Fuel transfer repair.

[Cuppa]

Update - with a bit of useful info for anyone who suffers the same problem of the subtank gauge not working & the fuel transfer being disabled.

Had an auto sparky look at it last week.

I thought he was pretty switched on (pun intended).

Rather than dropping the tank to get the sender unit out, he went to his office to get a paperclip, then got under the car & disconnected the the wiring from the subtank at the connector. He told me that if he then placed the paperclip between the contacts on the 'car side' of the the connector & turned on the ignition that if all was ok forward from that point that we should see the sub tank needle go up to register full.

Sure enough with ignition on the sub tank needle slowly went up.

So this appears to confirm that the problem is that the sub tank sender unit has sh*t itself as I suspected. Tuck that little test away for future reference if you think it may be useful.

Prices for replacement sender units were a bit eye watering from around $450 to $500! No such thing as 'aftermarket' that I could find. Different for the deeper 85 litre sub tanks that the utes have. (Same for TD42 as for 3.0l models)

screenshot_2161.jpg

However I managed to score one on a 'deal' off an ebay seller in Qld for $303.00. Paid an extra $5 for express delivery on Monday arvo & it arrived here (Vic) Wednesday morning. I was impressed by that.

Will be fitted next Monday morning. Hopefully will resolve the transfer issue.

[mudski]

Yeah great info there mate. I will put that trick into the memory bank.

[Cuppa]

Woohoo! We have a fully functioning sub tank fuel gauge & fuel transfer system again.

Once the tank had been dropped & the sender unit removed the problem was pretty obvious.

The entire float arm had detached from the main unit.

New unit fitted & all is as it should be. Happy days.

screenshot_2164.jpg

[mudnut]

Does bypassing the sender unit also work to get the pump running?

[Cuppa]

Does bypassing the sender unit also work to get the pump running?

A very good question. I'm not sure, but it would be good to know, Could have saved a fair bit of siphoning with the jiggler hose on the Old Telegraph Track!

I've read that if you can zip tie the float up at the top so it reads full & that this will allow the fuel transfer system to work. Obviously in my case that wouldn't have worked, & even if the the float hadn't of broken off, dropping a full 85 litre tank would have been a non starter.

BUT when the auto electrician disconnected the sender unit connector & put the paper clip between the two contacts on the car side I should have checked to see if doing that (The subtank registered full even though empty) enabled the transfer pump to work . (After disconnecting the crank battery to reset it). It would be a very handy little trick if it works. Couldn't do any harm to try.

[mudski]

Does bypassing the sender unit also work to get the pump running?

The senders work off resistance. Or different levels as the sender float goes up or down. If you could mimic this somehow I’m sure you could get the pump to work


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[Brissieboy]

The senders work off resistance. Or different levels as the sender float goes up or down. If you could mimic this somehow I’m sure you could get the pump to work


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Need to be a little careful doing this. The transfer also needs to stop when the gauge indicates empty and that will never happen with a bypass or tied up float.

[mudski]

Need to be a little careful doing this. The transfer also needs to stop when the gauge indicates empty and that will never happen with a bypass or tied up float.

Correct. but if it were for emergency purposes to just get some fuel into the main tank, manually watching main tank levels would be a must.

[MudRunnerTD]

@Winnie @AB both have fitted long range sub tanks to their GQs without the factory transfer setup. I think they both just have an in-line pump and time it manually. They borh set it up for the Meetup in the middle 10 years ago. They dont have a factory guage.

[PeeBee]

@Winnie @AB both have fitted long range sub tanks to their GQs without the factory transfer setup. I think they both just have an in-line pump and time it manually. They borh set it up for the Meetup in the middle 10 years ago. They dont have a factory guage.

I had my belly tank running out of a 5 port valve, so what went from the tank returned to the tank on fuel return circuit. I had difficulty getting every drop out of the tank, so converted it to a transfer pump to tank set up and whilst it still had its own matched VDO gauge and sender unit, I just operated it via watching the fuel level rise in the man gauge. Worked flawlessly, and with in line filters the transfer pump was protected from the sludge and dust that gets into the fuel. The additional gauge was handy from the perspective it gave me an indication of the level of discharge. The pump was a cheapie and a diaphragme type from memory and didnt mind running 'dry' but in essence it had a coating of slimy diesel so all good.