V1000 G5 Stator Removal (again))

[ozarquebus]

 Well, I thought I was ready and I read every post I could find on stator removal and decided to just make the pin that is inserted into the center shaft, then reinsert the allen head stator bolt to put pressure on the taper and rap it. It comes right off, right?
Well mine won't come off and I can't get the home made extractor pin out.
 I think the steel of the pin may be too soft and it may be bent in there, but I hope not.
 What next, now that I have screwed it up?

[Groover]

If you can get the stator out eventually, the homemade pin should be accessible to come out. Not sure, my thoughts are very hack-ey at the moment to the point I don't even want to suggest anything, but.... Is the rotor toast and you are replacing it? If so, maybe you can gently tap in round and round and maybe it will break loose?

I broke the rotor bolt in mine one time, and the stress level hit the roof. It actually ended up coming out very easily in my case. Then I bought the removal tool 

Hopefully someone has a better suggestion

[pehayes]

Lucky you.
I did something similar many years ago.
I made a custom puller for my slap hammer.
I'll send it to you.
You will need to pull the front wheel and fender so you have direct access.
I'll send a picture later.  Hate working from a phone.

Patrick Hayes
Fremont CA

[Rolf Halvorsen]

I am a bit confused. Stator = stands still. Is the outside parts which is hold in position by 3 M5 screws. Easy to remove.

Rotor is the rotating inner part, which is removed by extracting it out using a HARDENED STEEL pin + the original bolt. Screw the bolt fully in and apply a hammer blow on the head(of the screw).

If you have used SOFT STEEL, then sorry for you. You might have big trouble to remove the soft steel part.

The gold long hardened special M8 screw fully left in the picture), is made by me for this work.

[wirespokes]

Ouch!

I think everyone has tried that approach, very few succeeded. If all mention of it could be erased from history, I'd do it.

The pin is now jammed in the end of the threaded crankshaft. Hope the threads are ok.

The rotor is held on mostly by the taper - it's a taper fit and requires a good blow usually to break loose, but a puller will do it too. That's what the proper tool is all about. But a regular gear puller at this point won't work since there's no way to push on the crankshaft end. The only solution now is the slide puller.

[travelingbyguzzi]

For a removal pin, I cut down a 5mm Allen wrench. Plenty hard and most of us have more than we need.

[pehayes]

OK, here's the tool.  An original rotor bolt welded to a threaded shaft that fits my slap hammer.  Screw this into the rotor.  Get the wheel and fender out of the way.  Use the slap hammer to yank the rotor off the nose of the crankshaft.  The residual piece inside the hollow crank will likely come out easily unless you have really done some bad damage.



Now you know why the factory pin tool is made from a hardened shaft.

Give me a PM with your postal address so I can send it along.  Find a slap hammer that fits the pulling thread.

Patrick Hayes
Fremont CA

[ozarquebus]

Yes its the rotor not the stator. The stator came off easy. The alternator is in good shape in general. Just taking it off to get at chain and damper. Everything from the fender to the exhausts and even the front engine mounting bolt all came apart easy.

[wirespokes]

Have a big box with lots of padding ready to catch the rotor when it pops off. Even with the proper tool the rotor can fly and crash to the floor, so create a soft place to land. The rotor is rather heavy and a bit much to control at the end of the slide hammer, so don't expect to be able to keep it from crashing. It will.

[pehayes]

I sent this as a PM to the OP but then I thought there might be some others who are new to Guzzi and need to know how this alternator system is attached.

You made an extractor 'removal pin' of soft metal.  What dimensions did you use for that tool?  The length is critical.  Here are the dimensions of my factory tool:

5.97mm or 0.235" diameter by 52.57 mm or 2.0695" length

Are  you certain you know how the factory pin tool works?
Look at my photo above again.  See the length or number of turns of thread on the business end?  Important number of threads.  I think about 10-12 turns.

For a NORMAL INSTALL of the rotor:
Look inside the rotor body itself and you will see it has about 8 turns of internal thread.
Look inside the nose of the crankshaft and you will see about 8 turns of internal thread.
Put the rotor onto the tapered crank.
Realize that you now have TWO sections of internal threading but they are not continuous.  There is a significant blank, unthreaded internal space between the rotor's internal thread and the crank's internal thread.  That blank space is longer than the threaded portion of the central bolt.
Insert the central bolt and it impacts the internal threads of the rotor.
Spin the bolt in until ALL of the bolt's threads pass through the rotor and they now reach into the above described empty space.
The bolt is now free to spin and free to move slightly fore and aft.
Push the bolt in further until it impacts the internal threads of the crank.
Turn until the head of the bolt sets in the recess at the front of the rotor and tighten appropriately.

