3 brush Not Charging

Post Reply
Scrap
Senior Member
Posts: 824
Joined: Fri Jul 03, 2009 7:07 am
Bikes: 1957 FL
1980 FLT
74 FXE
2017 road glide
1971 Bonneville
2021 Ural GU
Location: Pawtucket
Has thanked: 248 times
Been thanked: 124 times

3 brush Not Charging

#1

Post by Scrap »

1957 FL, 6 volt, 3 brush model 52, genuine delco relay, new battery this season from the HD parts counter.
Bike returned to service this year, generator went to an old school armature shop where it was checked and found to be ok. The shop is very familiar with the 3 brush system.

Adjusted the output to about 7.2 volts with the lights on. The Gen. light would only go off with the stock oem switch in position 2 (lights on)
Keep the battery on a battery tender when the bike is in the garage and have only gone on short rides as I have a few things that still need attention before I take it on a long ride.
Today I put a volt meter on the battery after I returned from a short 10 mile ride. With the engine off, 6.2 volts. Engine running and revved up, switch position 1, Gen. light on, 6.2 volts. Switch position 2, lights on, Gen. light off, 6.2 volts, does not budge. I'm confident that I have wired it correctly. Good grounds, all soldered connections. I suppose I may have made a mistake. What would cause the relay to signal the Gen. light to turn off even though the battery does not appear to be charging.
Thanks
awander
Senior Member
Posts: 2082
Joined: Fri Sep 21, 2007 3:03 am
Bikes: '52 FL
'64 FLH
Has thanked: 163 times
Been thanked: 511 times

Re: 3 brush Not Charging

#2

Post by awander »

You need to adjust the generator to a 2-3A charging rate, into the battery, per the manual.

From what I have seen with my voltmeter and ammeter that I installed on my '52, you should pay no attention to the voltage. it will vary from less than 6V up to 8.5V or more while you ride.

Also, do the adjustment of the 3rd brush with the lights off. that will tell you right away if you have a bad field coil.
1950Panhead
Senior Member
Posts: 2404
Joined: Wed Jul 07, 2010 4:28 am
Bikes: 1950Panhead
Location: USA
Has thanked: 1 time
Been thanked: 366 times

Re: 3 brush Not Charging

#3

Post by 1950Panhead »

What would cause the relay to signal the Gen. light to turn off even though the battery does not appear to be charging
Gen voltatage has reached level to connect battery and turn gen light off.
Check battery water level, my guess is gen is ok.
With ligts on you get two field coils increasing gen output.
Jerry
Scrap
Senior Member
Posts: 824
Joined: Fri Jul 03, 2009 7:07 am
Bikes: 1957 FL
1980 FLT
74 FXE
2017 road glide
1971 Bonneville
2021 Ural GU
Location: Pawtucket
Has thanked: 248 times
Been thanked: 124 times

Re: 3 brush Not Charging

#4

Post by Scrap »

awander wrote:You need to adjust the generator to a 2-3A charging rate, into the battery, per the manual.

From what I have seen with my voltmeter and ammeter that I installed on my '52, you should pay no attention to the voltage. it will vary from less than 6V up to 8.5V or more while you ride.

Also, do the adjustment of the 3rd brush with the lights off. that will tell you right away if you have a bad field coil.
OK, is it correct to assume when I initially adjusted the output of the genny while measuring voltage, the battery was low and therefore I was able to increase the measured voltage as I adjusted the third brush? Now is it correct to assume the battery is up so I'm not seeing any increase or decrease over the 6.2 volts I measured running at idle, revved up and engine off? My next step is to measure the amperage in series with the battery. My meter has a 10 amp scale, it is fused so I guess I won't burn it up, but what is possibility of exceeding 10 amps while I fiddle with the third brush? Do you think the alligator clips on the meter is sufficient or is a more secure connection required to get a good reading? I just was puzzled by the fact that the battery voltage is the same regardless of the engine running or stopped.
Thanks
awander
Senior Member
Posts: 2082
Joined: Fri Sep 21, 2007 3:03 am
Bikes: '52 FL
'64 FLH
Has thanked: 163 times
Been thanked: 511 times

Re: 3 brush Not Charging

#5

Post by awander »

You could get over 10A, but if you are careful you should stay below that, and not have to replace your meter's fuse.

