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RB340 Voltage Regulator Puzzler ?

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healeynut

healeynut

Jedi Knight
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When I start my car after it's sat a couple of hours, the voltage regulator stops working. These are the symptoms:

1) When I start and then run the car, the red generator warning light on my tach will stay more or less on.

2) However, if I blip the throttle and rev the motor to about 4.5K RPMs or more (close to redline), the light will go out and the generator will start charging properly.

3) After I rev the motor to these high RPMs just for a short second as in step #2, the Voltage Regulator will then work correctly for the rest of my drive, and the light will stay off as it should.

4) Interestingly, after the charging circuit starts working, if the RPMs drop to 550, the red light will come back on (as expected) ... but the light will go out again with higher RPMs (as expected).... what I'm trying to say is once the VR starts working, then it works normally even if the charging circuit cuts out for a second at low RPMs.

My question is - can I fix the regulator by popping the cover and filing / adjusting some contacts or is there something more to this I should look at? Also, what should the contact gap be for the voltage cutout relay and the amperage cutout relay?

Thanks in advance! /bcforum/images/%%GRAEMLIN_URL%%/savewave.gif
 
Hi Alan,
One thought I had is the generator itself. Maybe the brushes are sticking and it takes the high revs to break them loose.
 
Hi Alan,
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif--However, if the Control box is old and the contacts are severely burned I would replace it with New. Cleaning of the contacts is possible but based on my experience it is only a temporary remedy--Fwiw--Keoke
 
Had similar expereince on Healey..if you have an older separate adjustable regulator.....the workshop manual actually does a good job explaining what each of the adjustment screws accomplish...only suggestions is make any changes in small graduations to where you need the end resolution...and a drop of locktite to keep it set...
twisting the amps output up even slightly to much can fry your wiring....if it smells or feels hot back if off a hair..but with patience I was able to get the Healey charging as she should....REGARDS!
 
They only cost a Dollars or Pounds, not worth trying to repair, just replace it. But don't forget to flash the new one into your system!
 
Clean up and adjust the old but replace it and keep it in the boot as a spare.

Maybe it is alternator time. In which case you no longer need a voltage regulator. Only an empty regulator cover to carry them spare rotors and for boarder crossings.
 
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