Part III of my electric gremlins...........

Jorge022770 · Post by **Jorge022770** » Fri Jul 22, 2005 10:01 pm

Ok, battery is juiced up, contacts clean, grounds check as far as I know...alternator contacts all cleaned......start the engine without problems,..........and then I see the ammeter moving slowly to the (+) side. WHen it was almost all the way on the (+) end, I stopped the engine and disconnected the battery.

What is wrong with this baby??????

Jorge

TR · Post by TR » Fri Jul 22, 2005 10:13 pm

Voltage regulator (little box on firewall) stuck on charge. Take the cover off, it should flutter back and forth when the engine is running...

Jorge022770 · Post by **Jorge022770** » Sun Jul 24, 2005 12:11 am

TR:

First of all, thanks for your help. Now, there are two "things" in the volt. regulator......which one will I be looking at? And if its not moving like you say, is there a way for me to fix it?

Thanks again!

Jorge

TR · Post by TR » Sun Jul 24, 2005 12:37 am

It is easy to fix...

Get a big hammer, strike wildy, then buy a new one...

There should be a contact that looks like a set of points, they should flutter open and closed very rapidly with a good battery. You can also try adding a load like the headlights to see if that changes anything.

You can try cleaning, putting points grease on the pivots, etc. but typically when they go, they are gone...

I'm not sure about the compatibility of the 510 units, but they have replacement electronic ones that work great and are not expensive. TR

Jorge022770 · Post by **Jorge022770** » Mon Jul 25, 2005 10:57 pm

TR.....(all others welcomed to share their expertise!):

First I removed the volt. regulator's cover and started the engine. The thing that looks like points didn't move from it's original position. Then, I was reading the awfully translated Datsun manual, and it talks about the gaps on the volt. regulator...and about bending to adjust. I didn't want to mess things up more, so I did a very slight bend on one post....

When I started the engine, the thing that looks like points moved to the other contact point, but it didn't go back and forth like you told me. However, the ammeter is now in the middle again to how it normally is.

BUT, when I turn the headlights on, the ammeter moves about 1/3 of the distance towards the (--) side now! I checked grounds and they are fine. The engine revolutions are not affecting the intensity of the headlights, but when the revs go up, the ammeter starts moving back to the center.

Is this a sign of something???

Jorge

TR · Post by TR » Tue Jul 26, 2005 12:38 am

It sounds like the regulator is not working, but possibly something with the alternator, too.

In your first post, the car was overcharging (gaining more and more + as it ran) because the regulator was stuck closed.

Now the car is not charging enough (going negative under load), but still trying to charge (gaining back some charge at higher RPM).

I would guess from what you described that both parts have issues, but there is the chance that the regulator is not making a good contact on both circuits (possibly from bending, possibly just because it is old!) and now it is back in the overcharging mode but weak.

The one symptom that really points to the regulator is that it is not fluttering back and forth, but sticking on one side or the other. The only other reason the regulator wouldn't flutter would be if the alternator was not charging at all, but previously it was overcharging, so you know it has worked recently.

Maybe try tweaking the regulator arm again and see if you can get it to flutter. Otherwise it might be time to make your way to the autoparts store. Also, check to see if a 510 regulator is compatible, if so, I think I have some used ones in the garage...TR

Jorge022770 · Post by **Jorge022770** » Tue Jul 26, 2005 1:18 am

TR:

You must be tired of my questions by now...but you have been extremely helpful in this electric ordeal I am going through! I will try the tweaking again tomorrow (It's Monday night 11pm right now....I would do it, but I need plenty of illumination!). Now, are the "points-look-alike" on both sides of the volt. regulator supposed to flutter back and forth?

One side has a bigger gap specifications, but I noticed that it is connected to a wire that has no counterpart on the harness connector (harness has six slots but only 5 of them have wires).

Now, as to the 510 volt. regulator's compatibility with mine.....I don't know where to go to find out if indeed they are compatible! I noticed that the Datsun service manual that I have(the old one with yellow cover) shows different alternators and volt. regulators on the 1600 section and the 2000 section.....mine are actually the same as the ones in the 2000 section (although I have a 1600 engine!). If the 2000 and the 510 volt. regulators are compatible, then mine is as well.

Thanks again TR....and please

don't stop helping me!

Jorge

TR · Post by TR » Tue Jul 26, 2005 12:34 pm

A quick check with an auto parts store should give you the answer. If they list the same part number for each application, they are the same.

Regulators are built differently, so knowing exactly without looking at it is difficult.

Yes, the arm holding the points should flutter so that the points open and close rapidly...

There was a time when I needed help and people helped me with my first car, I'm returning the favor...

Good luck! TR

datsunrides · Post by **datsunrides** » Tue Jul 26, 2005 11:17 pm

Jorge,

FYI, I was able to purchase a new solid state voltage regulator a year ago from Autozone that was model specific. They actually had a listing for our Roadsters! Unfortunately, I can not find the receipt with the part # on it. I believe it cost something like $15. Stop messing with that old regulator and get it replaced. One less thing to have to troubleshoot.

Mark

Jorge022770 · Post by **Jorge022770** » Wed Jul 27, 2005 12:28 am

Mark:

I think i will take the advice that you and TR are giving me...it seems like a PO already messed with the thing anyways. I will look into the Autozone regulator...there's a store down the street here.
Thanks again for the help...I'll keep u posted

TR · Post by TR » Wed Jul 27, 2005 12:54 am

I think the last one I got was $35 or so. Get one that is only about 1" think instead of 2.5". The thinner one is the solid state model that does not use the parts that failed in the one you currently have. It will probably be hard to find one of the old style thick ones, anyways.

Post by **ppeters914** » Wed Jul 27, 2005 2:47 pm

...or just forget about the voltage regulator and do the GM alternator swap. Not as cheap up front as just replacing the regulator, but maybe cheaper in the long run.

Post by **spl310** » Wed Jul 27, 2005 4:45 pm

Cheaper in the long run?? I have torn apart several Roadsters and have owned a few drivers along the way. Almost all still had the OEM parts under the hood. 30 plus years of service is good enough for me to go back with stock! Now, if you are in need of more power, that is a different matter...

Post by **ppeters914** » Wed Jul 27, 2005 5:25 pm

Ha! If there was one person who was gonna mention that, it would be you, Sid....and you're absolutely right. However, I did say "maybe."

Considering that Jorge is in Datsun Roadster Mecca (aka SoCal), I'm sure another roadster owner has a spare regulator to swap in and see if that's the problem.

He can also just remove the alternator and regulator and take 'em down to the FLAPS to get 'em tested and confirm these are working/non-working parts. If both the regulator AND alternator need replacing, then maybe the GM alternator swap would be cost-effective.

67 1/2 1600 · Post by **67 1/2 1600** » Wed Jul 27, 2005 6:27 pm

I have a spare that works... I think?? I have what I beleive is a original regulator a Mitsubishi one just like the alt. I am pretty sure my spare works. PM me your address, and we can think of a day we can check out your car.

Joaquin