Voltage Stabilizer Question

[Mickey Richaud]

OK - Haven't seen this one posted.

Finally got the B on the road to have an exhaust system fitted and check things out. The temperature gauge, after just a few minutes, is just about pegged. After letting things cool off a bit, I took the radiator cap off and let it run a while. The gauge ran back up, and I put a thermometer in the open radiator. Coolant is flowing (slowly, it seems), and the thermometer never got above 160, even though the gauge is nearly pegged (needle just touches the hash mark by the "H". I have a spare gauge, and hooked it up (near the sending unit, and using one of the white wires of the fuse box for the other terminal) - it read the same.

I checked the terminals on the voltage stabilizer, and they both read a steady 13 volts. The fuel gauge seems OK, though I'm not sure.

I read somewhere that the voltage stabilizer output should be around 10 volts, and I have the website that describes a more reliable alternative, which I can build. Anyone have any experience with these doodads?

Mickey

 

[Keoke]

Voltage stabilizer out puts are about ten volts as stated.Your test using the spare guage seems to confirm that the stabilizer is defective.---Fwiw---Keoke

 

[Mickey Richaud]

Looks like I may have answered my own question...

I've ordered the pieces to make a new one - enough to make several, actually. Will let you know if it works out.

Mickey

 

[Bruce74B]

When you say voltage stabilizer, what do you mean? Is this the same as the regulator on the Alternator or something else? Is this why my fuel guage reads low and I suspect my temp guage may be readng low too???

Got me wondering now... /ubbthreads/images/graemlins/confused.gif

Bruce

 

[Mickey Richaud]

Bruce -

Check this article out:

https://www.mgcars.org.uk/electrical/stabilizer.html

Lots of good info on his pages.

Mickey

 

[Bruce74B]

Thanks Mickey!

I learned something new here...one great thing about this forum. I will have to check that out as my gauges are a little wacky...reading lower though.

Bruce

 

[Guest]

I would be interested to see what kind of circuit they use to replace the VR unit. It should be as simple and a droping resistor and a 10 volt zener diode to ground or a solid state regulator that is built like a transistor with three legs. A circuit can be devised to change the output voltage to whatever you want around that output rating as long as it would take the current the circuit is going to draw.
Bob

 

[Guest]

Oops, I didn't read far enough on the web site you furnished. Yes, that is what I was talking about for the solid state device that looks like a transistor. This would get you there without any experimentation.
Bob

 

[dklawson]

In addition to the site above, you can pick up a copy of the document I wrote up on the stabilizer:
https://home.mindspring.com/~purlawson/files/

The easiest/cheapest replacement (for negative ground cars)is to order a fixed u7810 (+10v) solid-state regulator from www.mouser.com (at under $0.70 /each) and mount that on the back of the dash. You can solder leads directly to that chip and hook up your gauges to those leads. It will supply up to 1.5 Amps so you're OK with the standard number of Smiths instruments. (I'll be adding that simplified instruction to my document in the future).

There is also a guy on eBay who routinely sells the Zener diode 10v sources you mentioned. I forget how much he gets for them.

 

[Mickey Richaud]

Thanks for the info, Doug. That's about the same price I paid for the ones I ordered. Amazing how flimsy the original stabilizer is. Glad to have found a solid state replacement.

Mickey

 

[sparkydave]

Mine gave up the ghost not long ago, and I went with the solid state replacement. Incidentally, a working voltage stabilizer does not put out a steady 10 volts, but a pulsed voltage equal to the battery voltage that turns on and off a few times a second. Now if my gas tank sender actually worked that conversion might be worthwhile!
-Dave

 

[Mickey Richaud]

Got the voltage regulator in and wired it up. Haven't checked voltage output yet, but the temp gauge stayed just below the "N" for several minutes after warmup.

Now the fuel gauge is reading low - at least I think it is, as I recently filled the tank, and the gauge shows a little less than half full. Have to see just how much gas is in the tank.

Aren't these cars great fun??? /ubbthreads/images/graemlins/crazyeyes.gif

Mickey

 

[dklawson]

You can test the fuel gauge by shorting out the (green/black?) wire on the sending unit to ground with the ignition turned on. This should make the gauge show "full". If this works, but the gauge doesn't show "full" when you know the tank to be "full", it means that you have a problem internal to the sending unit or it's float.

 

[Mickey Richaud]

Thanks, Doug - That's also on my list to check. The sending unit assembly is new, so my assumption (always dangerous!) is that it's OK.

Mickey

 

[Bruce74B]

[ QUOTE ]
Thanks, Doug - That's also on my list to check. The sending unit assembly is new, so my assumption (always dangerous!) is that it's OK.

Mickey

[/ QUOTE ]

I fugured the same thing, as I replaced my tank and sending unit two years ago. Last weekend,I tested the sending unit and found out it is shot already...another quality part from Moss /ubbthreads/images/graemlins/frown.gif

Bruce /ubbthreads/images/graemlins/driving.gif