For me it's a daunting project (ST1100 alternator)

[kiltman]

The back story.... I noticed that my alternator just wasn't putting out the voltage, when cold I would get 14.2 volts at the battery but when the engine warmed up it would drop down to 13.9 and 13.7 with no load and when I used my heated gear or PIAA lights it would drop down to 13.3... still charging yes but there is a problem. Brushes, voltage regulator, rectifier came to mind and preping myself for changing those out and the cost I decided I would just bite the bullet and put a new one in. I too have gone with the aftermarket unit.
I had no intention of doing an upgrade on my 1990 so I opted to buy a post 96 ST and gave the '90 to a buddy of mine and he did the upgrade.
So... here I sit and now have to me a daunting project. I've gathered the tools and ordered some O-rings oil seals and rubber boot some of which are on back order here in Canada but hopefully they will arrive in January.
I built a lift for this project and I have to say I'm very pleased with it. I've screwed up my courage and have begun the task of taking off the swing arm. I started yesterday and this morning I have accomplished getting the swing arm out. Regardless it's a good thing I've gone and done this as I discovered that there is some surface rust on the shaft. The U-joint is OK it operates smoothly but the first impression was not good. I'm cleaning it up and everything seems to be servicable. My bike is a '97 with ABS and a California model, so lots of extra plumbing for brake lines as well as a disconnected Evaporation canister. (The PAIR system has been removed by a previous owner) I have a feeling the boot wasn't on properly and that's how moisture got in. The swing arm looks good and solid, I've done an initial clean but shall do a detailed inspection to make sure it hasn't been compromised. Over the weekend I will take out the alternator and install the new one.
It wasn't as bad as I thought, I'm one third of the way through the project and I'm getting confident that I can do this.

 

[DeanR]

Hope things go well for you Robert.
Those pictures look kinda nasty.
Swingarm off is a great start!

 

[Jim Van]

Looks like you are having fun !! How does the u-joint feel ? I have one that feels like new. $50 including USA shipping ( extra for shipping to CAN ). How many miles on your ST, Kiltman ?

 

[ReSTored]

Hope things go well for you Robert.
Those pictures look kinda nasty.
Swingarm off is a great start!

Yes, looks like the boot was leaking or maybe a PO used a pressure washer on the bike. Hopefully only cosmetic and no real damage.

 

[kiltman]

Looks like you are having fun !! How does the u-joint feel ? I have one that feels like new. $50 including USA shipping ( extra for shipping to CAN ). How many miles on your ST, Kiltman ?

Thanks Jim. The U-Joint feels good. no slop and feels smooth no notchyness. I can get the whole shaft with a good U-Joint from a parts bike for $40 Canadian here locally. Thanks though much appreciated.

I am having fun....there's also a sense of accomplishment. I reread the instructions and the alternator should be rather straight forward. Undo the three bolts turn clockwise till I clear the boss and install an 8mm bolt to hold the gears in place and pry loose and tetris it out.

This ST has 114K I bought it with 77K.
The timing belt and waterpump have been done, Head bearings done. Just the routine maintenance to do. Flush the fluids in the spring and I'm good to go for a few years.

 

[kiltman]

Yes, looks like the boot was leaking or maybe a PO used a pressure washer on the bike. Hopefully only cosmetic and no real damage.

I think you are correct about the pressure washer. I don't use one at all. Just a bucket and wash mitt seems to do the trick.

 

[gmtech94]

You can buy some rust remover at NAPA for a little money and wipe it on then off with a rag ,rust will be gone .Makes this an easy cleanup job for rust .

 

[kiltman]

update. The new alternator is installed! 15 minutes was all it took to swap out the old one and put in the new. Now to put the swing arm and other parts back together. but first some cleaning is in order.

 

[John OoSTerhuis]

Brushes, voltage regulator, rectifier came to mind and preping myself for changing those out and the cost I decided I would just bite the bullet and put a new one in.

The price of the fairly recently available aftermarket 40amp unit makes this a reasonable decision.

