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fuel guage

Posted: Tue Jul 05, 2005 12:11 pm
by richard.baker707
Can someone help me with my gauge not working I've supplied direct live to the back of the gauge and the needle moves past the full mark so I know its not the guage. what I have is one wire going to the voltage regulator and one all the way back to the fuel sender unit which I'm guessing is earth. how does the voltage regulator work and how many green wires should be going in and from where to which terminal B or I the wiring has been modified and there are a couple of spade connectors on green wires not attatched this could be the problem but I dont want to blow the regulator. all help appreciated.
thanks Rich

RE: fuel guage

Posted: Wed Jul 06, 2005 12:03 pm
by brixtonmorris
3 green wires, 1 carries power from the fuse box, the other 2 carry power to the oil pressure switch and the wiper motor. the fuel gauge terminal is just used as a junction for the wires. the other terminal on the fuel gauge sender, sends the power to the fuel tank unit. this wire going to the voltage regulator is it going to the v regulator or the voltage stabliser. the fuel gauge sholud be connected to the fuse box and not the voltage regulator, (the large black box on the bulkhead).
B & I sounds like the voltage stabliser on the back of the speedo.
3 green wires connected to 1 terminal a 1 green with blue (i think) going to the fuel sender unit.
try putting 12 volts in to the fuel gauge, using the body as the earth return, this check will ensure power is travelling through the sender.

Posted: Wed Jul 06, 2005 2:12 pm
by richard.baker707
ok thanks will see if i can work it out

Posted: Wed Jul 06, 2005 5:06 pm
by Alec
Hello Richard,
the fuel gauge runs off the voltage stabiliser located on the back of the speedometer. The actual gauge voltage is about 10volts, so putting a temporary 12v feed wil not give an accurate result. Wiring colours are green to the stabiliser and light green from the stabiliser to the instrument. The sender unit has a green\black wire connecting it to the instrument.
The simple check is to switch on the ignition and connect the green\black wire to a good earth point on the body and the gauge should then read full scale, i.e. full. (This also applies to electrical temperature gauges). If not try the rear of the instrument sender terminal to earth. If it still does not read then it is a supply or gauge fault, although the sender unit is the most likely culprit, usually due to poor earthing from the tank to body.

Alec

Posted: Wed Jul 06, 2005 9:01 pm
by richard.baker707
HOORAY FUEL GUAGE WORKS (BROKEN WIRE)
THANKS FOR THE HELP

Posted: Sun May 14, 2006 8:09 am
by lalaw
Hi,
I have a similar problem.
My Fuelguage shows almost full tank until it is almost empty.
I don't have any voltagestabiliser at the back of the instrument.
The has at some point ben converted to alternator and the voltageregulator on the bulkhead is disconnceted
Should I just a voltage stabilser?
My car is a -59.

gauge

Posted: Sun May 14, 2006 9:21 am
by Willie
LALAW Do you have a bronze faced speedometer or is it black?

Posted: Sun May 14, 2006 9:33 am
by lalaw
It is the bronzed face type
Br Lars

gauge

Posted: Wed May 17, 2006 9:38 am
by Willie
If you have a bronze faced speedo then the tank sender unit should have
a nut to secure the wire on the contact (feel under the boot shelf). If it is a nut then that is correct but you could have a faulty sender unit or faulty gauge.
Your car does not need a voltage stabilizer to work correctly.

Posted: Wed May 17, 2006 8:04 pm
by lalaw
OK, I will check.
I have noticed one more thin when fuelpump "tick" then the nedle will make a small jump.
Br Lars

jump

Posted: Thu May 18, 2006 4:22 pm
by Willie
That is because when the pump ticks it is using the battery and this is showing
on the highly sensitive 'bronze' type fuel gauge. It could be indicative of a bad
battery or poor connections though.

Posted: Sat Jun 03, 2006 3:00 pm
by ESAD757
Hi

I have a 1960 Moggy Saloon and my fuel guage does not work also,Please could someone tell me what wires should go where i have 3 going to the back of the gauge and one connecting to the sender unit in the boot, I have dismantled the sender and all seems ok,Does the fuel tank need an earth and if it does where is it,

How do i test that the guage works

Also i have a black with green thin stripe in the back of the speedo that is not connected to nothing

Thanks

Jason

no Gauge

Posted: Sat Jun 03, 2006 8:48 pm
by Willie
The Green/Black wire should go to one side of the fuel gauge( it is the feed
from the tank sender unit), the other side of the gauge should have three
Green wires on it. The tank is earthed via the fixing screws to the body.
Just to check, your 1960 car should have a Bronze faced speedo?

Posted: Sun Jun 04, 2006 3:24 pm
by ESAD757
Hi

I am still struggling i have tested the fuel guage float by shorting out the wire to the float onto a good earth,This should have caused the fuel gauge to register full.

I then connected a good earth from the speedo and then shorted out the 2 terminals on the back of the fuel gauge and this did not work.what has been happening intermittantly is that when the speedo is hanging down from the hole ,when the case touches the keys in the ignition the guage goes straight to full,then if i turn off the speedo light under the speedo the guage goes back off th zero ???

HELP

Jason

gauge

Posted: Sun Jun 04, 2006 8:57 pm
by Willie
Have you connected the green/black lead to the terminal on the gauge which
is marked 'T'? and does the terminal marked 'B' have three green wires on it
which read 12 volts with ignition on? Also,do you have a bronze faced speedo
and is the terminal on your tank sender unit secured with a nut i.e. not a push
on Lucar connector.

Posted: Mon Jun 05, 2006 12:08 am
by ESAD757
Hi

I have abronze faced speedo

Also have the float with the nut connection

I already have 3 wires connected on one terminal and 1 green on the other terminal.

Thanks

Jason

Fuel Gauge

Posted: Mon Jun 05, 2006 6:18 pm
by Willie
JASON, I may have found your problem. I have a spare Bronze faced speedo which is in perfect working order as far as I am aware. I have done some test on it and this is what resulted. On the Bronze type fuel gauges ONLY, applying 12v to the 'B' terminal and a full short to chassis on the 'T'
terminal you do NOT get a 'full' reading. The gauge merely goes from rest
position to 'empty' and the only time you get a 'full' reading is if you touch
the chassis lead to the casing of the speedo which I think is your finding?
This ties in with some earlier tests which I did which found that the 'nutted'
type tank sender unit reads 'high resistance' when FULL and low resistance,
(to Chassis) when EMPTY!! Not what you would expect! The Black faced speedos read exactly the opposite so,with these types, the sender reads low
resistance when 'full' which means that touching the sender lead to chassis
gives a 'full reading.

Posted: Mon Jun 05, 2006 10:20 pm
by ESAD757
Hi Willie and thanks for the reply

I still can't get the fuel gauge to work,I live in Twickenham middx is anyone nearby

,perhaps i could pop around and someone could solve my dilemma

Thanks

Jason

gauge

Posted: Mon Jun 05, 2006 10:32 pm
by Willie
Well, with the speedo out of the dash,which is the condition I am describing,
you say you had full scale deflection when the speedo case touched the
ignition key so the gauge is capable of reading full scale. when you short the
'T' terminal lead(green/black) to chassis does the gauge not move from rest
position to 'empty'?(with iginition ON of course)!

Posted: Thu Jun 08, 2006 9:37 am
by ESAD757
Hi

The gauge does not move at all ??

Any idea's

Jason