I am confused about where you measured the 7.2 volts, if the battery stays at 6.2 no matter what.

If the battery is low on charge, you will see LESS voltage across battery for a given amount of current into battery. As the charge level on the battery comes up, then the voltage will also rise, for the same amount of current in.


If you do as I have done, and actually wire an ammeter into the bike, so you can view current into battery and voltage across battery while riding, you will find that battery voltage actually varies wildly while riding, from 6V or so up to 9V at times. This seems to have to do with many factors, such as whether the engine is hot, how fast it is turning, possibly the phase of the moon.....:) All of this while the current varies between 3A and 6A.

Alligator clips are sufficient for a test, though I wouldn't recommend using them while riding.

Oh, another thing I have found, merely revving the engine does NOT seem to give a good reading; it seems like you have to actually be riding the bike. No idea why that would be true....I don't have a tach, d=so I am not sure if I am revving it to the same speed that I get during a ride.

Are you sure your relay is closing? Maybe a bad contact? There are 2 separate contacts in the relay, one that opens to turn the light off, and one that closes to actually connect the generator to the battery. If the main contact is bad, the idiot light will go out, but the battery will never charge.
nmaineron
Site sponsor
Site sponsor
Senior Member
Posts: 653
Joined: Sun Oct 17, 2010 1:00 am
Bikes: 1995 fxsts,1963 fl project in progress
Location: Patten,maine
Has thanked: 120 times
Been thanked: 98 times

Re: 3 brush Not Charging

#6

Post by nmaineron »

It sounds to me that you are only getting battery voltage simply because you have no change in output,sounds like current is going to ground which would mean that your system is not polarized ..just a seat of the pants guess with a little experience thrown in...I am hardly an electrical wizard..so it would be my move to recheck your relay connections as well genny connections...you should polarize your system every time you disconnect the battery or any connection on the genny or relay...

your only going to produce voltage from the genny...amps are measured by the load in the system such as lights,horn and accessories that are using the voltage so in order to test for amps you have to put a load on the system...
john HD
Moderator
Senior Member
Posts: 3711
Joined: Mon Dec 01, 2003 11:38 pm
Bikes: '42 WLA X 2, '55FL, '93 Ultra Classic, '91 Fatboy, '97 883, '03 Rokon Trailbreaker, '83 GPz 750.
Has thanked: 70 times
Been thanked: 128 times

Re: 3 brush Not Charging

#7

Post by john HD »

If the main contact is bad, the idiot light will go out, but the battery will never charge.
andy hit it right on the head.

check your relay terminals first.

john
Scrap
Senior Member
Posts: 824
Joined: Fri Jul 03, 2009 7:07 am
Bikes: 1957 FL
1980 FLT
74 FXE
2017 road glide
1971 Bonneville
2021 Ural GU
Location: Pawtucket
Has thanked: 248 times
Been thanked: 124 times

Re: 3 brush Not Charging

#8

Post by Scrap »

Thanks for all the replies.
After the initial start up, I measured the voltage at the battery. I had definitely polarized the genny and I was able to vary the voltage as a function of the 3rd brush position. Now that I don't see any "charging" voltage, the relay will be the fist thing I check. If I need to replace it, does anyone have a recommendation? How about a solid state unit?
Thanks,
Sam
john HD
Moderator
Senior Member
Posts: 3711
Joined: Mon Dec 01, 2003 11:38 pm
Bikes: '42 WLA X 2, '55FL, '93 Ultra Classic, '91 Fatboy, '97 883, '03 Rokon Trailbreaker, '83 GPz 750.
Has thanked: 70 times
Been thanked: 128 times

Re: 3 brush Not Charging

#9

Post by john HD »

sam,

before you change the relay take a business card soaked with electrical cleaner and work it between the contacts. pushing down slightly while working the card back and forth helps.

there are relay adjustment instructions in the knowledge base.

john
Scrap
Senior Member
Posts: 824
Joined: Fri Jul 03, 2009 7:07 am
Bikes: 1957 FL
1980 FLT
74 FXE
2017 road glide
1971 Bonneville
2021 Ural GU
Location: Pawtucket
Has thanked: 248 times
Been thanked: 124 times

