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Discussion Starter #1
Put a new stator in, what a pain, and now the engine won't turn over. Any idea what I have done?
 

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Discussion Starter #2 (Edited)
Battery is fully charged, bled the clutch a few times but it is difficult to find neutral so it needs that done again. When I put it in gear I cannot use the rear wheel to move the pistons where I could before I did the stator replacement. The case cover seemed to go on easily enough with no binding, and the new stator appeared to be a close fit just like the old one. The old one showed no real signs of wear and the wires seemed ok too.

When I press the starter button, I hear the starter motor struggle to turn, so I switch it off quick. I have done this four times and did not like the sound at all.

I changed the stator because I was measuring only 20-25 v AC from idle to 6,000 rpm.

That clutch rod that goes thru the engine block, I took it out to remove the old case cover, was that bad?
 

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Discussion Starter #4
That is the plan in about 12 hours, was hoping someone had an insight into what I have messed up. I mentioned the clutch rod, but since I can definitely get the bike in neutral, that must not have anything to do with it. I scares me to think the new stator is rubbing on the alternator magnets, I did test fit it and it seemed to have a reasonable gap, before pressing it into the case cover. And like I said, the cover went on smoothly.

Is there anything I could have done to the starter while in there?
 

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Don't do anything drastic right now, give your post some time for the experts to read it and chime in.
 

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As chuckracer said you need to back track to fiind the problem.

I see nothing related to the pushrod, something you have done has caused an interference and you risk damaging parts if you keep forcing the issue.

If you cannot turn the motor over by hand with no spark plugs in the engine hard parts are hitting and something might break, take your time and look things over carefully. Something you just touched is wrong. It may be a defective new part or assembly error but if it was working before and now it isn't you need to investigate where you were.


NOTE!!!
There are times when you get bit by the bad luck bug, I had a Husqvarna ride into the shop for a water pump seal. The seal was changed and then the bike would not start, we assumed we disturbed some wire somewhere as we had no spark. Turned out his flywheel had chosen to become unbonded at just that moment so it had nothing to do with us, strange things do happen.
 

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You say you test fitted it to check the clearance, and it was OK. But then you must mount stator in side cover -- any chance that this could be mounted skewed? That would make it rub the stator if it were crooked.
 

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On my ST2 it can't go on that crooked. Ive had that side case off 3x and the magnetic force always guides in in perfectly.
I know its a different bike, but still- GL
 

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Discussion Starter #11
Something is not lining up, that is clear. But I don't see anyway the stator is not lined up, I had to pound it in with a rubber mallet. The two screws at the end make sure it is level, I think,...
 

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Any chance you put the stator in upside down? Don't ask how I thought of this.
 

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Discussion Starter #13
Any chance you put the stator in upside down? Don't ask how I thought of this.
I put it the way it came out, wire side into the case cover. Got the slots to line up with the two bolts that compress it. Maybe I need to tweak them down another turn?
 

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Discussion Starter #14
Got the case off, immediately noticed the stator was not seated deep enough for one of the coils - it galled the surface. Looking closer it looks like another coil also rubbed but not enough to make a serious mark. Cleaned off the galled metal, smoothed it down, and went like a mad man pounding down the stator with a rubber mallet. Don't think I even budged it. Cranked the two bolts down until I thought the threads would give and it didn't move it either. There is a millimeter lip around the stator. Put it back in, still won't turn.

I am thinking that the old gasket goo that was on there was thick as hell, is that the key to making this work? Was there a real gasket there originally? I think really thick goo would lift it out enough to keep it from scraping, but I do think the original was set in deeper.
 

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Discussion Starter #16
1991, pre production model built May 1990.

Looks like the wire coils are hitting.

Jiggered around with five bolts and the case remover tool and found the gap I needed not to hit. About 2mm, I think the goo can handle that. Slathered it up like my PBJ sandwich, carefully centered it with the gap even all round measured by my fingernail. Gently snugged the bolts pressing against the case remover tool then laid a bit more smoothing goo around it and cleaned up. I am going to let it set overnight and tightened the bolts just another 1/2 turn tomorrow against the cured goo. I don't think it will leak, and if the bolts have enough goo on them they won't twist out either.

Wish me luck.

If this works - One, the stator did not fit my model. or Two - poor quality control on the windings. or Three - they originally designed mine with a real gasket and not goo. I noted that whoever did this before was really heavy on the goo also, which I thought was just a sloppy job, but maybe not?
 

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Is this a new replacement stator or a rebuild? The new one I got for my 98 ST2 was incorrect. Rick's rebuilt my old one and it works AWESOME.
 

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Discussion Starter #18
I think the one I took out was rebuilt, hard to tell, but it looked like a refurb unit. The new one I put in looked new.
 

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your era of 900 has a short crankshaft and a different cover than the later models pre-98. I have one in the shop apart and can check to see if it is different from the later stators.

That era did use a paper gasket but we always removed them and used sealers because the paper gaskets leaked often.If you have a clearance issue it is not correct, you should be able to assemble with sealer and no rubbing parts.

Who made your new stator? Is it the same size as the one you removed? I assume that one did not rub.
 

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Discussion Starter #20 (Edited)
Motorcycle Parts: Repair & Maintenance - BMW, Moto Guzzi, Ducati sold me the stator, and within the 1-2mm tolerance it seems to be critical over they look the same to me.

Paper gasket, eh? That is half of the distance needed here for this job. Still suspect the new stator had the windings too high for clearance. I could see two places where it hit, one badly that I pictured above in the thread. Doesn't look like the copper winding severed, but it is now exposed - the coating is worn off. Will this be a problem?

Low profile bolts? Hmm, I used the ones I took out, but they don't look much different that the ones holding the case on, maybe a bit thinner on the head. Hell, if this doesn't work I will go back in and check that.

I am going to let the goo cure overnight, and give it another twist on the bolts in the morning. Right now with the goo filled gap of about 2mm, the wheel turns with no rubbing inside the case cover that I can hear with a stethoscope.
 
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