41 replies to this topic

[rom44]

Well there are some other less intrusive things you could try before making the external voltage stabilizer conversion.  
 
First, try a mechanical inspection.  Shine a flashlight in the tank to see if the float is floating.  If it is not, you know there is a mechanical issue to sort out (binding arm, perforated float, etc).  
 
If the float appears to be floating, add some resistors to your Maplin order.  Buy a small quantity of 5%, 1/2 Watt resistors rated at 33 Ohms, 130 Ohms, and 240 Ohms (or close to these values).  These will be used to simulate the sending unit.  Disconnect the two wires at the sending unit.  With the ignition switch in the run position, insert the 240 Ohm resistor in the two wire terminals making sure the resistor leads are making good contact with the terminals.  The gauge should read close to empty but the needle should be up off its bottom position.  Replace the 240 Ohm resistor with a 130 Watt resistor.  After a few moments the fuel gauge should go somewhere near 1/2.  Finally try the 33 Ohm resistor.  The tank should read close to full but not be pegged all the way to the top.  If you don't get the empty-1/2-full results with these tests, repeat the tests by inserting the resistors in the green/black sending unit wire terminal and connecting the other resistor lead to a wire that you run directly to the battery (-) terminal.  If you get the correct empty-1/2-full results connected directly to the battery terminal, the black sending unit wire has an earth problem.  If neither test method makes the fuel gauge read correctly then you have cause to try the external voltage stabilizer conversion.

Sorry to answer after 5 years, but I also have issue with my fuel gauge. I replaced the sender by 4 different resistors:
- 270 and 240 ohms: gauge doesn't move
- 131 ohms: gauge on the red line
- 31 ohms: 3/4 full

When I connect directly sender wires together, gauge is higher than full.

I never seen the temperature gauge at "N", always below, so I think voltage out of the voltage stabiliser is too low.
What do you think?

[rom44]

News: I installed a 10V electronic voltage regulator instead and now the fuel gauge is OK. But temperature indicator indicates too high. It is between normal and high with engine at normal temperature...

[rom44]

Hello,

Any idea why the water temperature is higher than normal with the electronic voltage regulator?

[Spider]

Hello,

Any idea why the water temperature is higher than normal with the electronic voltage regulator?

 

I'd suggest checking the voltage at the Regulator that it is 10 Volts.

 

If that's right, then I'd say your old Regulator was putting out less than 10 Volts (and that's not unusual).

[rom44]

 

Hello,

Any idea why the water temperature is higher than normal with the electronic voltage regulator?

 

I'd suggest checking the voltage at the Regulator that it is 10 Volts.

 

If that's right, then I'd say your old Regulator was putting out less than 10 Volts (and that's not unusual).

 

 

OK, I'll check it.

How can I easily check if the temperature on the gauge is right? Is there a Temp/resistance curve available for the sensor?

Edited by rom44, 30 June 2019 - 07:45 PM.

[rom44]

I measured 9,93V between sensor and body, so voltage is OK.

Edited by rom44, 01 July 2019 - 08:53 PM.

[Spider]

 

 

Hello,

Any idea why the water temperature is higher than normal with the electronic voltage regulator?

 

I'd suggest checking the voltage at the Regulator that it is 10 Volts.

 

If that's right, then I'd say your old Regulator was putting out less than 10 Volts (and that's not unusual).

 

 

OK, I'll check it.

How can I easily check if the temperature on the gauge is right? Is there a Temp/resistance curve available for the sensor?

 

 

Search is your friend;-

 

http://www.theminifo...p-sender-specs/

[rom44]

Thanks !
I used a resistance of 90 Ohms which should correspond to about 90°C and gauge shows just higher than N. So gauge is almost OK.
2 solutions: it is really hot or sender is defective.
I will receive an infrared thermometer on Saturday to know the answer.

[Spider]

,,,,,,,,,,or sender is defective.
I will receive an infrared thermometer on Saturday to know the answer.

 

I've found all the new senders do cause the gauge to read Hotter than things really are.

[rom44]

,,,,,,,,,,or sender is defective.
I will receive an infrared thermometer on Saturday to know the answer.

I've found all the new senders do cause the gauge to read Hotter than things really are.

I don't know if it's original sender or if it was already changed.
New test today with 100 ohms resistor (should be 88°C), exactly on the N.

[Spider]

It really does look to be the Sender that's the issue then.

[rom44]

I installed a new sensor and I still read too hot.
I wired the original sensor and put it in water at 80°C. Needle was just in between normal and red hot. As voltage is good (9,97V measured between sender wire and ground), I think the issue is the temperature indicator.

Fuel sender works very well.

Is there a way to calibrate it? Add resistor, diode, move wires arround the lamella...

Edited by rom44, 31 August 2019 - 02:57 PM.