Re: 3 brush Not Charging

#10

Post by Scrap »

john HD wrote:sam,

before you change the relay take a business card soaked with electrical cleaner and work it between the contacts. pushing down slightly while working the card back and forth helps.

there are relay adjustment instructions in the knowledge base.

john
Thanks for the tip
nmaineron
Site sponsor
Site sponsor
Senior Member
Posts: 653
Joined: Sun Oct 17, 2010 1:00 am
Bikes: 1995 fxsts,1963 fl project in progress
Location: Patten,maine
Has thanked: 120 times
Been thanked: 98 times

Re: 3 brush Not Charging

#11

Post by nmaineron »

Scrap,for what its worth..I took an after market relay and robbed the points off it and put them into the old relay and had good luck with it...
awander
Senior Member
Posts: 2082
Joined: Fri Sep 21, 2007 3:03 am
Bikes: '52 FL
'64 FLH
Has thanked: 163 times
Been thanked: 511 times

Re: 3 brush Not Charging

#12

Post by awander »

Those relays are tough little buggers. I can fix yours if it is busted.
1951 adam
Senior Member
Posts: 889
Joined: Mon Apr 02, 2012 5:35 pm
Bikes: 1951 panhead , 1995 dyna
Has thanked: 116 times
Been thanked: 47 times

Re: 3 brush Not Charging

#13

Post by 1951 adam »

Check your voltage output from the gen to relay terminal, also the battery in a 3 brush system acts as its voltage regulator, the contacts will open and close the circuit dependent on battery voltage or generator output. if you read the service manual there is a test for the relay, I used an ohm meter but a 110 v test lamp works great. I used a reproduction delco 3 brush relay, and it worked fine after I set the points, and fixed a broken fine shunt wire. I found an original and am using it now. The system works great but you really need to take the time to set everything up correctly, and check the battery with a hydrometer, because it may seem fully charged but the S.G might be low in the cells, GOOD LUCK! Adam
Scrap
Senior Member
Posts: 824
Joined: Fri Jul 03, 2009 7:07 am
Bikes: 1957 FL
1980 FLT
74 FXE
2017 road glide
1971 Bonneville
2021 Ural GU
Location: Pawtucket
Has thanked: 248 times
Been thanked: 124 times

Re: 3 brush Not Charging

#14

Post by Scrap »

It's been too hot to go in the barn, the weather has finally broken and I can get to work. Thanks to all for all the feedback. Always a wealth of knowledge on this site.
Sam
Scrap
Senior Member
Posts: 824
Joined: Fri Jul 03, 2009 7:07 am
Bikes: 1957 FL
1980 FLT
74 FXE
2017 road glide
1971 Bonneville
2021 Ural GU
Location: Pawtucket
Has thanked: 248 times
Been thanked: 124 times

Re: 3 brush Not Charging

#15

Post by Scrap »

OK, here are the readings on my ammeter:
High Beam on, 2000 RPM: 4.0 amps, Gen. Light Off
High Beam on, idle: 7.2 amps, Gen. Light Off
Lights off, switch position 1, 2000 RPM 1.5 amps, Gen. Light On.
Lights off, switch position 1, idle: 1.5 amps, Gen. Light On.
With the lights on, when I rotate the third brush, I can increase or decrease the amperage. As I increase the RPM's, the amperage drops off in direct proportion to the increase in RPM's.( I can get it below 2 amps)
With lights off (switch position 1) the amperage reads 1.5 amps regardless of the position of the the third brush or the RPM's, constant 1.5 amps and the Gen. light is lit.

Is something wrong with one of the two field coils? If so, why does it put out a constant 1.5 amps no matter what I do? I have not touched the the cut out relay yet. Do any of these readings point to the relay? The genny was given the OK by an armature shop. Would it be normal for the Gen. light to be on with a positive 1.5 amps going to the battery? If the battery serves as the voltage regulator on three brush systems, could my battery be an issue? I feel pretty confident that I have good grounds and good soldered connections on my wiring.

When this bike was my regular ride, the Gen. light was inoperative, and I never suffered from any charging problems and I didn't have the benefit of the internet to make me worry about things I was ignorant of.

Please advise
Thanks,
Sam
Post Reply

Return to “Generator”