xj650 Maxim - Regulator not working

1982 650 Maxim has 1,100 miles. It sat for 3 decades and now it's almost completely restored, rides good, it runs good and everything works except it will not charge the new battery I installed. Battery tender keeps it fully charged. Battery tested good at Oreilly's but their test equipment indicated the regulator is bad. I wonder if their equipment is only good for cars, not bikes. They didn't seem to know.

And I wonder if the alternator is not working, yet their equipment indicates it's a regulator issue. Is there a process that I can follow to test my alternator?

Or, can the regulator (rectifier) be bench tested somehow?

Perhaps, if it makes any difference, have my Maxim tested at a motorcycle shop or someplace that deals with bike electrical issues? I'd rather do it myself if I can find some guidelines on how to. I'd really appreciate some advice on this.

 

So my guess is you don't have a shop manual? Digital multimeter? Bike running about 2500 rpm should see 13.8 + volts at battery posts. Double check ground wires from battery and wire harness ground as well. Will get you alt outputs in the morning.

 

do not base anything on what your local auto parts store says.......do not trust their advice at all.........test yourself....

 

Dmm test the stator and rotor as advised. There's also a earth ground separate from the battery ground at the back of the mill. It connects to the frame under the left side cover. Make certain paint is not preventing a good connection. If so it causes all kinds of funny things to happen.

Gary H.

 

link to pdf http://www.tradebit.com/filesharing.php/search/0/1982+650+maxim+service+manual
Service Repair Workshop Manual $8.95

 

Thanks guys! I just realized something, a while ago I replaced an original relay. It's the starter cut-off relay located just below the rectifier. My headlight & gauge lights didn't work until I swapped in another relay. Seemed like a "good fix" at the time, but I have a feeling this incorrect relay may have to do with the charging problem after all.

The original relay was a 3H5-00 05Y1D9. And its marked with yellow paint, I don't know why relays are marked either yellow, or blue or not marked at all. Are there relays that supersede this original? There are a few 3H5-00 ones on ebay, but I don't know if the smaller size numbers (05Y1D9 on mine) need to be matched exactly or what. If not, then perhaps I should take a chance and buy one hoping that's the core problem with my charging issue.

 

The paint color is used as an easy and consistent identifier for the assembly line and for service. Here is the guide that will tell you which relay is which. http://www.xjbikes.com/forums/threads/the-ultimate-relay-switch-sensor-and-diodes-guide.27543/

I doubt very much that the relay is the cause of your charging troubles.

 

So that relay at that location is the headlight relay. What is the number on the one you put in and does it have any color coding on it?

Installing a starter cutoff relay in the headlight relay location could cause bad things to happen to the diode block and the AC Generator.

Per Len's guide:

Location Headlight Relay:
- on all XJ550 models: under the gas tank, in-between the frame tubes, on a welded bracket just behind the flasher self-canceller relay.
- on all XJ650 Maxim/Midnight Maxim/RJ Seca models: behind left side cover, below the TCI and Regulator-Rectifier unit.

Identification Headlight:
- small metal "cube" relay, inked 3H5-00 on the top face.
- has a yellow (yellow) paint mark on the bottom terminal connector block.

Identification Starter Cutoff Relay:
- on all models except XJ700 or XJ750-X models:
- small metal (original) or plastic (replacement) "cube" relay, inked 4H7-00, 4H7-01, or 12R-01 on the top face.

 

Thanks for that! Not sure if my charging issue is cleared up now that my relays are in proper order. My relays were all out of place on the loose wire bundle, my project bike came in boxes and the frame was stripped completely. Now, my kick stand safety switch and clutch lever switch works now that relay 4u8 is in the correct place. 4H7 was taking that spot, until I put it in the correct starter cut-off spot. However, the 3H5 (properly plugged in below my TCI & Regulator) does not let the headlight turn on as it should. I can swap in any relay and the headlight will work, but will not dim when starting. I'll look into troubleshooting that relay further tomorrow.

 

Normally the headlight is off when the ignition switch is turned on because the headlight relay contacts are open.

When the bike starts, one leg of the AC Generator is rectified by the diode block and applied to the coil of the headlight relay, which causes the relay to energize closing the contacts applying power to the headlight. Within the headlight relay is another diode connected so that once the contacts close, power is fed back through the coil keeping the headlight relay latched and the headlight on until power is removed by turning the ignition switch off. The internal diode within the headlight relay is why when the bike almost starts the headlight remains on until the ignition switch is cycled from on to off. A working AC Generator is required to get the process started, so if the AC Generator is totally dead the headlight relay will not be energized and then latched illuminating the headlight.

Note also on correct relay location that the headlight and side stand relay, yellow and blue dots, respectively are easily located by noting the color of the vinyl tape on the main harness and matching that with the colored dot on the relay.

As for no charging, the shop manual has a very detailed test for the AC Generator and Rectifier Regulator. So, best advice is to get a copy of that and go through the steps. If you have any problems or questions just ask.

 

It's ALIVE! Many thanks to you and all the other replies. Great guidance from everyone here, which sort of led me to eventually open up and peek at the stator. I found the copper tracks extremely corroded. Cleaned them up with 32o wet dry sand paper and now the charging system WORKS!