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Generator test/horn short

Electrical issues
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jd222
Posts: 28
Joined: Sun Apr 02, 2006 12:05 pm

Generator test/horn short

#1

Post by jd222 » Wed Aug 09, 2006 4:51 pm

Hey guys..what's the easiest (read:simple) way to test with my multimeter if the gen in my 59 FLH is putting out enough juice? I took it to the Yankee Chapter AMCA NAtional meet this past weekend- about 90 minutes each way, and it ran fine but yesterday I went to get on it and the battery was dead.
My guess is a short and not the generator, as there seems to be a problem under my dash with the terminal the horn is wired to touching the dash (the light shields I think) as on occassion, if I tighten the dash down tight the horn will sound until I back off the nut. I've tried bending the shields a little, insulating the wire and nut, but it still seems to eventually short. I want to eliminate the gen as a cause before I start on the wiring, although I would guess this might be the problem. Any suggestions to remedy this short, or if anyone else has experienced this, I'm all ears!

Thanks for the help
Joel



Sidecar
Posts: 272
Joined: Tue Apr 17, 2007 9:21 pm
Location: Southwestern, Pa.

Re: Generator test/horn short

#2

Post by Sidecar » Wed Aug 09, 2006 7:11 pm

* Put the tester in DC mode.
*Observe polarity and connect it to the pos & neg terminals on the battery. * Note the voltage. ( should be around 12 )
* Start the bike and rev it up a little.

If the genny is working correctly the voltage will go up. ( 13+ volts )

Are you sure that your battery is still good ?

King
Posts: 387
Joined: Fri Apr 02, 2004 5:05 pm

Re: Generator test/horn short

#3

Post by King » Wed Aug 09, 2006 10:16 pm

I'm going through a similar thing. Battery discharges over a period of a week or so even though I'm putting about a half hour on the bike every day. The GEN light never fully goes out it sort of glows and flickers. I think the genny is OK being rebuilt by Dale Cashman not too long ago and I sort of suspect the cut-out relay isn't allowing enough current to go to the battery to keep it charged.. The relay is ancient, and although I've cleaned it and set its gaps, age may have taken its toll.

So question is, how do you test the generator (32E, 6V) in isolation from the relay and battery?

Thanks

King

jd222
Posts: 28
Joined: Sun Apr 02, 2006 12:05 pm

Re: Generator test/horn short

#4

Post by jd222 » Wed Aug 09, 2006 11:52 pm

The battery is brand new this spring and is on a trickle charger whenever the bike is parked- I charged it last night and it's full and strong (12+ volts). I think it must be a short although I';ll test the gen as suggested and see what it's doing. The horn thing seems to be an obvious problem that needs to be addressed and would seem a likely draw on the battery. I was hoping someone else had the same problem and had a fix. I would like to move the horn lead to a "key on" terminal..any suggestions which to use?

Thanks
Joel

mbskeam
Posts: 1004
Joined: Tue Mar 16, 2004 5:52 am
Location: Sultan, WASH
Contact:

Re: Generator test/horn short

#5

Post by mbskeam » Thu Aug 10, 2006 1:35 am

you can rewire the horn so that it only has power when the headlights are on, but you must fix the live short, as this could lead to a bigger problem....like up in smoke
you can use the meter to find a hot term when the switch is on.

mbskeam

King
Posts: 387
Joined: Fri Apr 02, 2004 5:05 pm

Re: Generator test/horn short

#6

Post by King » Thu Aug 10, 2006 2:46 pm

Regarding horns, does the horn button work on the hot or the ground side of the circuit?
Also I tested my charging circuit last night and got 6.1V at the battery; engine off, engine at idle, and engine reving. So I'm pretty sure no current is being supplied to the battery. At the generator's relay terminal I got 8V at idle and 10+V when reved to about 1900rpm. At the switch terminal I got 0V. My suspicion is that the cut-out relay is boogered. Am I thinking in the right direction?

Thanks

King

Fixman
Posts: 142
Joined: Sun Apr 08, 2007 6:38 pm
Location: Charlottesville, VA

Re: Generator test/horn short

#7

Post by Fixman » Thu Aug 10, 2006 3:14 pm

HI King! I'll try the horn switch question. The horn on the stock setup has two wires. The hot wire to the horn comes from terminal one on the ignition switch while the ground wire is from the handlebar switch. When you push the horn switch, you complete the ground.
My voltage before a ride averages 6.25, and after the ride it is around 6.65. My guess is that you are right in suspecting the relay. I have a solid state one that seems to work great. The third brush on my generator is fully adjusted to the left (least current produced).

P.S. Got my new Firestone replica tire from Coker. Hope it smooths out the front end. Will rebuild the struts when we change the tire.

Kent

fourthgear
Posts: 1390
Joined: Mon Apr 11, 2005 1:12 pm
Location: north florida

Re: Generator test/horn short

#8

Post by fourthgear » Thu Aug 10, 2006 4:51 pm

jdc222
To see if its your horn causing the short & draining your bat. , just disconnect it from the switch and secure it or tape it to keep it from flopping around in your dash and see how it charges or discharges for a period of time.
I don't like any device having power when the ign. switch is off . You can do as mbskeam said and connect it to the light power side of the switch ( if you are having interference with the ind. light shield use ign. switch ,# 2 term. , that would be the bottom one of the two that are in the five o'clock position on the switch as you are looking down at it , # 1 being the one directly next to and above it and where your horn wire is connected to and 12V + from batt. via term. # 39 on the rear term. panel)

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