Fuel/temp gauge wiring

[SRQJeff]

Finishing up a new wiring harness on my SV. It shows that the fuel and temperature gauges connect to the little voltage regulator under the dash. Can anyone tell me (a) if the regulator is polarized, i.e., does it make a difference which set of terminals you use, and (b) likewise, does it matter which terminal on the gauges you connect it to? Like, does the fuel gauge care which terminal talks to the sending unit?

Thanks.

 

[Tom H]

Can anyone tell me (a) if the regulator is polarized, i.e., does it make a difference which set of terminals you use,

No, not polarized, UNLESS you are using an aftermarket solid state version

and (b) likewise, does it matter which terminal on the gauges you connect it to? Like, does the fuel gauge care which terminal talks to the sending unit?

Again , no, doesn't matter, EVEN IF you use a solid state version of the regulator

Tom

 

[SRQJeff]

Fantastic. Thanks.

I'm installing the Pete's Performance harness. I should have it done today except for a few cosmetic touches. In case anyone else is considering it, I'll have about 25--30 hours in the job by the time it's done, assuming I don't have a lot of troubleshooting to do after I put the battery back in. It could have been worse. My only advice is to find a cheap source of slide terminals before you get started. A buddy has a drawer full of them in his garage, so I didn't have to buy any. Advance Auto wants $5 for a package of seven of them, and they aren't even the kind with built-in shrink wrap! You can get a bag of 100 for about $6 on Amazon.

 

[Dzynr_Ron]

I'm in middle of Petes kit too, many hours getting interior/dash apart. So decided while it was out to completely disassemble & strip vinyl facing off and paint gloss white ! Guages should pop now But curious about this regulator,
there is a small component with (fried) green wires to it, its spade bits are loose, do I need to find a replacement for it ? Modern part suggestions ?
thx,
Ron

 

[mikephillips]

What the regulator does for the fuel and temp gauges is smooth out the incoming voltage so that the needls have less tendency to move around. So if your current one is broken you do want to replace it. I personally have had mixed results with original style replacements, quality control apparently not being what it should. But since it's not something unique to Sunbeams other vendors like Moss Motors carry solid state versions if you want to try them. But remember, solid state is polarity sensitive so be sure to get the one for use with whichever ground you're using.

 

[SRQJeff]

wiring

I'm in middle of Petes kit too, many hours getting interior/dash apart. So decided while it was out to completely disassemble & strip vinyl facing off and paint gloss white ! Guages should pop now But curious about this regulator,
there is a small component with (fried) green wires to it, its spade bits are loose, do I need to find a replacement for it ? Modern part suggestions ?
thx,
Ron

Yeah, like Mike says.

I hooked up the battery a couple days ago. Everything seems to be OK except that the high beam stays on with the switch in either position, and (this is the tough one) the starter engages with the key switch in the "on" position as well as "start." Switch and solenoid check out OK, and the switch is hooked up right. Still scratching my head.

 

[Paul A]

Yeah, like Mike says.

I hooked up the battery a couple days ago. Everything seems to be OK except that the high beam stays on with the switch in either position, and (this is the tough one) the starter engages with the key switch in the "on" position as well as "start." Switch and solenoid check out OK, and the switch is hooked up right. Still scratching my head.

Been working with Jeff on the starter issue. Sent him info and procedure for checking out the switch. If the switch is good then the next likely culprit is the solenoid. If the cables are correctly installed - that is, not reversed - then it may be the plunger in the solenoid switch is hanging up.

regarding the high beam challenge - check for correct wiring at the floor dimmer switch. As you face the floor dimmer in its mounted position the headlight dimmer power wure - 14 gauge blue wire - should be connected to the terminal on the right. Both hi beam and low beam wires are connected to the terminals on your left. Pete

 

[SRQJeff]

Now that you mention it, I don't even have the dimmer switch connected. The plug is just hanging there. Maybe that's the problem. But it seems like the lights shouldn't work at all that way. Hmmm...

 

[DanR]

Paul,

SRQJeff asked a question about Fuel/temp gauge wiring that dealt with the little voltage regulator under the dash.

His question was answered but I have one! How is this little regular powered?

Does the Gauge Power wire (18 Ga Red) connect to it?

As a reference: Rootes Manual WSM.145 Section N Electrical Equipment Page 55
shows it being connected also to a "Flasher Unit and a Fuse Unit.

I can not find this reference to it in your paperwork I received.

Sorry, that I am asking this but I am not having much success.

I lost your phone number but mine is 864-554-0814 or E-mail.

Thanks,

 

[mattinoz]

Dan, as I see it there are only 2 terminals on the regulator ( 3 in reality when you consider the ground connection through the can mount) they are not marked for polarity so assume there isn't a wrong way to connect it up. There is a green 12+ from the fuse block which then continues onto the flasher unit. Earthing is via the can mount, so make sure this a properly connected. The other wires which seem to be green/brown i think ( i'm reading from the wiring diagram) go to the temp and fuel gauges.

BTW I built a solid state replacement which fits into the original can so it looks stock.

 

[DanR]

Mattinoz,

Quote: Dan, as I see it there are only 2 terminals on the regulator ( 3 in reality when you consider the ground connection through the can mount) they are not marked for polarity so assume there isn't a wrong way to connect it up. There is a green 12+ from the fuse block which then continues onto the flasher unit. Earthing is via the can mount, so make sure this a properly connected. The other wires which seem to be green/brown i think ( i'm reading from the wiring diagram) go to the temp and fuel gauges. Un Quote:

You are correct when looking at the wiring diagram because it only shows two dots. But if you see the "regulator" it does have four connectors.

