No Voltage Stabilizer on Late Series 3?

[jac04]

Nium-
Where did those resistance numbers come from? My brand new Genuine 560794 sender reads higher than that at room temp.

Anyhow, I hooked up a car battery to the system "as-is" with NO voltage stabilizer in the circuit. The fuel gage tracked perfectly with the sender position, and the water temp gauge read a little over "N" at 173 F.

Note that the water temp test was done with an old sending unit that showed less resistance at room temp than my new one (don't know why, they are the same part number). I will need to pull my new temp sender from the head and use it for my test. I expect this to produce a slightly lower gauge reading for the same temp. My thermostat is 179F, so I expect this to produce a reading in the middle of the "N" range.

So, things seem OK without the stabilizer with a constant 12 volts. Next, I may install the stabilizer and see what happens....or just put everything together and not worry about it.

[Nium]

Nium-
Where did those resistance numbers come from? My brand new Genuine 560794 sender reads higher than that at room temp.

I did a number of searches on the Land Rover UK Forums and a couple of different posts stated that was the resistance numbers people had measured. If you've got yours working then and don't worry about it.

[brucejohn]

If the stabilizer is a "regulator" wouldn't the purpose of having it in the system be to keep the meter readings consistent throughout the varying conditions of driving? While they may work without, I seem to remember a science class in high school where we studied the importance of both accuracy and consistency throughout our measurements?

Sorry, I am spouting off.

[jac04]

^^ Yes, true. I'm still wondering what is different about the late Lightweights that were not factory equipped with a voltage stabilizer. Are the gauges different? Is there something else that keeps the voltage to the gauges constant as the system voltage changes?

[jac04]

In case anyone is interested:
I tested the fuel gauge and water temp gauge again tonight with no voltage stabilizer. The gauge readings were not affected by any change in the supply voltage to the system. I first tested with a 12 volt battery hooked up with a supply voltage just over 12 volts. I then connected my battery charger to the battery and the result was a voltage of 14.5 to 14.7 volts. The gauges read the same no matter what voltage the system was supplied.
So, no voltage regulator for me (at least for now).

[kevkon]

As far as I know any Smiths non-mechanical gauge requires the stabilizer/ regulator. You might want to give Nisonger a call if you are thinking of running them without.

[Les Parker]

My understanding is that the stabilizer smothes out any spikes in the info sent by the transmitters, 12v in 10.2v out (consistently). Thus if you go round a corner,down a steep hill etc. the guages on the dash do not jump out all over the place, as the early IIa's did.

Just my 2p

[kevkon]

Les,that's what my understanding is as well. As I said, I believe that's why they termed the device a stabilizer. I'd still give Nisonger a call to see if any damage to the gauges can occur if the stabilizer is not used. We are talking Lucas electrics here, so anything is possible.

[jac04]

Remember, this vehicle did not have a voltage stabilizer to begin with. It's not that someone removed it - it never had one from the factory.
This corresponds to the info found by Nium at:

http://forum.landrovernet.com/showthread.php?t=163110&highlight=lightweight+voltage+stabilizer

Things seem to be OK so far without the stabilizer, and the fuel gauge responds fairly quickly, but it does not "jump around" if I quickly move the float on the sending unit.

Also, the stabilizer supplies the gauge circuit with a constant voltage. How does this 'smooth out' the variable resistance of the sending unit? It doesn't. It just gives the gauges a constant reference voltage.

My gauges are unaffected by any change in reference voltage, so why would I need a stabilizer?