Author Topic: Too much voltage, bad rectifier?  (Read 2632 times)

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Offline Artfrombama

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Too much voltage, bad rectifier?
« on: November 24, 2008, 12:57:50 PM »
One of my other bikes (Honda CL 100) seems to be overcharging the battery. Could this be a bad rectifier?
6V system, when I rev the engine I get almost 10V. (reading taken @ battery)
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Offline kirkn

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Re: Too much voltage, bad rectifier?
« Reply #1 on: November 24, 2008, 01:24:09 PM »
Wow, I'd have bet money that there's no way an old Honda 6-volt system could put out that voltage connected to a 6-volt battery.  The only way I'd expect to see 10 volts at the battery with engine revved up would be to hook it to a 12-volt battery...  :)

Kinda like the joke - "How do you make a small fortune in the commodities market?  Start out with a large fortune"

Seriously, though, the rectifiers don't do any regulating at all, so about the only way you could get that voltage is if one leg of the bridge shorted across (and I've never heard of one failing this way) and you were reading the AC voltage direct from the alternator.

Keep us posted with what you find.

Kirk


Offline TomC

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Re: Too much voltage, bad rectifier?
« Reply #2 on: November 24, 2008, 06:02:15 PM »
Hi Artfrombama
     I have seen 17volts in to a capacitor from my Super 90 kicking it over.
     The rectifiers are always suspect. But I would suspect your battery. Also does your CL100 have any burned out bulbs.
          TomC in Ohio
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Offline Artfrombama

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Re: Too much voltage, bad rectifier?
« Reply #3 on: November 24, 2008, 06:45:29 PM »
Hi Artfrombama
     I have seen 17volts in to a capacitor from my Super 90 kicking it over.
     The rectifiers are always suspect. But I would suspect your battery. Also does your CL100 have any burned out bulbs.
          TomC in Ohio
When I got it someone had stuck in a 12v headlight. I replaced it with the correct one. Tail light was missing. Blinker relay was not working.

When I got the bike it had no battery. I bought a new cheepie (Bikemaster) battery, filled it with acid and slow charged for 3 hours.

When I got the thing running I could smell the battery cooking.
That's when I got the battery voltage readings.

All the bulbs are very bright. Too bright for a 6V system.

Scored a used rectifier on eBay.
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Offline bryanj

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Re: Too much voltage, bad rectifier?
« Reply #4 on: November 24, 2008, 08:41:45 PM »
It aint the rectifier as that does not REGULATE the voltage/ Would have to look closely at wiring diagram(which i aint got sorry) to try and sort out what is going on
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Offline HavocTurbo

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Re: Too much voltage, bad rectifier?
« Reply #5 on: November 24, 2008, 09:27:09 PM »
« Last Edit: November 24, 2008, 09:29:28 PM by HavocTurbo »
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Offline TomC

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Re: Too much voltage, bad rectifier?
« Reply #6 on: November 25, 2008, 07:24:49 AM »
Hi Artfrombama
     "Scored a used rectifier on eBay."
     When I said that rectifiers are always suspect used rectifiers from ebay are in particular suspect. I would not use an original rectifier. I purchased a modern silicon bridge rectifier, 35A 400V, for $3.95 for my Super 90.
     Rectifiers are not that hard to test. I use a test light not an ohm meter. The rectifier has four diodes in it. You need to test each diode. Current should flow in one direction and not in the other direction.
      TomC in Ohio
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Offline Artfrombama

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Re: Too much voltage, bad rectifier?
« Reply #7 on: November 25, 2008, 02:37:41 PM »
I saw those silicon rectifiers on eBay but was afraid of getting sc***ed again on eBay. Scored a OEM for $5., if it's no good, not out a lot of cash....
Hi Artfrombama
     "Scored a used rectifier on eBay."
     When I said that rectifiers are always suspect used rectifiers from ebay are in particular suspect. I would not use an original rectifier. I purchased a modern silicon bridge rectifier, 35A 400V, for $3.95 for my Super 90.
     Rectifiers are not that hard to test. I use a test light not an ohm meter. The rectifier has four diodes in it. You need to test each diode. Current should flow in one direction and not in the other direction.
      TomC in Ohio
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Offline Artfrombama

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Re: Too much voltage, bad rectifier?
« Reply #8 on: November 25, 2008, 02:40:37 PM »
Halfassed machinist
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CB750-2011594 Sunrise Flake Orange
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