voltage regulator

[sp53]

When I started my tr3 yesterday, the generator light stayed on and the amp meter oscillated/went from charge to no charge, and I shut it off after a couple of minutes. When I open the hood, I heard a click sound like the regulator points had let go. So I started it back up and the light was off, but the amp meter was still kinda freaking out. Then after maybe a couple of minutes, everything went back to normal. So before I went to work this morning, I took a piece of fine emery paper and gently cleaned the floating contacts in the regulator. In all my years of driving tr3’s, I have never done that before. Please tell me that everything is going to be alright.

 

[Geo Hahn]

Okay... "everything is going to be alright".

Actually my control box was acting up -- in my case the points sticking and the light coming on and staying on after the engine was shut down. Cleaned it up a bit and adjusted it a teensy bit and the problem has not recurred.

 

[NickMorgan]

I am sure it should be OK. Possibly the output from the dynamo is a bit low. You should really have used a bit of card to clean up the contacts. I suspect that it was just the car's way of telling you that it is not getting out enough!

 

[Stig]

Mine's internal.

 

[sp53]

Right on Geo I appreciate it. I figured the problem was probably the regulator, but I needed to hear that they sometimes stick and can be repaired. The regulator is one thing that I never tinkered with because I figured I could do more damage than good. I think I remember a time with these things that you actually had to purchase a generator and a regulator together or they would not be under warranty. What I did was just keep everything and not turn in the core because I was never sure what one went bad or if one of the units caused the other to go bad,heck I still have extra stuff. I understand the brushes and armature concept and could test those, but I was never sure about the voltage output and what effect that would have on everything.

 

[sp53]

Thanks again Nick and Stig. I guess I am just old fashion and a purist when generating enough. Nick did you mean just use a piece of paper in order to cut down on taking metal off? I was kinda of uncertain about that and the dyno is perhaps a year old.

 

[martx-5]

Hey Stig,

I see that your Delco 10SI alternator is set at the "3 o'clock" postion. I had mine set at that before I put the engine and trans in the car, and wound up moving it to the 12 o'clock position, as the plug-in for the regulator wires weren't right up against the fender well. Mines going in a TR3. I don't know if there is more room in a TR4 (or is this going in a TR3?), but I didn't have any other issues with the engine etc. by clocking it to twelve.

Edit: pic at the 12 o'oclock position in the car. I had the exhaust header on there earlier, and there was plenty of room.

 

[NickMorgan]

I think the issue with using something abrasive is that you can roughen the surface of the contacts, which will reduce the surface in contact and result in them burning our more readily. In reality it probably doesn't make that much difference.

 

[Stig]

martx-5

It looks tight, but there is plenty of room.

 

[TR3driver]

but I was never sure about the voltage output and what effect that would have on everything.

Two things can happen with too much output from the generator :
1) Too much current will overheat and destroy the generator itself. It won't put out enough current to hurt anything but itself. If you ever see more than 20 amps of charge (less with headlights on) for more than a few seconds, you should probably disconnect the field circuit until the problem can be found (drive home on the battery). And anytime the generator is replaced, you should double check the VR settings. Even new units are sometimes not set right, so I'd also check a new unit.

2) Too much voltage will boil the electrolyte out of the battery. The acid splash causes corrosion around the battery; and the loss of electrolyte will eventually ruin the battery. If the battery gets bad enough (essentially an open circuit), then the voltage might go high enough to cause problems to other devices. But that is unlikely, IMO.

Something else to check is the ground connection between the battery and the body, and the engine and the frame. The body connection in particular is prone to getting painted as part of a restoration, and paint doesn't conduct well at all. Either scrape a bare spot under the cable end, or put a new "external star" type lockwasher in the joint. The points of the star will cut through the paint.

If originality is not an issue, an even better solution IMO is to add a heavy ground cable between the body ground point and the engine.

 

[sp53]

Hi Randal and thanks for your note. I stated up my tr3 and drove it for awhile and when I shut it off the generator light stayed on evidently like Geo’s. I open the cover and separated the points and it temporally fixed the problem, but the problem came back. I thought about something that Nick suggested in that the system might not be getting enough current/voltage, so I unhooked the generator and replaced the spade fittings. Perhaps the lager spade fitting had a bad connection and was giving an intermittent signal. I fixed that and now the problem appears to be fixed. However, I still do not trust it for an open road tour. I do have a NOS regulator that I could put on, but I am afraid of damaging that. So my question is can a generator hurt a regulator if the generator appears fine? Can a generator put out too much current or voltage? Or do they just put out a set voltage and the current is minimal. I was thinking about your 2 suggestion and perhaps I have too voltage coming out of the generator or the voltage is not regulated or something because the battery does show a little moister on the top of the battery. The battery is a Sears golden and I checked the liquid and it appears fine and the battery does hold a charge.

 

[TR3driver]

I won't say it's impossible for a generator to harm the regulator, but I've never seen it happen. IMO you're safe putting on your NOS regulator.