I am cheating a bit because I have two of my cars side-by-side in the garage. A Late '65 SIV that I am utilizing as the example to look at (+ the wiring Diagram) and my '67 SV that I am re-wiring using Paul's Kit.

The wires are Green and Black in the Diagram (and the original harness). My problem is the New Harness, determining what wire goes to where.... I either did not receive the layout for the fuse box or most likely lost it.

I'm sure Paul will get me straight again

I'm sure not smart enough to build let-lone understand a solid state system... as you have.

 

[mattinoz]

You are correct when looking at the wiring diagram because it only shows two dots. But if you see the "regulator" it does have four connectors.

DanR, yes there are 4 connectors but only 2 terminals. Each terminal is a pair of spade connectors, so my original suggestion is correct.

As to your particular dilemma, as you need a 12+ supply from the fuse block that should be easy enough to identify in your new wiring harness. This connects to 1 pair of terminals and the original wires from each of the gauges to the other pair of connectors.

If you have a multimeter you can test it before connecting the gauges, once you connect up the 12+ supply and properly ground the can, you should read 10 volts on the other terminal.

Oh and just be sure the connections on the gauges are correct, there is a right and wrong way to connect the senders in each case. It won't cause any harm if connected the wrong way round, the gauges just won't work, so swap the wires at guages if they fail to read. The fuel gauge is the one to work with assuming there is fuel in the tanks.

 

[Paul A]

Doug. Sent you an email.

For any others following this thread, in my kit the gauge voltage regulator is powered by a red wire labeled "Gauge Power" that comes off the main fuse box.
It is connected to the "B" terminal on the regulator. The gauges are connected to the "I" terminals on the regulator. If the regulator is working correctly there will be 10V going out to the gauges. Pete

 

[DanR]

Thanks, Paul!
When I could not determine where the Gauge power wire was to connect I starting comparing two vehicles. That is when I started asking questions. I just did not follow your instructions very well.

When they said "It is connected to the "B" terminal on the regulator" It did not sink in because I did not think I had a regulator.

From the beginning I have said that I was a Dummy when it came to electrical wiring.

 

[Tom H]

Dan,

Looks likle Paul has set you straight regading the wiring to the regulator. But there are a couple other things you may need to understand as you go forward.

If the regulator is an original type, and not a solid-state replacement type , the output will NOT read 10 V on any multimeter. Intead it is Battery voltage (nominal 12.6 V) but going on/off about 2 times per second. The average voltage of the on/off is 10 V, but because of the On/off 2 times per second it is virtually impossible to read the average. On a digital multimeter you will just see what looks like random numbers jumping around. If you measure a steady 12 V, the regulator is stuck ON. If you read 0 V, the regulator is stuck OFF,or something is not connected. Be sure the regulator case is grounded. If you measure a steady 10 V, then you have a solid-state replacement regulator. If you don't have a multimeter, you can test these voltages with a 12 V test lamp. If the regulator is working correctly you will clearly see the test lamp blinking On/OFF. And if it stuck ON, you can see that the light is same brightness, whether you test the B terminal or the "I" terminal. If it's a solid state reguulator you will see a steady, slightly lower brightness when testing the"I" terminal.

Regarding the connections to the gauges, mattinoz is incorrect. It will not matter which terminal you connect to on the gauge. Most common gauges ARE polarity dependent, but the SIII thru SV gauges are not. They operate by means a small heater inside that heats a bi-metal strip that moves the needle in proportion to the current thru the heating element. And heating element is not polarity dependent. It's because it uses this "slow reacting" heater element that the needle reads pretty steady even as the regulator puts out an ON / OFF 12 v.

Hope this helps,

Tom

 

[mattinoz]

Regarding the connections to the gauges, mattinoz is incorrect. It will not matter which terminal you connect to on the gauge.

I stand corrected, thanks Tom. My assumption re polarity came from experience with SV guages where it seemed i only got a reading when the wiring was the right way round. I'll be sure to test this when I get stuck into the next dash reco which is coming up soon.

 

[Tom H]

Matt, there are still other ways to mis-wire the gauge / sender set up. But once you have the two correct wires that go to the gauge you can connect them to either post on the gauge - of course only one wire to each post

From the original wiring diagram you can see that both wires to the Petrol Gauge are the same Grn/Blk color.

Tom

 

[Stephen]

If you rebuilt it did you use a resistor and if so what size resistor did you use

 

[Tom H]

Stephen, I assume you are asking Mattinoz about rebuilding his gauge regulator. If so, note that he said he built it with a solid state regulator, meaning it is a transistor circuit , not just a resistor. There are soldid state regulators available from Moss and, I think Sunbeam Specialties that are solid state and look like the original.

Tom

 

[Stephen]

gauge still hunting

Thanks Tom;
I missed that in SS $37 not to bad if its the problem
Looks like my temp gauge works I just got a fuse for my digital multimeter more accurate to read 10v so under the dash I go.
I am still trouble shooting mine. Seem fine for a while then it goes slowly down and up.
My car has someother type of Voltage regulator in there in a tube
I am starting to wonder if my sending unit is good
Stephen