Fuel gauge..sender?

[allan]

Hi All,

My fuel gauge has been playing up for some time and I suspect the sender unit. Looking in the manual it does not say whether it can be changed without removing the fuel tank. Has anyone been able to do this or is it the "full" job?

 

Thanks, Alan.

[CraigAddison]

I've only done this when replacing rusty tanks, I think there is enough room to do this without removing the tank, I'll have a look underneath when it's daylight.

[allan]

Thanks Craig, was it difficult to remove the tank when you did it? I expect a pit would be required to make the job easier...?

Alan.

[Guest Ric.7]

Hi allan

It is possible to change sender with out removing tank, just dont do what i did and change with a load of fuel in, its messy.

[CraigAddison]

Removing the tank is a pig of a job, it requires dropping the rear axle so you can get the tank out, you'll also need new support straps & fixing studs & nuts as these will almost certainly be rusted, as might the filler neck bolts. I've replaced 2 tanks now & in both cases had to cut the support straps, remove the tank & then attack the rusty studs, refitting is relatively easly. Allow a weekend & supply all those in close proximity with earplugs so as not to be offended by the frequent and colourful language!

[Guest pilbaratr7]

We are lucky here in Australia, not much rust. I have my fuel tank out at the moment. I have just silver soldered a return to tank fitting for the 3.9 rover EFI v8. I was amazed at how clean my tank was after 25 years, no crud in the tank at all. My tank came out real easy. I had one tight nut that was trying to twist the strap but the rattle gun fixed that. My float on the sender unit was 1/3 full of fuel so I have replaced the float.

Anyway you will be able to replace the sender unit with the tank still in the car. Just make shaw the tank is near empty. To remove the tank you have to remove the rear axle.

 

Glen.

[allan]

Thanks for the info all. Looks like I'll have a go with the tank in situ. Before I start I need to be sure it is the sender and not something else. The problem is that the gauge sometimes shows full when there's not much in the tank and empty etc when there's a lot of fuel. It also fluctuates all over the place at will! Could it be anything other than the sender?

Thanks for any help, Alan.

[rayjones]

Allan,

 

I've noticed that mine goes right down to nearly empty, and the low fuel lamp comes on if you go round a r.h. bend long enough and fast enough, but seriously though I would think that perhaps the low fuel indicator might give you a clue as to whether the gauge is OK as I guess that is triggered by the sender too. i.e. if the indicator was on, but the gauge is reading high, you have something wrong with the gauge, rather than the sender. Also if you disconnect the sender wires from the tank, the gauge should either show fulll deflection or empty, one or the other anyway. If you shorted the two wires together, the opposite reading will be shown! Hope this helps

 

Ray

[allan]

Thanks Ray, that certainly makes sense. I'll try that on Saturday when I can get the car into the garage. Whatever I finally do to fix the problem, it's going to be extreamly difficult to get too whether it be the tank or gauge.

Regards, Alan.

[Guest ajttriumph]

The problem will be fuel in the float not the sender.

[andrewt]

I'm not sure if this is the case or not for the 7, but if there is a voltage regulator on the gauge & it is wonky, then this will influence the fuel gauge as it is simply a voltmeter reading the resistance from a known (regulated) supply to earth via the variable resistor in the sender. Also check out the wiring connections etc onto the sender as these are spade connections which are open to the environment. these are directly above the prop. Check these out before removing aything else.

 

Andy

[Guest john-egerton]

Allan,

 

This article may help you: Fuel sender replacement

 

John