For REMOVAL of the rotor:
Note the internal threading descriptions as above.
Insert a properly dimensioned factory extractor 'pin' tool or a suitably HARD substitute.
The extractor pin tool must be long enough that its outer tip is outboard of the crankshaft internal threads and thus prevents the central bolt from ever reaching into the crankshaft internal threads.
Insert the central bolt and turn it in until it abuts the end of the extractor pin tool.
Tighten substantially to set up an internal pushing force to force the rotor to 'pop' off the crankshaft.  It is held only by taper friction, but that can be quite substantial.
Most have found that the rotor will not pop and thus a judicious hammer whack on the rotor body or central bolt may be the extra vibration needed to release the rotor.
The rotor will fall, so be prepared with a soft place to fall.

If your extractor pin was not sufficient length, that might allow the central bolt threads to reach in and grab the first few internal threads of the crankshaft.  Doing so would create a crushing force against the extractor pin tool but never apply any outward force to release the rotor.  Bad juju!

If your extractor pin was not HARD enough, it might bend or 'mushroom' inside the crank before providing enough force to pop the rotor off of the crank taper.

Someone makes and sells an extractor tool with bolt threads and the proper length extractor pin all in one piece.  I don't recall who.

Rotor, bolt, and factory tool in one pic:



Patrick Hayes
Fremont CA

[Antietam Classic Cycle]

Someone makes and sells an extractor tool with bolt threads and the proper length extractor pin all in one piece.  I don't recall who.

Here's one source:
https://www.euromotoelectrics.com/product-p/boalt-rotor642tool.htm

[wirespokes]

Or you can make an extractor yourself. I got a bunch of grade 12 (forgot the exact grade) allen bolts from Fastenall and turned off the end threads. It was one of my first projects after getting a lathe. Without a lathe, careful use of a grinder could accomplish the same.

[RinkRat II]

     Thanks Patrick, for the spec's on that pin!

        Paul B

[ozarquebus]

Thanks for the info, everyone. I will supply update.

[Chuck in Indiana]

Thanks for the info, everyone. I will supply update.

You are the first guy to do this..   

[Cdn850T5NT]

For REMOVAL of the rotor:
Note the internal threading descriptions as above.
Insert a properly dimensioned factory extractor 'pin' tool or a suitably HARD substitute.
The extractor pin tool must be long enough that its outer tip is outboard of the crankshaft internal threads and thus prevents the central bolt from ever reaching into the crankshaft internal threads.
Insert the central bolt and turn it in until it abuts the end of the extractor pin tool.
Tighten substantially to set up an internal pushing force to force the rotor to 'pop' off the crankshaft.  It is held only by taper friction, but that can be quite substantial.
Most have found that the rotor will not pop and thus a judicious hammer whack on the rotor body or central bolt may be the extra vibration needed to release the rotor.
The rotor will fall, so be prepared with a soft place to fall.

If your extractor pin was not sufficient length, that might allow the central bolt threads to reach in and grab the first few internal threads of the crankshaft.  Doing so would create a crushing force against the extractor pin tool but never apply any outward force to release the rotor.  Bad juju!

If your extractor pin was not HARD enough, it might bend or 'mushroom' inside the crank before providing enough force to pop the rotor off of the crank taper.

Patrick Hayes
Fremont CA

Have folks ever used some effective penetrating oil to help liberate the rotor from the taper?  I would, however, worry about the chemical action on the insulation and shellac(?) coating on the windings...

[Chuck in Indiana]

Have folks ever used some effective penetrating oil to help liberate the rotor from the taper?  I would, however, worry about the chemical action on the insulation and shellac(?) coating on the windings...

That wouldn't work. People just don't realize how strongly a precision taper holds. You could take the bolt out once the rotor is seated. 
It's the same way a drill chuck is held into the tapered shaft that is held by the taper of a drill press or lathe. It takes a sharp impact to break the taper loose.

[wirespokes]

What Chuck says. I'll also add that when replacing the rotor, clean the surfaces very well - tapers need to be mated up with clean surfaces.

[Moparnut72]

i work on outboard motors quite a lot, mostly old ones. On most of them the flywheel has to be removed to get to the ignition system. The flywheel is held on to the crankshaft by the same method namely a taper. They can mostly be removed with some sort of a gear puller. Once it is good and tight the flywheel can usually be loosened with a rap on the screw of the puller.with a hammer. However some can be quite stubborn and the possibility of mushrooming the end of the crank with several smacks from the hammer is a good possibility. I have found as well as many other outboarders that the use of a impact gun on the puller screw will usually break the flywheel loose with a minimal amount of drama. It is of course important not to turn the power of the gun to its max. Just enough to put pressure on the screw. It is mainly the impacts of the gun that "rattle or shock" is what breaks the fit of the taper. I think it would work here too. Just go gently.
kk

[Groover]

The older Vespa flywheel/rotor also mounts the same way, but also have a woodruff key. The woodruff key is to line up the flywheel up to keep the points lobe where it needs to be. At the time, we'd use small tire irons or big screwdrivers as levers, then hit the crank and the rotor would pop out. If the flywheels had broken fins, depending on the generation (some were heavy, some light) and say a few cooling fins were broken, then those flywheels would occasionally pop loose because of them being out of balance. Maybe the nut wasn't quite tight to specs, but either way, then it was all downhill from there in many cases. The loose flywheel then would shred the woodruff key which would scratch the tapered surfaces of the crank and flywheel, then it was harder and harder for them to stay on because of the damage. Of course, these problems were mostly on our souped up engines. Careful emery cloth work, then we'd get the tapers clean enough to get them stable again, not always. Sometimes we'd have to change the crank as it was softer than the flywheel cam part.

