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#1 Adjusting regulator

Posted: Sat Jul 18, 2015 7:28 am
by andrewh
Has anyone experience of adjusting the regulator on the 3.8 accurately? I have a new Old stock unit fitted but it seems to be over charging the battery as I am getting a mist of battery acid on the top of the battery. This is my second rubber cased battery as the first one cracked along the seam on the top which I thought was a fault with the battery, now this one is starting to sweat as well I can only put it down to the regulator not cutting out perhaps. Also how do you get the black plastic cover off with out removing the whole regulator from its bracket?

#2

Posted: Sat Jul 18, 2015 7:43 am
by abowie
The section in the manual on testing the regulator is good. The only problem I had was that I didn't have a beefy enough amp meter.

Given the cost, I have always just replaced them if if I suspect them...

#3

Posted: Sat Jul 18, 2015 7:48 am
by andrewh
Well ok, but the first new regulator I bought would not work at all hence this one sourced off E Bay as a NOS unit, perhaps I now know why it wasn't used! Dumb question time......are they same if the car is positive or negative earth? Must be...it can't be that.

#4

Posted: Sat Jul 18, 2015 8:18 am
by JagWaugh
Andrew,

The mechanical RBs are polarity ignorant. You might want to flash it once you get it installed and connected, but first, take it out, check that all connections are solid (i.e. the rivets, the windings, also check that the nichrome resistor underneath isn't burned out/rusted), dress the contacts, clean it scrupulously, then refit and polarise, then adjust per the manual.

I have a clamp on current probe for my DVM, but I keep a moving coil voltmeter specifically for this task - Digital meters jump around so much that you can't really make sense of them, but with a moving coil meter, even a cheap one, it shows you an average value. Yes, you can get a DVM with a bargraph, but a moving coil instrument is still easier to read.

Andrew

#5

Posted: Sat Jul 18, 2015 8:59 am
by andrewh
Thanks Andrew. I am sure it is working ok but if anything not cutting out when the battery is charged. I need to get an old meter as you point out the digital meters are no good for this. How does the cover come off?

#6

Posted: Sat Jul 18, 2015 9:16 am
by JagWaugh
Andrew,
_Usually_ 2 screws that thread into the Al base plate, passing through the Al or plastic cover. I have seen ones that are screwed in from the bottom, but I _think_ those were 310s.

3 screws with rubber standoffs hold it to the car, any other screw heads will be for the cover, else, they are screwed in from the bottom. Some helpful PO may have glued it together, the sod.

On really early RBs the cover was held on by a spring passing over the cover, but I presume you would have figured that out yourself...

Andrew