Tips on removing the stator

[AnnapolisAirhead]

I am replacing my alternator brush holding plate assembly with a new one and it appears that I need to remove the stator housing to access the rear bolts of the brush holding plate.

Other than disconnecting the battery (which is sitting on the bench now), does anyone have any sage advice for doing this? Looking at it and reading the Clymer's, it looks sort of straight forward. So far, the only two things I've been told to do are disconnect the battery and be careful to note the order of washers (fiber, etc.).

Just thought I'd ask for advice from others who have actually done this before. It's a 1983 R100T (electronic ignition).

Thanks in advance.

[cjack]

I am replacing my alternator brush assembly with a new one and it appears that I need to remove the stator to access the rear bolts. Other than disconnecting the battery (which is sitting on the bench now), does anyone have any sage advice for doing this? Looking at it and reading the Clymer's, it looks sort of straight forward. So far, the only two things I've been told to do are disconnect the battery and be careful to note the order of washers (fiber, etc.).

Just thought I'd ask for advice from others who have actually done this before. It's a 1983 R100T (electronic ignition).

Thanks in advance.


When you remove the bolts holding the stator in place, be cautious to remove the
frame of the stator and the lamination section as one. It is possible to pull the frame loose and have the lamination section with the windings remain which stresses the wire connection between them. Other than that, when you reinstall the stator, be sure that it is seated all around against the mounts before tightening the bolts (not cocked to one side).

[AnnapolisAirhead]

When you remove the bolts holding the stator in place, be cautious to remove the
frame of the stator and the lamination section as one. It is possible to pull the frame loose and have the lamination section with the windings remain which stresses the wire connection between them. Other than that, when you reinstall the stator, be sure that it is seated all around against the mounts before tightening the bolts (not cocked to one side).

I guess I need to remove the housing (p/n: 12311243002). Is that part laminated or are you saying I need to remove the housing with the stator? After looking at the microfiche on maxbmw, looks like I'll have to separate the housing from the stator to get to the nuts on the back of the housing that hold the brush holder plate (p/n: 12311243003) in place.

Maybe I am making this confusing. It is the brush holding plate that I am trying to replace. So, I need to slide the stator housing off to get to the nuts holding the brush holding plate on to the stator housing. So what is laminated that I need to be careful with? :dunno Can't the stator stay in place?


Thanks.

[cjack]

I guess I need to remove the housing (p/n: 12311243002). Is that part laminated or are you saying I need to remove the housing with the stator? After looking at the microfiche on maxbmw, looks like I'll have to separate the housing from the stator to get to the nuts on the back of the housing that hold the brush holder plate (p/n: 12311243003) in place.

Maybe I am making this confusing. It is the brush holding plate that I am trying to replace. So, I need to slide the stator housing off to get to the nuts holding the brush holding plate on to the stator housing. So what is laminated that I need to be careful with? :dunno Can't the stator stay in place?


Thanks.

I just meant that if you pull on the housing, the windings on the laminated core can be stuck a bit to the engine front mount and you risk pulling on the wires connecting them (the housing and the laminated core with the wire windings). Later, you will have to separate them, I think somewhat, to get to the back of the housing, I don't remember if you can pull them apart enough without unsoldering the wire winding lamination section from the housing connections...probably.

[20774]

It's pretty straightforward. Just be careful not to pry on the windings or damage them. Use a piece of wood and work on the housing, not the windings.

I tried to replace my brushes once, but gave up. I wanted to remove the housings that the brushes were in but could not, for the life of me, get the inside housing off. I requires some kind of special wrench, bent or something. I tried heating a open-end wrench up and bending it, but I could never get enough bite on the nut. I was afraid of doing more damage. So, I caved and put it all back together.

[AnnapolisAirhead]

I just meant that if you pull on the housing, the windings on the laminated core can be stuck a bit to the engine front mount and you risk pulling on the wires connecting them (the housing and the laminated core with the wire windings). Later, you will have to separate them, I think somewhat, to get to the back of the housing, I don't remember if you can pull them apart enough without unsoldering the wire winding lamination section from the housing connections...probably.

Ah, I figured it out. I did not know that they were attached (wired) because every manual I searched online or Clymer's showed them as separate parts. Since all I wanted to do was get to the brush holding plate nuts on the back, I thought the stator could stay put. Wrong.

Anyway, I thought the stator must surely be frozen to the aluminum of the timing chain cover but it was just the magnetic hold, so I eased it off about a 1/16 o 1/32 of an inch as a time so as not to damage the stator or rotor. Its worse getting it back on the bike.

It's pretty straightforward. Just be careful not to pry on the windings or damage them. Use a piece of wood and work on the housing, not the windings.
Good advice and an expensive mistake if you don't.


I tried to replace my brushes once, but gave up. I wanted to remove the housings that the brushes were in but could not, for the life of me, get the inside housing off. I requires some kind of special wrench, bent or something. I tried heating a open-end wrench up and bending it, but I could never get enough bite on the nut. I was afraid of doing more damage. So, I caved and put it all back together.

When I got the stator and housing on to the bench, I thought I was home free. How hard could a pair of 8mm nuts be to remove? I hit the same problem you did Kurt. Anyway, I was able to heat a Craftsman 5/16" ignition wrench in the middle and bend it at to about 75 degrees. I first heated the 8mm but broke it because I was trying to bend it too close to the box end (d'oh!).

btw, when I had both inside nuts loose, I kept the stator housing bench side down (so I had a rotor's view of the stator so-to-speak). Trust me, do it this way. There are wave washers, fiber washers, spacers, lock washers, etc. and they are not the same on both posts. A tech at Bob's BMW told me to pay very careful attention to what goes where. Leaving the stator housing bench side down was sheer dumb luck, as I got the interior nuts off, I carefully just lifted the stator and housing off the old brush holding plate with all washers (on the inside) in the exact same place then lowered the assembly down onto the new brush holding plate.

It's worth noting that the new holding plate ships with the brushes already soldered, insulated, new springs, etc. and the springs are NOT pushing the brushes down into the housing completely. It's best to leave it this way so that when you go to put the assembly back onto the bike, the new brushes aren't in the way, dragging on the rotor.

It took some very careful, gentle persuasion to get it back on evenly (thanks for the tip CJack), but I got it on evenly all around, then slowly fastened the 3 allen bolts, evenly.

I gently pushed the brushes down until I heard the springs snap into place and verified they were pushing on the brushes. Lastly, I reconnected all the wires (I had sanded all the connections, sprayed with contact cleaner and use die electric grease on them. Did the voltage regulator too.

All this and now I am thinking maybe I'll do the Motorrad Elekt 400w kit because the rotor and the stator were scored more than a little. I sprayed contact cleaner on them, but we'll see how this goes.

Thanks for the help. I took lots of before and after pics but am a bit tired, greasy and rambling. If anyone wants to see them, PM me. If I had to do it all over again, I would. Even though the brushes are cheaper ($7/pair), you have to go through the same trouble AFAIK and you need to retain the wire insulation from the existing brushes, re-use it then solder the end points of the brushes onto the old holding plate--which should be cleaned shiny bright. The brush wires are braided copper and act as a wick when soldering, so you'd need to be careful to avoid that as it'll make them brittle and restrict he springs ability to push the brush down as it wears. So for an extra $43 bucks (Bob dollars, so probably cheaper at Chicago BMW or eubmw.com in Great Falls, VA), I avoided any soldering. Just my 2 cents.

Time for Guiness. :drink