Voltage regulator/rectifier and battery

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mcgovern61

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Location
Kingsport, Tennessee
My Bike Models
Former '82 GL1100 "The Slug"
My battery died over the winter (As expected). It was 2 years old, but I did drop the bike once and had acid leak out. I put distilled water back in, but it keeps boiling out? I have had to add water often. I had stator issues because I had tried to fix the wires with compression/spade connectors. Last summer I finally cut the wires and soldered them. The battery voltage went up to and stays at 15.2 volts after 2000 rpm. I assumed that was pretty high.

Now I have a new engine (and stator) and soldered the wires right up front. Added water to top off the battery again and ran the engine. It is still charging up to 15.2 volts. I had a spare voltage regulator and swapped it. Still 15.2 volts. I checked my Haynes and Clymer and it appears that 15.0 volts is normal?

If it is normal, why am I losing so much water? (Cheap battery?) I am going to replace the battery with an AGM but wanted to be sure that the voltage is right. I do not want to ruin a new battery.

Any ideas?
 
A loose ground at the frame could cause this.
There is only one ground connection from the factory, at the front coil bolt.

Otherwise it sounds like a bad regulator unless your meter is reading high.
The highest it should ever get is 14.8, higher will boil the battery dry.

If I had known I would have thrown one in the box with the mufflers.
 
mcgovern61":1ni0z5y2 said:
Thanks Dan, I'll check the ground and see if I have a good connection. Two regulators both running up to 15.2?


or a faulty meter just not accurate enough?? both read the same.. try another meter just to eliminate that as an issue..
 
Joep":1ldnptph said:
mcgovern61":1ldnptph said:
Thanks Dan, I'll check the ground and see if I have a good connection. Two regulators both running up to 15.2?


or a faulty meter just not accurate enough?? both read the same.. try another meter just to eliminate that as an issue..
Joe, I was thinking your way too! I was hoping that my digital multi-meter was off by 2 volts, so I used my analog multi-meter and it gave the same result. I brought home a calibrated multi-meter from our engineer's office and it also shows 15.2 volts at the upper end. I guess in one sense it is good to find out that my multi-meters are accurate, but it doesn't help my regulator.

There is not much more load than a GL1100 standard, headlight, sparkies, tail light and two side markers in the front turn signals plus my radio.
 
well gerry at least you know that the sator is good and thats very good news , ithink mines the same way when the battery gets some age it starts boiling out the water its time for new batt mine runs upward to 15 volts but gas gauge and water temp seem fine . id say its time to try the gel batt for you and me
 
I was about to go out and test the rectifier when I realized that I had to take the tank off. :Awe:
That also means the faring, seat and bags. I decided to go for a ride instead and took my 12 year old mechanic daughter for a victory ride for helping put the engine in! :clapping:

When we got back, the voltage was 12.6 at idle but 15.66 at 4000. It will cook the battery. However, the old one charged up while running and its holding from day to day so for now I will just keep adding water until I can pull the tank and check the rectifier.

BTW, I love the smell of fresh engine paint getting hot and setting in!
 
One of the things I did was add an analog voltmeter to my bike down in the faring where I can keep an eye on the voltage. The bike keeps starting up and running ok, so until I lose the battery I will keep using it. I have been able to make some interesting observations. When riding in stop and go traffic, it will go as low as 11.9 volts with the fan running at a red light (950 rpm idle) and up to 15+ when up to 4000 rpm between redlights. Yet when we took our 150 mile trip this weekend, it stayed at 14.6 and when travelling at 75 MPH and about 4200 rpm. Now, I cannot see why it would be different at the same or higher RPM except maybe the coils are under a greater load when the bike really is at speed?

Another observation. I raised the idle to 1100 and now it doesn't go below 12 volts when stopped, hot and the fan is on. The stator does work pretty good, but I am just trying to wrap my mind around this RR.
 
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