Alternator core failure

Every thing back together and buttoning things up. New alt. charges at 14.4 Volts on the volt meter. The old one was at 14.1 which is plenty. Just the difference between the new and the old. So far the bike started and runs great. No leaks that I could see.
That was a big job that I am glad is over.
 
The output amperage naturally varies according to battery state of charge, load, ambient and component temperatures so without factoring test condition differences .3 volts may be misleading. Honda simply states output should be greater than standing battery voltage and less than 15.5 volts at 5,000 rpm. The new one passes as did the old one.
 
Well after all the work I did over the winter with the bike and having about 600 miles on odometer after the major overhaul. Some how I now have a coolant leak from the square hole coming out from the side of the crank case cover.. I doubly checked all hose clamps as I know these are prone to leaking and made sure all were tight. Can't imagine where the fluid is coming from --- Holy cow I don't want to go back into that V again. Super disappointing.:mad:
I want to try to look with a inspection camera but don't have one and I have read where you can't really see anything due to all the clutter in the V anyway.
I replaced all "O" rings and coolant hoses with new ones so I have no idea what is going on.
 
My alternator died on my '05 one month into my extended warranty. So I let the dealer swap it out.

Since then I have been collecting parts off ebay when I see them at give-away prices. I currently have 3 alternators in my parts bin. The only thing is I need to have them tested to make sure they work before I go using one.

And yes, I'll be doing my own work. I've removed plenty of throttlebodies and the alternator is right below that. I will admit the only alternator I have removed was in an engine already out of a bike.:rolleyes:
Well I’m in the market for an alternator, do you have a spare one still that you’d be willing to part with?
 
Also, to change out the water oil cooler water lines, it's best to drop the oil cooler down so you can get to the hoses.

Note: I have yet to find a replacement o-ring for the oil cooler (outer ring - Never have seen one in the diagrams? :think1:) Anyone else find one?)
Well Bob, they say that good things come to those who wait and that patience is a virtue. It was only 4 1/2 years coming, but it would seem that someone has finally found an O-ring dimension for this oil cooler. It apparently is a 58 mm ID x 64 mm OD x 3 mm cross section.
See this post-
O-ring actual fits the groove like it was made for it.
 
I had charging issues and bought a new rectifyer, replaced that with no change. So i gave up and I bought a "tested" alt that "tested" good off ebay. It was 450+shipping bucks and the repair was roughly 350 to have it put on. It worked for about a week. Then went out again. Since it took about 3 weeks to get in to the shop initially I was out side the mandatory 30 day warranty and the seller did nothing but blame the bike. Now I'm looking for a new altenator from a decent supplier but that seems to be pretty difficult. Any suggestions to find one under a grand??

I actually have one alt (with a brand new rectifyer) that is off the bike. I'm considering attempting to repair if parts are easier to find.
 
I had charging issues and bought a new rectifyer, replaced that with no change. So i gave up and I bought a "tested" alt that "tested" good off ebay. It was 450+shipping bucks and the repair was roughly 350 to have it put on. It worked for about a week. Then went out again. Since it took about 3 weeks to get in to the shop initially I was out side the mandatory 30 day warranty and the seller did nothing but blame the bike. Now I'm looking for a new altenator from a decent supplier but that seems to be pretty difficult. Any suggestions to find one under a grand??

I actually have one alt (with a brand new rectifyer) that is off the bike. I'm considering attempting to repair if parts are easier to find.
Partzilla is $800, Cycle Parts Nation is $752. Both OEM Honda part 31100-MCS-013.
 
I had charging issues and bought a new rectifyer, replaced that with no change. So i gave up and I bought a "tested" alt that "tested" good off ebay. It was 450+shipping bucks and the repair was roughly 350 to have it put on. It worked for about a week. Then went out again. Since it took about 3 weeks to get in to the shop initially I was out side the mandatory 30 day warranty and the seller did nothing but blame the bike. Now I'm looking for a new altenator from a decent supplier but that seems to be pretty difficult. Any suggestions to find one under a grand??

I actually have one alt (with a brand new rectifyer) that is off the bike. I'm considering attempting to repair if parts are easier to find.
https://www.ronayers.com/oemparts/a/hon/5053f202f870021c54be6754/alternator $624.60
 
Very few of us have ever seen the alternator on a ST 1300. That's probably a good thing, because as Dave D. and SupraSabre noted above, getting at the alternator requires an extraordinary amount of disassembly of the bike... probably more disassembly than any task other than removing the engine from the motorcycle.

If you live up in the snow belt, are retired and have time on your hands, you have a nice warm garage and a full set of tools, and it's January and you are seeking an interesting maintenance task that will keep you occupied for a few weeks... well, in that case, getting at the alternator is the perfect answer to your mid-winter boredom. On the other hand, if it is Friday afternoon before a long weekend in summer, you are just about to leave on a long-planned cross-country tour and your alternator dies, you can kiss those plans for your long-awaited tour goodbye, you ain't going anywhere this summer.

