The cleaning process of the Fuel Senders: Lib Wagon

__JC__ · Post by **__JC__** » Sat Jan 05, 2008 1:40 pm

nncoolg wrote:...Has anyone tried moving the contact that 'wipes' around the contacts on the white card, so Its touching a brand new part?

I have never had mine (S2 AWD Legacy) out, so I honestly dont know if it's 'do-able' or not, but interested!!!

That should work in theory, similar process can be used to fix vane type air flow meters too. Guess is just depends on whether the contact on the arm is worn aswell.

nncoolg · Post by **nncoolg** » Sat Jan 05, 2008 3:33 pm

Yeah, I think if the arm contact was a problem it would either work, or it wouldn't, instead of being a problem in a particular gauge position.

Maybe, it is possible to get a replacement board. When I had one of the above mentioned 'Flap' AFM-equipped RX, a guy replaced the carbon board in the top of it, no-idea where he got it from though!

...Has anyone got a worn-out sender to donate to me for trial...?

SUBYDAZZ · Post by **SUBYDAZZ** » Mon Apr 21, 2008 10:31 am

nncoolg wrote: ...Has anyone got a worn-out sender to donate to me for trial...?

I may have very soon if you are interested, I picked up a bargain at a wreckers, pump & sender complete, but it is out of a sedan. Punting it is the same as my wagon's main sender, either way when I get around to testing it / fitting it (read: couple of weeks or so) I can send whichever I don't need if you can pay for postage. Let me know if still interested.

SUBYDAZZ · Post by **SUBYDAZZ** » Fri Apr 25, 2008 11:10 am

I can't see why Subaru can't supply the senders as a separate part to the pump because with 2 screws and a plug it comes undone from the assembly.

Anyway, I've written here because I have had some real success with cleaning a donor sensor I have pulled out of a FWD model.

I whacked the multimeter on the terminals for the sender to see if the resistance was within tolerances found in the FSM.

For FWD this should read between 2 and 5 Ohms at Full and 92-95 Ohms at Empty. To be kind it was a fair way out (too high) and on moving the sender the resistance certainly didn't change gradually between as expected (some points there was way higher). I cleaned the circuit board with some contact cleaner and it made little difference.

This is when I had a brainwave: Since the resistance is too high, perhaps a bad contact is being made elsewhere? I pulled apart the mechanism which consisted of a copper spring and contact that goes from the circuit board to the sender arm to complete the loop by sliding over the circuit board if that makes any sense. I cleaned up the ends of the spring, and the contact point and the other copper contacting areas with some very fine emery paper, and gave a light sand on the contacting parts of the circuit boards as well. And what do you know - it's now exactly to specs!

Now since in the 4WD model there are 2 sender units, with the resistance of each adding to become the same as the 2WD unit (conveniently), I might have a play with the units in mine and see if I can bring them back to spec, and if not, I may see if I can rig it up to work with just the 2WD sensor. I also hope to check if the Low Fuel light thermistor is working in either of these units I have to see if I can get it to work right (never worked on mine at all).

Stay posted.

SUBYDAZZ · Post by **SUBYDAZZ** » Fri Apr 25, 2008 5:22 pm

OK, Plan failed. The sender units in my car are worn through, this unit I picked up isn't. Anyone need a good, cleaned sedan sender? Also the setup for FWD won't fit in the 4WD tanks as I'd hoped.

I think what needs to be done to replace these units is to find someone who has PCB design and small electronics skills to create a series of contacts in a certain arc shape on a board with small resistors between each to step from 2-5 Ohms to 92-95 Ohms for FWD senders, and 0.5 to 2.5 Ohm to 42-44 or 50-52 for 4WD models (sub and main).

I'm sure this can be done, but yeah will need someone with the skills. I'd pay good money if someone can develop one.

vincentvega · Post by **vincentvega** » Sun Apr 27, 2008 8:12 pm

dazz. remove left and right boards from a wreck and send them to me and i will see what i can do about replicating them. designing circuit boards is what i do..

Matatak · Post by **Matatak** » Sun Apr 27, 2008 8:13 pm

http://cgi.ebay.com.au/Subaru-Fuel-Send ... dZViewItem

buy a new one?

SUBYDAZZ · Post by **SUBYDAZZ** » Mon Apr 28, 2008 4:28 pm

vincentvega wrote:dazz. remove left and right boards from a wreck and send them to me and i will see what i can do about replicating them. designing circuit boards is what i do..

May as well send you mine, as they aren't much good to me (I just go off the tripmeter now), I can't think of anything bad that may happen if I take them out anyway.

Re: The eBay listing, I doubt it would fit most 92-98 Subaru as it says as it looks well different to all I have seen.

Especially now I find out that even the 2WD senders are different to the 4WD ones.

vincentvega · Post by **vincentvega** » Mon Apr 28, 2008 4:31 pm

pm'd you dazz

SUBYDAZZ · Post by **SUBYDAZZ** » Tue Apr 29, 2008 9:19 pm

Matatak wrote:http://cgi.ebay.com.au/Subaru-Fuel-Send ... dZViewItem

buy a new one?

Re: eBay sender that suits most 92-97 Subarus.

My sources indicate to me that it doesn't suit SVX, Fiori, Impreza, L-Series, Sherpa, Forester, Outback or Brumby from that date range, but it does suit a 97 model Liberty (but no earlier year models). How's that for an accurate description?

Bumpty · Post by **Bumpty** » Tue Apr 29, 2008 10:13 pm

haha, nice description Dazz!
Bad luck with your sender units by the way... I think I'll just get new ones, if my tripmeter ever dies hehe. Let us know how the do it yourself circuit board goes, which undoubtedly ya will

SUBYDAZZ · Post by **SUBYDAZZ** » Tue Apr 29, 2008 10:33 pm

vincentvega wrote:pm'd you dazz

And I emailed you

Bumpty wrote:haha, nice description Dazz!
Bad luck with your sender units by the way... I think I'll just get new ones, if my tripmeter ever dies hehe. Let us know how the do it yourself circuit board goes, which undoubtedly ya will

$249.65 for the main sender and $165.10 for the sub.