[Cdn850T5NT]

The older Vespa flywheel/rotor also mounts the same way, but also have a woodruff key. The woodruff key is to line up the flywheel up to keep the points lobe where it needs to be. At the time, we'd use small tire irons or big screwdrivers as levers, then hit the crank and the rotor would pop out. If the flywheels had broken fins, depending on the generation (some were heavy, some light) and say a few cooling fins were broken, then those flywheels would occasionally pop loose because of them being out of balance. Maybe the nut wasn't quite tight to specs, but either way, then it was all downhill from there in many cases. The loose flywheel then would shred the woodruff key which would scratch the tapered surfaces of the crank and flywheel, then it was harder and harder for them to stay on because of the damage. Of course, these problems were mostly on our souped up engines. Careful emery cloth work, then we'd get the tapers clean enough to get them stable again, not always. Sometimes we'd have to change the crank as it was softer than the flywheel cam part.

Groover - that's cool! Your're a two stroke guy! I would love to have a classic Vespa... P150, P200? I think they are. Can't seem to rid myself of this love affair, 2 stroke spooge-smell and all! I like the 4 speed manual Vespa's...

[Cdn850T5NT]

i work on outboard motors quite a lot, mostly old ones. On most of them the flywheel has to be removed to get to the ignition system. The flywheel is held on to the crankshaft by the same method namely a taper. They can mostly be removed with some sort of a gear puller. Once it is good and tight the flywheel can usually be loosened with a rap on the screw of the puller.with a hammer. However some can be quite stubborn and the possibility of mushrooming the end of the crank with several smacks from the hammer is a good possibility. I have found as well as many other outboarders that the use of a impact gun on the puller screw will usually break the flywheel loose with a minimal amount of drama. It is of course important not to turn the power of the gun to its max. Just enough to put pressure on the screw. It is mainly the impacts of the gun that "rattle or shock" is what breaks the fit of the taper. I think it would work here too. Just go gently.
kk

That IS a good idea... percuss the rotor off. As indicated, the torque setting would have to be low - that makes sense.

[Groover]

Yes, currently still have a P125x (177cc now), and a P200e both 4 speed. Growing up I went though at least half dozen 50 Specials, which at the time could be take up 130cc max, but now they have a gazillion kits types, some 180cc, and some extreme kits at 250cc. Best two stroke smelling oil I think, Motul 710 2T 

[theoneandonlymin]

Quite a while ago I bent a soft extractor piece inside my rotor. A tip was to screw in a grease nipple  and pump the rotor off. It worked so it did.

Cheers
Min

[Cdn850T5NT]

Novel idea. Do you have a picture of the fitting? Seems to me that the threading of the rotor would tend to leak grease... but if pump-in rate is higher it will deliver net pressure. Still, no "shock" to break-loose the purchase the rotor has on the nose of the crank.  Further to this... when people use the factory-provided pin - do they use the hammer to tap right on the head of the original screw, or use a piece of hardwood as a buffer, or tap laterally on the rotor?  Seems to me that only a slide hammer that grabs under the screw head (yet still leaves adequate threading into the rotor) would actually rap the rotor in the correct direction...  ????

[pehayes]

Seems to me that only a slide hammer that grabs under the screw head (yet still leaves adequate threading into the rotor) would actually rap the rotor in the correct direction...  ????

I don't think direction is important.  You already have outward removal force set up.  The hammer rap is merely to set up a vibration effect which helps to release the taper grip.

Patrick Hayes
Fremont CA

[Tom H]

The shock of hitting the bolt head with a hammer breaks it loose.

In my manual for my BMW, it calls for the service tool or a suitable substitute (I think it gave the dimension of the tool/rod) and to use the pinch bolt from the rear axle. Tighten it up holding the rotor by hand and rap the head of the bolt with a hammer.

I have done this on the BMW, yes it does just pop right off.

Tom

[theoneandonlymin]

Here you are from my special tools tin.......
8mm x 1.25 grease nipple.
Wind it in , pump it up, off it comes.
Hopefully.





Cheers
Min

[Chuck in Indiana]

^^^^ Nice.. I've removed blind bearings by making a punch that's a slip fit in the bore, putting grease in it, and smacking it with a copper hammer.

[Groover]

hydraulics.. who would've thunk - great tip!