to do is push against the generator body. Taper locks will not budge. I think it is time for the cut off wheel and split the pulley.

One other posibility is to try using a wide chisel as a wedge between the pulley and the bushing to try to separate them. Working back and forth side to side. If you can get the pulley to budge a little it may go ahead and come off.
« Last Edit: April 11, 2023, 04:17:35 PM by broncodriver99 »

hwew

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Re: I need help getting pulley off of a Mecc Alte
« Reply #7 on: April 11, 2023, 05:22:28 PM »
Broncodriver99,
Thatís what I figured.
My 1st thought was to try something like that this. Pretty much the same as your idea.

 Picture posted below:

It might have to be cut thinner near the thick end to work.
Word of caution make sure the other end of the pulley and bushing that is 180 degrees from the driving end is up against a heavy solid piece of steel that is resting against a wall. This way there is less of a chance of damaging the shaft and or bearing. I jus donít like beating on things.
The best way is bring the whole unit to a machine shop and have them drill 2 holes 180 degrees apart, parallel with the shaft through the pulley. Drill the holes to accept a 1/4Ē or 5/16Ē or similar tap. Make Shure the hole are directly in the center of the inner flange face on the bushing. Use high grade bolts. It should push the pulley off the bushing.

I canít believe that the manufacturer didnít drill 4 through holes and tap 2 of them in the pulley so the pulley can be assembled and removed easily. Of course there is a possibility that the pulley is too small in dia. And the holes would be exposed in the pulley grooves.
« Last Edit: April 11, 2023, 06:14:44 PM by hwew »

tyssniffen

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Re: I need help getting pulley off of a Mecc Alte
« Reply #8 on: April 11, 2023, 05:38:11 PM »
thanks for all these replies.

seems like I definitely need to try and get the pulley to move IN first, something I didn't try much, as I didn't really believe it could be on backwards.
6/1 with 2 tank for WVO.  pushing power into off-grid house battery bank, in winter.

hwew

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Re: I need help getting pulley off of a Mecc Alte
« Reply #9 on: April 11, 2023, 05:53:45 PM »
If the pulley was machined properly in the beginning, you wouldnít have this problem. Iíve seen many pulley/bushing combinations installed this way. The fastening bolts would normally go through the pulley first. Then the busing should have threaded holes also on the flange. It could of been assembled either way.
« Last Edit: April 11, 2023, 05:56:21 PM by hwew »

broncodriver99

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Re: I need help getting pulley off of a Mecc Alte
« Reply #10 on: April 11, 2023, 10:13:03 PM »
teems like I definitely need to try and get the pulley to move IN first, something I didn't try much, as I didn't really believe it could be on backwards.

No, you want the pulley to move out, as in separate from the bushing. They are tapered inside so the closer the pulley is to the flange of the bushing the tighter it is locked to the shaft. The bushing is not going to move on the shaft until you get the pulley off which means it needs to move away from the bushing flange and generator. You may be able to get a large enough puller in there but looks pletty tight.

Here is a link to a diagram and instructions pdf.

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.martinsprocket.com/docs/catalogs/power%2520transmission/3_bushing%2520catalog/qd-bushings-catalog.pdf&ved=2ahUKEwix-_Dy3qL-AhVbEFkFHSDaAwgQFnoECBIQAQ&usg=AOvVaw3T-3NYNMyBNBV6oco_5WdS
« Last Edit: April 11, 2023, 10:15:16 PM by broncodriver99 »

hwew

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Re: I need help getting pulley off of a Mecc Alte
« Reply #11 on: April 11, 2023, 10:45:58 PM »
1+++

tyssniffen

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Re: I need help getting pulley off of a Mecc Alte
« Reply #12 on: April 12, 2023, 04:04:46 AM »
update - not done yet -

I've gotten some movement, but the 2 parts on the shaft, not between pulley and the bushing.

I cut the bolts, both cut the heads off and cut the shaft between the pulley and the bushing, as I was concerned they were holding the 2 together.  And a hack saw was easy to get in there.

I've got some stubby bolts and nuts and using them as expanders, pushing up/away on the pulley, but not getting it free yet.  I have also been hitting down/in on the bushing while the expander nuts are holding the pulley up, hoping they'd move apart. it occurs to me as I type this I was hitting down on the whole thing, so that I wasn't putting real movement on it - by having the shaft on the bench, I was just pounding down. I should have it hanging by the pulley somehow.

Still open for more advice. thanks for the PDF.
6/1 with 2 tank for WVO.  pushing power into off-grid house battery bank, in winter.

hwew

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Re: I need help getting pulley off of a Mecc Alte
« Reply #13 on: April 13, 2023, 10:56:07 AM »
Been thinking of Mcc Alte generators. Some of the 2 bearing portable heads use the same rotor and stator assembly as the single bearing, direct drive heads. A stub shaft would be installed in the tapered end and secured the a long bolt that runs through the entire length of the generator shaft.

Remove the rear cover and look at the rear bearing. If it has a bolt in the center of shaft then the aft end is removable.

If there is no bolt in the center of the shaft, then the generator head has a full length shaft.

tyssniffen

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Re: I need help getting pulley off of a Mecc Alte
« Reply #14 on: April 19, 2023, 06:31:31 PM »
UPDATE:

I got it off, see attachment.    In the process of trying to get a wedge between pulley and bushing, the bushing started cracking, so I started smashing it apart. 

Now I need to find a new bushing that will fit a 1 inch diameter shaft and a 2 1/8 inch pulley hole.   anyone have any shop recommendations for that?
6/1 with 2 tank for WVO.  pushing power into off-grid house battery bank, in winter.