FJ40 Fuel Gauge

[MidLife1977]

My fuel gauge suddenly stopped working yesterday on my 1977. All of the other gauges work fine. A few months ago I adjusted the fuel sender because it dropped the gauge more quickly than it should have (showing a 1/4 tank when I had 1/2 tank). After the adjustment it worked fine, then a few weeks ago the gauge stopped going all the way to "full" during a fill-up, but otherwise behaved normally. Now the fuel gauge is just not responding at all.

Has anyone else experienced this problem? Does this sound like a sender issue or gauge issue? Do I understand correctly that if the fuel gauge were faulty, it is likely the temp gauge would be as well? Figured I'd ask our forum of experts before ordering parts.

 

[rkymtnflyfisher]

Do you have a digital multimeter? Check resistance values to verify the sender and wiring is correct.

I'm unsure of what the resistance should be with that sender, check the FSM.

 

[Bloomer]

@MidLife1977 Did you ever find the issue and sort out the fuel gauge? Mine did exactly this yesterday. Worked fine one minute showing plenty of fuel, looked again and showed empty.

 

[MidLife1977]

I replaced the fuel float/sender altogether and had no problems since!

 

[Bloomer]

I replaced the fuel float/sender altogether and had no problems since!

Any recommendations on where to purchase? If OEM is available, do you by chance have the part number?

 

[bikersmurf]

Any recommendations on where to purchase? If OEM is available, do you by chance have the part number?

Sorry I’ve got no P/N.

They’re not all the same. Month and year of production? Month often doesn’t matter, unless it’s a changeover rear.

 

[Braden620]

I got one recently from city racer.

 

[Bloomer]

Sorry I’ve got no P/N.

They’re not all the same. Month and year of production? Month often doesn’t matter, unless it’s a changeover rear.

Sounds good. Thanks!

I did some searching and found a couple part numbers. What I found is:

83320-35020 1966 through 1972
83320-60050 1973 through 1978
83320-60051 1979 and later.

 

[TeamJB]

I have NOS 40 series gauges if interested you can message me.

 

[Downey]

Sounds good. Thanks!

I did some searching and found a couple part numbers. What I found is:

83320-35020 1966 through 1972
83320-60050 1973 through 1978
83320-60051 1979 and later.

35020 is 100 ohms empty, 3 ohms full, but with a 7 volt drop
60050 is 120 ohms empty, 17 ohms full, full 12 volts.
60051 ???, probably same as 60050

 

[Fandrover]

Rather than start a new thread I thought I'd jump on this as it seems finished with.

Tried faqs, search, etc...
Any resident experts or bodgers like myself suggest an order to check things and how with similar problem?
Nothing new, changed, restored etc but fuel gauge 2 months just showed empty one start up and needle hasn't moved since.
Fuel full (diesel)
No other gauges faulty.

So I'm thinking gauge/wires/sender/float/fairies/leprechauns?
No idea which most likely and therefore what to start checking first

Thanks as always

 

[Fandrover]

Sooooo about that gas tank sender haha.....

 

[Fandrover]

There are a lot of unconnected items here, any help identifying welcome...
White with black stripe wire - cut
Yellow with red stripe wire - cut
Both bound together going under fuel tank

 

[Fandrover]

Several tank feeder pipes into a junction with an pipe leading to what looks like a fuel filter then to nothing...

 

[Fandrover]

Will search for the above later but any quick info welcome

 

[GA Architect]

The plastic piece where the three line from the fuel tank goes into is the fuel vapor separator. The vapors then go out the top, to the check valve (filter looing object), then on to the charcoal canister.

 

[Fandrover]

Thanks for that

So I need to search for a charcoal cannister as my pipe goes to nothing after the check valve.

 

[middlecalf]

B/W ground wire for sender
Y/R sender wire goes to fuel gauge

 

[Fandrover]

Thanks for that..... Although totally confused now

As you can see my sender has 1 wire attached that goes to a ring connector attached to the seat mounting bolt.

The 2 wires you mention are not attached to anything

 

[Fandrover]

Even more confused now as I was sure the fuel gauge used to work but I don't see how with current set up.

Ah well a bit of wire extending to do tomorrow I guess