HOWEVER, at this point there are very few true NOS components around. There are, however, lots of components that someone found to be defective way back when and put back on the shelf; which are now being sold as NOS. Plus of course, some components were bad right from the factory. Bottom line, just because it's "NOS" doesn't mean it works right.

Perhaps I don't understand your question about too much voltage or current ... my post above outlines both cases and the bad effects of each. Neither one is likely to harm the regulator (tho too much current will definitely harm the generator).

However, the stock TR3 charging system is rather primitive ... slight overcharging is normal with the headlights off (and slight undercharging with them on). This is a side effect of Triumph choosing a 2-bobbin regulator instead of a 3-bobbin. That's also why the voltage set point given in the manual (15.6 - 16.2) is so high, because it drops with generator output current. In effect, the 2-bobbin regulator controls (reacts to) the sum of current and voltage all the time.

 

[TR3driver]

Sure hope Basil gets the server's hiccups solved soon !

 

[sp53]

Hi Randal and I hear you about the NOS stuff and perhaps I should try this NOS regulator now while everything is working because I purchased it on eBay a couple of years ago. The regulator that is on there now has been on there for about 12 years and do you think that is a long time. I might have fixed the problem by improving the connection on the Generator though. Anyways I guess my concern on suggestion 2 was answered when you demonstrated that 15 to 16 volts is permitted back into the battery or did I understand that wrong. So they can operate normal and still over charge because of the primitive factor.

 

[TR3driver]

What happens is that, as the generator tries to drive battery voltage over about 14.4, the battery keeps taking current. This, plus the current required to operate the ignition (radio, OD), keeps the regulated voltage below the "open circuit" value given in the manual.

The few amps into a fully charged battery doesn't harm it directly. But it does slowly 'boil' away the electrolyte, which will eventually kill a "no maintenance" battery (where you cannot add water). And although the fumes mostly blow away harmlessly, they do tend to promote corrosion in the area.

But most people with "original" cars don't put enough freeway hours on them to have a problem with overcharging. Around town it's much less of a problem because of the extra loads of brake lights, turn signals, etc. and lower output from lower engine rpm. So my advice is Don't worry, Be happy.

That said, this is all ancient history for me; since I decided over 30 years ago that the stock generator just didn't cut it on a daily driver (especially commuting to work in the snow) and converted to an alternator.

 

[TruCraft]

I read this post and others, then had an electrical friend(Jim)come over to look at my TR3.
<span style="text-decoration: underline">Things he noticed</span>:
*Red light on dash is on.
*Gauge shows 0 even after starting.
*Gauge shows -3 with park lights on.
*Battery shows 12.5 volts with car off.
*Battery shows 12.5 with car running at 2,000rpm.
He checked everything and said regulator is messed up!
We pulled the control box cover and checked the coils and contacts.
Looking at the firewall the left side contacts were badly corroded. Loosened the lock nut and removed the screw. Sanded it with 600# paper and the other side. Set gap to (.015)and tightened the lock nut.
Now we are charging!
The red light is out on the dash.
The gauge shows a positive 10-12 after starting and slowly returns to about +3.
With all lights on, the gauge still shows +1.
Took a night drive and everything was great, except for the headlights pointing at weird angles!
The gauge shows the battery is being charged, and for the short trips that I take this will be good.
After retuning home tonight the battery voltage checked 12.8
Lyle

 

[TR3driver]

I hope it holds up for you, Lyle.

Normally, you should use a "contact burnishing tool" on the points, rather than sandpaper. Supposedly the sandpaper leaves too rough a finish, which will rapidly burn again in operation. Was a standard service tool "back in the day", but I don't know if they are still readily available.
https://www.tessco.com/products/displayProductInfo.do?sku=93802&eventPage=1

 

[Don Elliott]

I always figured that if you left a grain of emery or sand from the paper in the surface of the contact . . . well sand is not a very good conductor.

Randall - I think my regulator is set at 13. 6 volts because I still run with an original type Lucas generator. When it was at 14 - 15 amps (for the first 80,250 miles that I had the car) the electrolyte used to boil out all the time and ruined my battery box all around and under.

In 1990, I re-set it to a lower setting as in the manuals, and it has never boiled in 18 summers of hot weather driving a little more than 100,000 miles and I never had to re-adjust it again. While everyone buys and installed one of those plastic battery box liners to avoid this, I have not needed one in my TR3A becuae it doesn't boil out. I'm on my third battery with the LUCAS on it and got 5 years from each of the first two batteries and now have over 6 years on the one shown here.

 

[TR3driver]

In 1990, I re-set it to a lower setting as in the manuals,

As in what manuals, Don? Here are snippets from the Bentley, and "Lucas Generator and Control Box Tests".

BTW, TS13571L has no plastic liner, and the original generator acts just like I remember. Very slight charge into a fully charged battery with no devices on; and a slight discharge when running with headlights. If I had a heater, I might tweak it up just a bit.