Fuel starvation, towed home by AA, help needed

[T-Cut]

I'd avoid power-on operation of the float arm/rheostats with the filter module in the tank port. There's a possibility of generating a spark as the rheostat contact brush is moved over the windings. The situation is different when the units are operating in the sealed tank. You can get the gist of this HowTo by rich17865 but the missing photos don't help. Unfortunately, he seems to have left the forum so chances of their recovery are slim.

You might try the Trip Screen Diagnostic routine to see if that gives an indication of a faulty rheostat. https://www.the75andztclub.co.uk/for...ad.php?t=55585

See section 6

TC

[StewartIngram]

I had a quick check both sides today to check the floats, before the rain started.
On the pump side, nothing seemed amiss. But on the filter side, 2 points. The float could have had its arm restricted by adjacent tubing; I've tried to re-insert it with the tubing away. Also, what I guess is the pick-up pipe on the filter assembly, the one with the blue plastic small filter on the end, is on the end of a metal arm with a plastic clip on the other end. The latter was completely detached from (what I assume to be correct) its location on the side of the filter body. It is now clipped on.
Before I started, with approx 40 miles motoring today, the 1st 15 or so on petrol, the gauge has dropped from 1/4 full to about where the low level light comes on. However, the tank has both sides filled to a high level. I still have no change with getting both floats reading; I have done the dashboard check which confirms a fault on one side.
When it dries up outside I'll get my meter and a pin, and take a reading on each float lead, should be easy pricking through the insulation and save stripping the tank apart for a while.

[gnu]

Keep on posting Stewart. You’re not the only one with fuel tank woes. My fuel gauge can’t always be trusted, and looking at yours wonder whether a pipe is poorly routed as it seems to stick if I brim the tank. Totally ran out of fuel a few weeks ago on a family member whilst indicating 1/2 tank! Looks ok atm after taking routes with speed bumps.

I hope running it dry hasn’t damaged the pump.

[StewartIngram]

It seems I may have got to the root of the problem now, problem will be getting spares.
Dashboard diagnostics confirms that only one float/rheostat is being read.
RAVE shows the connector to the top of the pump to be C0114, with a diagram; relevant pins are:-
1, Green/Brown, linked in the loom to pin 3.
4, Green/Black, connected to the ecu to feed the fuel gauge.
6, Black/Slate (Grey), connected to the ecu to feed the fuel gauge.
Also, (but not related to the fuel gauge) -
2, White/Purple, ign +ve to the pump? (I haven't checked this).
5, Black, connected to chassis/ -ve (earth return for the pump?

Delving into the circuit diagram, I found on the fuel gauge page that the RHS float is connected across pins 1 & 4, with the LHS across 3 & 6.
With the plug in place the ecu/fuel gauge sees them both as 1 & 3 are linked.
Unusually for RAVE these 2 small bits of info are all I can find on the workings of the fuel tank!

With my meter I checked the LHS (3 & 6) and got a reading of about 141 ohms for approx 3/4 tank of fuel.
But the LHS (1 & 4) showed as open circuit. For me, that simplifies things a lot, being an ex electronics guy! So next I removed the pump, as much as possible. I found it impossible to get it right out of the tank due to pipes, float etc, but with the aid of a small mirror & torch I could see under the top connector, and trace the wires. There are 3 green ones from the connector, 2 of which go down to the float rheostat tags, I was able to check the continuity of the wires to those tags as ok - which are the ends of the rheostat. With a torch, I then managed to see what I am sure is the wiper of the rheostat, lying on the floor of the tank. I don't think that I can refit that, especially in situ, so the repair has to be replacement.
Btw plenty of petrol confirmed in this side of the tank (at least).

Now, until I manage to get a replacement, I hope the lack of fuel measurement does not stop the engine from working. As, apart from starting on petrol, I shall be using lpg, what is in the petrol tank should last quite a while.

Thanks to everyone for their input, I've learnt a lot, and will post again with any developments.

Anyone got a replacement float/arm/rheostat (I believe the assembly is held by 2 screws), or if necessary, a complete pump?

Stewart

[StewartIngram]

Edit to add:

The 2 screws are actually 4, and I cannot reach the bottom pair!
I have however retrieved the (phosphor-bronze?) wiper from the tank

[T-Cut]

Originally Posted by StewartIngram

I have however retrieved the (phosphor-bronze?) wiper from the tank

Interesting. Looking at the wiper, has this broken/fatigued off its mounting or has a fastener failed?



TC

[StewartIngram]

In all honesty, I think it is an own goal, either by me or Mr.AA, wriggling the pump around. I have the little wiper here in front of me, but can't get at the rheostat to see how it clips on.

[T-Cut]

Here's a photo from way back. Looks like the wiper is fixed to the white plastic bit that the float arm clips onto.





By the look of it, I'd say the white bit clips into a 'bush' on the case in which it rotates/moves up and down. You may be able to reassemble it with a bit of luck.


TC

[p2roverman]

I've been through all this recently, pump and filter out etc only to realise the only reason why the car would not run was too little petrol in the tank.
Then compounded the problem by snapping the platic bit at the end of the supply pipe whre it goes into the filter - replacing that full length is a bit of a fiddle and is a temporary job unti I rebuild this car properly

[StewartIngram]

Looking at that pic, the square grey plastic, with the rheostat in the middle, looks as though it might unclip, leaving all the white plastic (held by 4 screws) behind. Now if I'm right, the arm can be pulled out of the tank, and maybe, just maybe, the wiper fixed on?