Nice job, Robert!

Regards, John

 

[DeanR]

None of that 'Lewis pin' business to deal with for the install?

 

[kiltman]

None of that 'Lewis pin' business to deal with for the install?

Not for the post 96, however there is a possibility you would have to use the Lewis pin if you neglect to do a procedure.
You need to acquire a 8mm bolt to make this work. You loosen the three bolts holding the alternator and remove them. Do not take the alternator out, instead rotate it clockwise so that the bolt holes are revealed. Use that 8mm bolt and screw that in on the left hole. This keeps the internal gear in place. Now you can remove the alternator. If you don’t put the bolt in the gear mechanism will come out and that’s when you will need to use a Lewis pin to line it up.

 

[Rob20111]

Good job.

 

[kiltman]

The price of the fairly recently available aftermarket 40amp unit makes this a reasonable decision.

Nice job, Robert!

Regards, John

I agree, John, and that was the reason I chose to go this route. I will have a closer look at the original unit at a later date, possibly service it so that I have a spare for the future.

 

[DeanR]

Not for the post 96, however there is a possibility you would have to use the Lewis pin if you neglect to do a procedure.
You need to acquire a 8mm bolt to make this work. You loosen the three bolts holding the alternator and remove them. Do not take the alternator out, instead rotate it clockwise so that the bolt holes are revealed. Use that 8mm bolt and screw that in on the left hole. This keeps the internal gear in place. Now you can remove the alternator. If you don’t put the bolt in the gear mechanism will come out and that’s when you will need to use a Lewis pin to line it up.

Would this hold true when replacing the 28 amper with this unit?

 

[kiltman]

Would this hold true when replacing the 28 amper with this unit?

No, as you have to modify the alternator shaft asembly so that the 40 amp alternator can mate up properly. The procedure is described in the Clymer manual pg. 303

 

[Jim Van]

update. The new alternator is installed! 15 minutes was all it took to swap out the old one and put in the new. Now to put the swing arm and other parts back together. but first some cleaning is in order.

Tah, Dah !!! Congrats on not being too intimidated to take this job on.

 

[kiltman]

Tah, Dah !!! Congrats on not being too intimidated to take this job on.

Thank you Jim. I'm feeling rather chuffed. I've received some good advice from you and other members here that has helped deal with my angst on contemplating doing this procedure. The other good thing is I'm getting most of the red dust from PEI out....it's amazing where I'm finding it...

 

[John OoSTerhuis]

Dean, when replacing a 40amp unit with another 40amp unit the Alternator Shaft Assembly remains in the engine case with its split gears still meshed with the flywheel splines.

Good tip about securing the Alt Shaft Assy before pulling the alternator, Robert! Did you have to remove and notch the cover on the back of the alt(s)?

John

 

[kiltman]

Dean, when replacing a 40amp unit with another 40amp unit the Alternator Shaft Assembly remains in the engine case with its split gears still meshed with the flywheel splines.

Good tip about securing the Alt Shaft Assy before pulling the alternator, Robert! Did you have to remove and notch the cover on the back of the alt(s)?

John

I did not have to notch out anything. From my understanding the post 96 have a frame modification. Honda dispensed with a frame support in the area of the alternator to make it easier to remove and install the unit. From 1990-1995 0ne has to notch or take off the cover.
The old alternator came out with a couple of twists ,and the new one, I had to make three attempts before I got it to go in. It was installed in no time.
I also alternately tightened the bolts, this brought the alternator to the motor without having to push hard to get the unit to seat.

I did have a duh moment. with regards to securing the alt shaft assembley. I thought I was suppose to use one of the alternator bolts and put that in the bolt hole...but the bolt sticks out a couple of inches and you can't get the alternator out.... I had to search my shop for an 8mm x 5/8" long bolt. Once found that worked perfectly. a palm to the forehead moment.

 

[Jim Van]

I didn't need to remove the alternator cover on my '98 either. And like the Kiltman, I had to play around with the alternator a bit before it slipped in.