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voltage regulator adjustment hard

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M

mightymidget

Jedi Knight
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I checked my generator on my 68 Midget and it is throwing out plenty of juice through the method of crossing wires and watching voltage climb.

So I called Moss to order a new regulator, spade type with swing clamp on cover. the ones already adjusted are a back order item. with no date to receive.

So I am thinking of buying one that isn't adjusted and adjusting myself. Moss makes it sound complicated. Is it

"KIS" how do you adjust one?
 
British Victoria has one, aftermarket pre adjusted from the UK listed as Postive earth...my Midget is Negative earth.

Had not thought about this but does it make any differnce. Are they wired to the car the same?
 
Makes no difference, tis the generator that has to be sparked.

I have never had any luck adjusting regulators. Seems to be beyond my capabilities.
 
I think I am going to wait on the Moss, I call British Victoria today and they have no Tech dept. and the person on the other in of the line sounds like a overseas contract worker.

Today Moss told me it made no diffence also about the way car is grounded also. Moss also told me the wait shouldn't be to long that they are at the place that pre test and adjust them.
 
There is a Lucas "Cheat Sheet" someplace to explain the adjustments.

The first thing I'd suggest is rather than replace it, clean the contacts in the thing with some ScotchBrite (red) and try it again before any "adjusting". If the dynamo ("generator" in Yank Speak) is putting out and polarised, you're half-way home.

Think of the regulator as a simple set of relays... kicking in at a specific time (voltage) and adjustable with a VOM (analog is best, here).

I'll try to hunt up the "Cliff's Notes" version of the procedure, but think there's a section in the Bentley books to cover it as well.
 
I hope the "Cliff" notes will be found. I sure could use that info as well. I have been fighting a charging problem with my regulator on my 3000.

Charlie
 
I think the Moss catalog has instructions but theycan be found on the www easy enough. It's not too hard, especially on the BE as I don't think it has a current regulator so you can just use a simple volt meter. Like Doc said, analog is best since a digital may not be damped and will probably just jump around too much to be of any use.
 
See https://fromtheframeup.com/LucasTechnical.aspx, section 5. More than you ever wanted to know about Lucas control boxes.

There are several adjustments, but the only one you're likely to need is the pull-in voltage for the main regulator relay. This is described in the shop manual and in the Haynes manual. It's not too difficult to do.

I've done a full adjustment on the bench (i.e., out of the car) and it's not terribly difficult. But it does require a variable-voltage power supply and a decent voltmeter.

Of course, make sure that the contacts are clean and in good shape. They build up a lot of crud as they operate. Get all this off, and run some rough, brown paper between the contacts to polish them. If the contacts are significantly eroded, you might have to use fine emery paper, but try to avoid it if you can. Be sure that the battery is disconnected while you do this.
 
I've tryed to set one up with a couple of incorrect VOM meters and did'nt have much luck. So I worked my way up from the low end of the adjustment range and thought I had it right. Worked fine till I made a high speed run of several miles during which the gen let go. Set the mechanical adjustments (gaps) and nothing more without the right volt meters or it may cost you!
Bentley manuals and Lucas manuals cover the procedure quite well.

Kurt.
 
Well my $500 Midget is charging, I am getting up to 14.8 volts at the battery at RPM.

I received my new VR from Moss and this week-end decided to install. With all the information given to me, I had a nag in the back of my head about the generator needing to be polarized.

So before I installed the new voltage regulator I decided what the heck, won't hurt to polarize again if it has already been done. On the first spark I heard a click. Cranked it up super juice !

So I didn't need a VR after all. I guess this is good news. If I would have installed the VR with out polarizing and it did not work..............

This car has been a great teacher to me
 
mightymidget said:
This car has been a great teacher to me
Click to expand...
They all are. Tunebug has taught me all sorts of things about practical mechanics. Books and even y'all gurus are wonderful, but there's nothing like getting in there and doing it.
 
I am glad it went well for you, I have successfully rebuilt, fixed adjusted etc. pretty much every component you can think if on Sprites and other LBCs...except voltage regulators, every time I have tried it doesn't behave anything like the manuals say it should, nor can I coax them to. I have broken a couple but never fixed one :wall:
 
I have just been through the process of troubleshooting the regulator (control box) on my BT7 3000MK2. I looked at all of the available shop manual procedures all of which say you have to disconnect the A and A! wires from their terminals and jump them together before proceeding. I finally took the car to a shop that specializes in older cars and watched the expert adjust the screw that sets the voltage. He just removed the cover from the regulator and started adjusting the screw on the left while keeping an eye on the voltmeter until it settled down around 14-16 v at idle. Various sources say that an initial charging voltage of 16+ volts is too high but that's what the original specs call for and it seems to be very tricky to get the voltage any lower than 16V without having it too low to keep the battery charged. I think the only real risk is to the life of the battery but that isn't really a significant cost if everything else works.
 
Here is all I know about voltage regulators on a Bugeye
I had a 59 bugeye and my battery kept going dead and the mechanic I was using kept replacing the generator saying the stuff from India was no good.
Finally the mechanic had a young kid helping him one day and the kid said maybe it's the VR and the mechanic said no they are preset when you get them from MOSS. The Kid checked it anyway and it wasn't preset. He set it and no more problems.
 
jeffyfarley said:
I have just been through the process of troubleshooting the regulator (control box) on my BT7 3000MK2. I looked at all of the available shop manual procedures all of which say you have to disconnect the A and A! wires from their terminals and jump them together before proceeding. I finally took the car to a shop that specializes in older cars and watched the expert adjust the screw that sets the voltage. He just removed the cover from the regulator and started adjusting the screw on the left while keeping an eye on the voltmeter until it settled down around 14-16 v at idle. Various sources say that an initial charging voltage of 16+ volts is too high but that's what the original specs call for and it seems to be very tricky to get the voltage any lower than 16V without having it too low to keep the battery charged. I think the only real risk is to the life of the battery but that isn't really a significant cost if everything else works.
Click to expand...

Too high of an output can cook your generator as well. BTDT
Kurt
 
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