VDO Fuel Sender

VDO Fuel Sender

Author
Discussion

Grady

Original Poster:

1,221 posts

259 months

Monday 12th June 2017
quotequote all
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


Alpha Omega

11,209 posts

108 months

Monday 12th June 2017
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If the fuel sender internal wire is damaged you can repair it
Search Ebay for NiChrome Wire and use it for a re-wind
Here is a very good tutorial - https://www.thesamba.com/vw/forum/viewtopic.php?t=...

Anything mechanical wrong with it is easily repaired

Grady

Original Poster:

1,221 posts

259 months

Monday 12th June 2017
quotequote all
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?

adam quantrill

11,535 posts

241 months

Monday 12th June 2017
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You could simply use a resistor instead of the sender and if you gauge shows 1/2 you know you're probably half-way there....

gmw9666

2,734 posts

199 months

Monday 12th June 2017
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Grady

Original Poster:

1,221 posts

259 months

Monday 12th June 2017
quotequote all
gmw9666 said:
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. smile

gmw9666

2,734 posts

199 months

Monday 12th June 2017
quotequote all
Grady said:
gmw9666 said:
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. smile
And there's me thinking a wedge was a macgyver motor lol

Grady

Original Poster:

1,221 posts

259 months

Monday 12th June 2017
quotequote all
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.

Alpha Omega

11,209 posts

108 months

Tuesday 13th June 2017
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Dont use seperate resistors, use a variable resistor

http://www.ebay.co.uk/itm/25-Watts-High-Power-Wire...

Grady

Original Poster:

1,221 posts

259 months

Wednesday 14th June 2017
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I was thinking of that. Ordered one from Prime today.

pasogrande

375 posts

256 months

Wednesday 14th June 2017
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Hi Grady,

To answer your original question, you may want to talk to Lauderdale Speedometer at 800.951.5123 https://www.lspeedo.com/

They seem to be very knowledgeable about all instruments and gauges including VDO. However they specialize in marine, and are not cheap. But they should be able to give you an answer - free.

Good Luck,

Wilf.

Grady

Original Poster:

1,221 posts

259 months

Wednesday 14th June 2017
quotequote all
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?

MCWEDGE

56 posts

85 months

Wednesday 21st June 2017
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Grady,

Try this link; you're a member, right?

http://www.tvrccna.org/members/tvrccna.pl?page=280...

Gist is, contact:http://www.nhspeedometer.com/

May not help you to have a replacement in hand when you pull the old one out, but still may be a viable solution.

Jim

Grady

Original Poster:

1,221 posts

259 months

Thursday 22nd June 2017
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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.

MCWEDGE

56 posts

85 months

Thursday 22nd June 2017
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Grady said:
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.
I'm still using the same password as last year. New password came in email from Terry Telke on 3/8/2017, but I haven't had to switch to it.

No guarantee that your VDO sender and the one in that article are the same, but his was a "10 ohm empty, 180 ohm full sending unit."

Jim

John042

892 posts

168 months

Tuesday 27th June 2017
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Hi, I've a similar problem with a 1984 2.8i fuel tank sender unit. Mine seems to be a mechanical problem. It was removed the arm freed up and it worked OK for a few weeks but has now stuck again at 1/4 full. Rather than remove it again to try and prevent it sticking I would like to replace it. Are the senders available? Thanks J C.

mrzigazaga

18,534 posts

164 months

Tuesday 27th June 2017
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Hi John


From what I have found it seems that to get a real true reading of the amount of fuel in the combined tanks would mean fabricating an arm on the sender to read the lowest point and then the highest...

For example: I used a classic mini fuel sender for my 280i and it would read the full tank perfectly but when it got to under half a tank...Well thats anybody's guess...Its quite funny to be at panic stations on empty only to pull into a garage and have the petrol miraculously appear to just under half after 10 miles...hehe

Then there are senders with shorter arms...They read the lowest point accurately but fail over half full...These tend to encourage people to overfill.

So as they say me ole china..."The choice is your's"...smile

(Please be aware that there is a danger that I'm talking twaddle)

John042

892 posts

168 months

Tuesday 27th June 2017
quotequote all
Thanks Mark and Hi. I thought I'd cured the wiper arm sticking, obviously not. It's a pain to remove the sender so this time I would like to positivly fix itmad The point where the arm enters the unit seems to be the problem. Lubrication soon wears off so thought a new sender would be the way to go? Is it by chance a BL Mini sender?
Also Mark can I open another "Can of Worms"spin 2.8i clutch cablesbiggrin I've just read some of the old posts on the subject; very interesting. However no definitive answer as to type or number. Best option being to get one made? Cheers Mate John C.

mrzigazaga

18,534 posts

164 months

Tuesday 27th June 2017
quotequote all
Hi John


As Andy say's, Im sure mine was a cortina...Here is a selection that could work...Best to check the length..smile
https://www.google.co.uk/url?sa=t&rct=j&q=...

John042

892 posts

168 months

Wednesday 28th June 2017
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Thanks Mark/Andy for the info' on fuel senders and clutch cables. Good point on the sender float, I got caught out once with a MGB carb' float and an overfueling problem. Winter task then, to remove the sender "Again" Cheers all. JC.