My guess is that it would take a highly skilled technician who has done the job before about one-and-a half to two full working days to re & re the alternator. The process goes more or less like this:

1) Remove most of the front Tupperware, remove the gas tank and air box. Have a new fuel elbow hose on hand for reassembly later ($17).
2) Remove the throttle bodies, in the process, disconnect just about every hose, cable, and electrical connector you see. Remove the rubber mat (heat shield).
3) Remove the front fender and wheel (optional, perhaps, but it sure does make the job a lot easier), remove the radiator and the thermostat.
4) Remove the alternator.

Now, at this point, your motorcycle is seriously disassembled. If you are doing this in January with two feet of snow outside, there are a whole bunch of other preventative maintenance tasks that it makes great sense to carry out at this time, including:

5) Clean out all the crud that has accumulated in the V between the cylinders, and make sure the drain path from the V down to the 'square hole' is unobstructed.
6) At a minimum, tighten all the clamps on the coolant hoses in the V. For greater peace of mind, replace the 2 larger-size hoses on the thermostat (about $30) and the thermostat itself and accompanying O-ring (another $30). Might as well order a new air filter at the same time, since you have it out ($35).
7) Wash out all the bugs & dirt from the radiator, now that it is removed from the moto.
8) Lubricate the throttle cables & front moving parts on the throttle body.
9) Check the valve clearances, because at this level of disassembly, it is really easy to get the valve covers off, and really easy to get access to the right side cam chain tensioner.
10) Remove the galley oil plug (the 'mystery plug') and re-install it, this time with a little bit of gasket sealer around the top flange of the plug.
11) Since the front wheel is off... how are the front brake pads?

Once you have dealt with the alternator (replaced it or repaired it, as the case may be) and begin to re-assemble everything, plan to do a throttle body synchronization before you put the airbox back on the motorcycle. You'll need a manometer to do this.

To successfully complete a major project like this with minimal frustration and maximum satisfaction, there are a few things you will need to have on hand before you start work:

a) a Honda Service Manual for the ST 1300, updated with the latest revisions (see here for the revisions: Revisions (Error Corrections) to ST 1300 Service Manual). This is essential, if for no other reason than access to the torque values & re-assembly instructions.
b) a torque wrench (essential for this level of disassembly)
c) easy access to your favourite internet parts provider's web diagrams (for example, Partzilla or similar) - this to enable you to see all the various O-rings, gaskets, and crush washers you will need to order ahead of time.
d) a full jug of replacement coolant (available from any Honda automobile dealer)
e) a full bottle of low-strength Loctite for use when reassembling everything.

Below are a couple of pictures that show the alternator in the V of the engine, after all disassembly has been done except for removing the alternator itself.

Michael

Alternator from above
Alternator 1.jpg

Alternator, viewed from the front looking aft
Alternator 2.jpg
Thanks for all the detailed pictures and recommendations. I am tackling this with a fellow ST owners Member
 
Congratulations, that is an involved job.

My alternator suffered a similar failure at 106,000 miles but there was no way I was spending 10 hours labor replacing just the rotor and putting it back together with used bearings and brushes. The new OEM alternator was $509.00 at that time. While I had the alternator and throttle bodies out I also replaced all the coolant hoses.
Are they not brusheless?
 
This Monday, I am starting to replace an alternator on a friend 04 ST with 120K.
Now that I have learned that alternators on ST have brushes, I am wondering if it is the most common point of failure on these alternators?
It could be worth opening it and have a look inside instead of preventively ordering a new one , that would be $100 versus $700!
Any clues?
 
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This Monday, I am starting to replace an alternator on a friend 04 ST with 120K.
Now that I have learned that alternators on ST have brushes, I am wondering if it is the most common point of failure on these alternators?
Mine was a broken wire in the rotor winding. The brush assembly is about $30, the rotor $330. You can check the rotor continuity in about 30 seconds once the alternator is out. You are a good friend to help out this job.
 
This Monday, I am starting to replace an alternator on a friend 04 ST with 120K.
Now that I have learned that alternators on ST have brushes, I am wondering if it is the most common point of failure on these alternators?
It could be worth opening it and have a look inside instead of preventively ordering a new one , that would be $100 versus $700!
Any clues?

Sidekick. I just installed a new alternator in my 2006. Let me know if you'd like any assistance.
 
Ok, done successfully with my friend chrisemme1!
Just finished replacing the alternator on a 04 ST, in 2 days and 4 hands. The hardest part was the throttle removal and reconnecting all these hoses at the right locations.
Maybe two things worth sharing. Put stickers, or use paint marker on everything you remove, take photos. It will save you a lot of time and frustration when reassembling.
How many hoses, connectors, clamps, where must they be routed, that's a lot of things to remember, my very bad!
No need to remove the cables bracket, just lift the throttle and attach it to the handlebar.
No need also to remove the oil pressure sensor, removing the Philips screw on the top of the sensor will give you enough room to pull the alternator.
If you ever thought about replacing all the coolant and vacuum hoses, this is the right time to do it.
I have learned a lot in the process and I don't think I could have done it without all the information available on the board and the help of the members.
Thank you all!
 
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