Eureka : Fuel Gauge repair

Another item I wanted to tackle is the failing fuel gauge. I don’t recall where I read it, but someone else also bumped into this issue and the permanent fix was to replace the fuel tank sender unit with the floater attached to it. On one of the Jaguar fora I also read these appear to be often flakey or having leaky floaters – which is not unusual since the car has aged.

So without doing any pre checks or testing I simply took the gamble and ordered this item. Including a new rubber gasket. Total costs including shipping € 51,-

I’m still amazed how much information can be found on this car. In any case it’s very useful and makes things easy. Rather then fiddling around or patching up the old unit I figured to buy it entirely new. And yes, I consider this item very affordable. If it turns out not to be faulty then I consider it preventative maintenance and I can rule out any problem with it for a long time.

The previous owner told me he ended up once at the highway with an empty gas tank. Clearly a situation I want to avoid and I don’t like to fill it up every 200 kilometers as I’m unsure how much is left. So time to get this fixed now.

The item itself is surprisingly very accessible and behind the spare wheel as that's where the fuel tank is located.

Also the fuel filter is located behind the spare wheel, good to know.

Removing the carpet and presto

And here it is. Picture taken to remember the wiring to the right connectors

Before replacing I did check the functionality first. Here with the current faulty one:

And here the new one, I simply connected the wiring on to it and lifted the floater. And it works perfectly so fault localized and I can go ahead to get the item replaced.

But as I have no clue how much gas is left in the tank I must first drain it.

I’m using the old skool trick to drain it, meaning applying the law of interconnected vessels. I still recall this vividly when our physics teacher explained this matter in 2^nd grade at the age of 14. Of course he brought up the fact this method was being used to steal gas. He also mentioned it’s a tricky job as you can’t see the gas coming. I then advised him to use a transparent hose, which caused some raised eyebrows. I just happened to be very experienced in this matter as I grew up next to a garage. As youngsters we could play around and actually drive wrecked cars. And for this we needed gas which we simply drained from other wrecks. First lesson learned was to blow and listen if it had gas at all. Else you would sucking gas damp for a long time and I can reveal it will give you a nasty headache. Second thing we learned that gas flows very quickly and if to late you got it in your mouth. And I can reveal it taste exactly as it smells and it takes a long time to get rid of this taste. As such use a long transparent hose that allows to anticipate on the timing.

Removing and replacing the sender unit was another easy job.

 The removed unit was in a poor condition and heavily corroded. The floater itself was ok though:

But the pin attatched to the floater and the sender unit was completely stuck and wouldn't move at all. Thus explaining the failure. Not a surprise since the car was parked for 12 years in a showroom.

To avoid potential leaking I placed a new rubber seal

 And placing the new unit back into it

Then refilling it. I had already a full can of gas drained which I put it my other car. On the 2nd drain I think another 10 liter came out of it. So I did put that back and turned on the igntion. The meter went up but only very little. Hmmm. So on to the gasstation to do a proper refilling. To my surprise the meter didn't move up at all. Wicked. I now wonder what went wrong?

So now I will use the car for the rest of the week as a daily driver to empty out the gastank again. Sigh. Hopefully next week I can find out what's wrong.

Update 20-9-2016 : After touring around for the past 4 days I have ran into some trouble 3 times today! I will write a seperate blog about that. But just when I stranded for the 3rd time I noticed my fuel gauge was working all of the sudden. Not sure what happened though. As written earlier, I tested the functionality of it before installing. And I was pretty convinced I did everything properly. Apparently I did but still something must now have triggered it to start working. Weird. Here is the proof

Update 6-10-2016 : I came across this brass floater. Thought it was interesting to share

http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=108826