54 FLH gen light

Electrical issues
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panman76
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54 FLH gen light

#1

Post by panman76 » Wed Oct 31, 2012 2:50 pm

Hey whats up fellas? I got a 54 pan running a 32E syock 6 volt genny with a voltage regulator eliminator. Been running this way for 35 years. Had engine rebuilt put back togatheralls well. Was going out driveway and it started popping and shooting like it wasnt charging,turnedv around and went back to the shop and noticed a faint flickering of the gen light. Well i figured since we had had this thing since 72 and it had never had any genny work it was due time. I took it off and took it to a cat that does rebuilds. He tore it down and could find nothing wrong,he cleaned it up,reassembled it and sent me on my way. Reinstalled and fired it up,with a new regulator eliminator,same problem,faint glow at idle and when accelerated the light gets brighter. Tried a new battery,same problem. Tried to polarize the genny same problem. Should I have disconnected the battery before trying to polarize the genny since I didnt polarize it prior to running the scoot? Any ideas would be greatly appreciated!!!!!!!



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Re: 54 FLH gen light

#2

Post by Scrap » Wed Oct 31, 2012 6:50 pm

What's a voltage regulator eliminator? Didn't it just have a cutout relay originally? Is still a 3 brush generator or was it ever converted to 2 brush?

jdpan
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Re: 54 FLH gen light

#3

Post by jdpan » Wed Oct 31, 2012 10:43 pm

If I remember correctly, a regulator eliminator is a Zener diode placed on the hot wire at the battery to allow power to flow in one direction only. They are at a set value specificly for this application... I used to run one on my old '57 chop and I think I might even still have it along with an entire 6v system.

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Re: 54 FLH gen light

#4

Post by Scrap » Thu Nov 01, 2012 3:14 am

jdpan wrote:If I remember correctly, a regulator eliminator is a Zener diode placed on the hot wire at the battery to allow power to flow in one direction only. They are at a set value specificly for this application... I used to run one on my old '57 chop and I think I might even still have it along with an entire 6v system.
Ok, I have one on my Triumph, never saw one on a pan.

DuoGlide62
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Re: 54 FLH gen light

#5

Post by DuoGlide62 » Thu Nov 01, 2012 6:34 pm

I'd check your grounds.

awander
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Re: 54 FLH gen light

#6

Post by awander » Thu Nov 01, 2012 8:35 pm

The cutout relay eliminator(not a voltage regulator eliminator) is not a Zener Diode(those are used to regulate voltage) but just a regular diode. It serves the same purpose as the cutout relay, preventing the battery from discharging through the generator, when the generator is not producing enough voltage to charge the battery.

The thing is, when you install that diode, there is no connection for the generator light.

In the stock '54 wiring, one side of the generator light is tied to + at the dash, and the other side of the light gets a switched ground from the cutout relay. When the relay drops out, it grounds the light, lighting it up.

A common way to hook up the light is to take the wire that used o go to the cutout relay and tie it to the output of the generator. That way, when the generator voltage is at or near battery voltage, the light will have essentially the same voltage on both of it's connections, and won't light up, or will light only dimly. When the generator voltage drops far enough, the light will light.

Sounds like your electrical system is working the way it should. i would look elsewhere for the running problem. The fact that the light gets brighter when you rev it might mean it is hooked up differently(maybe the dash side of the light is grounded?), or you may have a problem in your ground connections, as already suggested.

Regarding disconnecting the battery before polarizing the generator, that will not do any good. the battery must be connected for polarizing to work at all.

Panhead Ed
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Re: 54 FLH gen light

#7

Post by Panhead Ed » Fri Nov 02, 2012 12:30 pm

as prior post suggest check your ground connections ALL of them ! and throw that dam modern diod as far out in the river as you can ! never had one that worked.. Ed

the ground is the most overlooked connection . yea its grounded is not the right mind set.

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Re: 54 FLH gen light

#8

Post by Scrap » Fri Nov 02, 2012 6:43 pm

Panhead Ed wrote:as prior post suggest check your ground connections ALL of them ! and throw that dam modern diod as far out in the river as you can ! never had one that worked.

He said it worked great for 35 years...but I'm curious, if, as a diode or a "one way electrical valve", it prevents the battery from discharging, how did this system prevent the battery from overcharging? Is there more to it than just a diode?
Ed

the ground is the most overlooked connection . yea its grounded is not the right mind set.

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Re: 54 FLH gen light

#9

Post by Scrap » Fri Nov 02, 2012 6:46 pm

Panhead Ed wrote:as prior post suggest check your ground connections ALL of them ! and throw that dam modern diod as far out in the river as you can ! never had one that worked.. Ed

the ground is the most overlooked connection . yea its grounded is not the right mind set.
I messed up my quote on the last post, this is my only question.

He said it worked great for 35 years...but I'm curious, if, as a diode or a "one way electrical valve", it prevents the battery from discharging, how did this system prevent the battery from overcharging? Is there more to it than just a diode?
Ed

awander
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Re: 54 FLH gen light

#10

Post by awander » Fri Nov 02, 2012 7:23 pm

Ed:

A 3-brush generator and cutout relay setup has no mechanism to prevent the battery from overcharging.

The 3rd brush on the generator is used to set the charging rate, which H-D recommends should be 3-4A into the battery.

From what I see on my bike, with an installed Voltmeter and Ammeter, that rate fluctuates wildly with engine speed, engine/generator temperature, battery state pf charge, and possibly phase of the moon.

Substituting a diode for the cutout relay doesn't really change things, except that the diode drops about 0.7V, so the generator will need to be adjusted to keep charging rate the same.

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