VDO Fuel Sender

[Grady]

My sender is dead (stuck at 1/2 a tank on the gauge). The VDO gauge seems to work - 0% (empty) if disconnected, 100% (full) if shorted. I'm hoping to have the replacement sender on hand to do this in one pass but we apparently don't have VDO senders over here.

I found a 'adjustable' VDO sender on the UK fleabay but there appear to be 3 possible Ohms ratings. Anyone know the required values or if this one would work? (1986 280i).

Or does anyone know the part number or donner car? Thanks. Grady

[Grady]

Interesting link - might try a DIY job. Any idea if a 0-90+/- ohms is correct of a mid-1980s gauge? (Which would make the sender above the wrong one.) The VW guys were posting about 1960-1970s cars and using 0-70 ohms as a value. I've pinged VDO but don't know if I'll get any help.

Anyone have an extra sender and could measure the resistance for me?

[Grady]

gmw9666 said:

Or match any gauge with any sender

http://m.ebay.co.uk/itm/Gauge-Matcher-Matches-Gaug...

Cool - I didn't even know there was such a thing. Although I would be slightly concerned about adding such a MacGyver device to a Wedge.

[Grady]

That's a good idea. Regrettably the neighborhood Radio Shack just closed (for good) but I need to hit a computer super store which might have resistors.

[Grady]

I was thinking of that. Ordered one from Prime today.

[Grady]

Thanks Wilf.

I've looked at the VDO sender line and each model as 3 senders, one for the 3 common ohm ranges. Hopefully I can figure my out this weekend.

Next question - There appear to be 5 machine screws holding the sender in place. I assume they are tapped into metal tank. Or are there any surprises there?

[Grady]

Thanks - I am a member but need to find the current PW. Sent a request to the site.

Yesterday, I tested the gauge with my cheapo resister and at 0 ohms it showed empty. But at ~33 ohms it was approaching 1/4 tank. At the other end, at ~ 190 it was full and things went south at 200 (max for the resistor). I'm guessing that translates to a 33-220 sender but I guess I'll pull it off and see. Maybe it is marked.

Have to go move my 90 yr/old mother, her cat and kit to Texas this weekend so it will a bit before I'm under the car again.

[Grady]

I would think that the two tanks would eventually equalize so that the measurement in one tank would be the average of two (but maybe not).

Anyway maybe THIS weekend I'll get the sender out...

Last week, I moved my Mom from Florida to Texas. Thought I'd have to put her in a gunny sack with her unrewarding cat. Including packing/unpacking, the longest 13 days of my life (that I remember).

We spent the first night at a friend's apartment in JAX (Jacksonville). Parked overnight on the street because we couldn't reverse out of his parking area:



That is a totally full 26 foot truck towing a totally full Volvo wagon.

[Grady]

Back on topic... Finally found a few minutes and pulled the sender out. Surprisingly, the screws just unscrewed and sender wiggled out with no drama. Making a blanking plate this morning.

The sender itself is stamped "2 85" (manufacture date I assume) and "825/7/13". The outside of the mounting plate is stamped VDO, Made in Germany and "028" The resistance goes from 0-5 (~0 at one end of travel and ~5 most of the rest of the travel). Odd because it always reads 1/2 tank. It doesn't feel like it has a flat spot where it was stuck. The metal resistance wires are bright so I'm think it's been moving.

9" & straight arm

Edited by Grady on Sunday 23 July 17:45

[Grady]

Of course, putting the blanking plate on with gasket sealer was a bh on wheels. Knew it would bite somewhere.