Checking and disassembling alternator

[Rick in NYC]

On Saturday, my wife on her Burgman 400, and me on my 1996 VXII was traveling from NY to Cape Cod, Mass. for weekend getaway. It was a sunny afternoon and I was 4 hours/210 miles into my trip. The bike was running great and I was saying Life is Good. Suddently I watched in horror as my voltmeter went from 13.5 volts to 11.6.



I immediately turned off the radio, CB, GPS, foglights, headlight and running lights. In case some of you have never turned off the headlight, here is how to do it: Start the bike in neutral. With your right hand, rev the motor slightly, at the same time, with your left hand, turn your ignition key from run, to accessory, back to run quickly. The bike will stay running with no lights on. To put the headlight back on, tap the Starter button. Althought the voltage went up to 11.8, it did not increase when I reved the motor; I knew I had a bad alternator.

I pulled off the highway into a Shell gas station. Although they had gasoline and coffee, they did not have any repair facilities. I left the bike there and continued to the Bed and Breakfast in Cape Cod on the wife's Burgman.

I called my brother Frank for help. He removed his alternator from his 1997 VXII and drove to my location Sunday morning.



A quick check with a voltmeter confirmed no voltage output. To remove the alternator, remove screws on chrome cover and 3 mounting bolts. You also need to remove the coolant bottle to get at the connector plug.




Be carefull not to lose the 4 black plastic coupling pieces.



With the bike now running, I continued to Cape Cod. Had a wonderfull time in this charming seaside community.



The lighthouse at Chatam Harbour.



Back home I took apart the alternator. Use rag to hold fins from spinning, remove center bolt.



Remove 4 screws underneath.



Next use a new #3 tip philips screwdriver to remove stubborn case bolts.



Scratch a mark on the case for correct re-assembly.



Split the case.



Remove 4 screws to voltage regulator and rectifier.



Use soldering gun to detach 3 soldier joints from stator windings to rectifier.



I used a ohm meter to test the resisters: they were all to factory specs.

I then tested the rotor coil slip rings. I found the cause of the no voltage output. It had an open wire in the rotor windings. See the voltmeter reading's kiss of death: O.L.



I reassembled the alternator and brought it to a local alternator shop. The repairman stated Mitsubishi alternators are notorous for rotor failings. Time to call Carl Leo for a used alternator........

[frank in ohio]

Rick, a few questions. First of all, nice post, nice pictures, good for future reference. How many miles on the bike? Are alternator failures common for the Voyager with your amount of miles. Where did you get the voltmeter and how is it mounted/connected. It appears from the photos that you must have drilled some holes in the fake tank, because there surely aren't any obvious wires.

thanks
frank

[Charlie from Illinois]

Very fine job of documenting the procedure Rick. Thanks. I saved it to my computer.

[Rick in NYC]

My motorcycle has 31,000 miles. I bought it used so I don't know if its true.

I bought the voltmeter from Datel . Its a bit pricey at $50. but its waterproof and professionally made.

http://www.datelmeters.com/cgi-bin/webs ... eacdc.html

To install the voltmeter, remove 4 screws holding cruise panel under false tank. Make a small hole in the tank.



Under the cruise control, I made a second small hole for the voltmeter, and had to carefully cut away some of the bass colored metal for it to fit.

.

My brother has a blue 4 digit readout on his motorcycle. I have a 3 digit red readout.



At first I took power from the cruise control wire. I then noticed that when the cruise was activated, the power went off. In addition, it wasn't a true reading. It was one volt lower then at the battery terminal. I found another terminal with a true reading. If you need to know, I will look up the hookup location.

Anyone know if the alternators are prone to failure?

[bikerking.biz]

I don't think the alternators are particularly prone to failure. I've had mine now for about 75,000 miles. I did have to have the brushes replaced once, but that seems to be normal. The more draw you have on the alternator with additional lights etc. may wear the brushes sooner. It appears that you should check your brushes at about 60,000 or slightly less miles under normal use to make sure they aren't ready to give up the ghost at a bad time. I would imagine using LED bulbs instead of regular ones may reduce the drag on the alternator and prolong the life because of that.

[TaiwanJohn]

You don't need to "remove the coolant bottle to pull the connector plug". Just remove the wires from the back of the alternator.

[Aarowm]

Where can I find the specs for each of the components?

[SgtSlag]

I converted all lights, except the instrument bulbs, to LED's several years ago. My Voltmeter reading increased by just over 1 Volt. I connected mine directly to the battery posts. Mine is an OOP unit, which monitors the voltage drop on the battery, every time you start the bike. It has an LCD display which alternates between the Voltage, and the percentage of battery life left. It saved us 100 miles from home on a trip several years ago -- the low battery life alarm went off when we stopped to change drivers, didn't dare shut the bike off as it likely would not be able to start up again. Pulled into a Kawasaki dealership for a new battery just before they closed. They installed a new AGM for us, and it is still in the bike, today (reading 41% life left in it -- may need a new battery next year).

I check the Voltmeter reading periodically, when riding, to see that the charging system is working properly. The unit has audible alarms for both Low Life Percentage Reading, as well as Low Voltage Readings, but when riding, I doubt we could hear it.

The maker stole the Percentage Life technology from another company. They were caught, and the court forced them out of business due to the reparations required. I got mine right before they went out of business, taking all stock off the market. Hate to think about this unit breaking -- it is around 10 years old, but still working just fine. So far... Cheers!