Fuel Gauge Sender

[alan]

I was helping a friend last weekend to try and find the fault with his fuel gauge (VDO) which is reading permanently full. Took the sender unit out of the tank and cleaned all the gunge off it, but it still read full. Measured across the unit with ohmeter and got resistance but when moving float there was only a very small kick on the meter about mid range. Boat was a Beneteau 311 with Yanmar engine, and gauge/sender are by VDO.

Am I right in assuming the gauge is a moving coil meter and the sender is a variable resistor??

Ran out of time last weekend and had to put it back as was without being able to fully check it out. If anybody can give me some info or point me to a VDO web site which has some technical info then I would be very grateful.

Thanks in advance.
Alan.
Nettuno, Italy.

<hr width=100% size=1>Alan Cloke

 

[andyball]

vdo user manuals for modern types are <A target="_blank" HREF=http://www2.vdo.com/vdo/end_consumer/ec_product_and_fza=_and_ID=889.aspx>here</A>

Most guages I've seen work as you think....does the needle move right up/down if you disconnect the sender?...If not, look in the wiring/display

<hr width=100% size=1>

 

[alan]

Thanks a lot, Andy; that is just what I was looking for.

Alan.

<hr width=100% size=1>Alan Cloke

 

[DepSol]

It may just need recalibrating in other words setting up so it knows whe the float is at te top the tank should read full and when at the bottom empty.

<hr width=100% size=1>Dom

<A target="_blank" HREF=http://www.soltron.co.uk>the website</A>