How early is your 850?
There is alot of info on other forums for early mini 12v fuel senders.

http://www.minimania.com/msgThread/1097 ... _questions

http://www.mk1-forum.net/viewtopic.php?t=8873&p=65880

http://www.theminiforum.co.uk/forums/to ... ght-to-max

ROTFL!! If, as in another story, the vehicle inspectors and traffic police (in combination) couldn't spot an after market add-on down the back of the engine in another vehicle, then I'd be surprised if any judge would spot the earth screw.

thanks all, i only just got the old girl running today.

I had some dodgy connectors going into the sender, lots of piggy backing different connectors, not sure what happened there. Anyway the fuel guage its reading full, off the charts full. all the way to the right and beyond.

I didn't see a little voltage stabliser behind the speedo. Its a 1965 mini 850, its strange though. It reads 9.5 at the tank / sender but behind the speedo it was closer to 11v?

i have a feeling i have a little electronic stablizer i got off one of the forum members years ago, does that make sense? i'm trying to remember.

i'll read through the forum previous posts and see how i go, i can see there are a few troubleshooting bits i can through to eliminate bits and pieces.

Original voltage stabilisers can get funny when old.
My fuel gauge used to drop the faster I went. Then when stopped you could watch it come back up.
It was body vibes. They use 1950s vibrator technology.
A new electronic one from wombat fixed it.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I have a similar issue at the moment, guage level drops to empty once I start moving but I already have one of wombats stabilisers. Any other possible causes?

Yes I am back..I hope much much more...sorry about all the absences.

The voltage 10v stabiliser correlated to minis with generators. The 12 volt generators are a luddite vresion of creating 12 volts, so as the engine speed changed the voltage out varied greatly too.

To prevent the gauges roving up and down with the change in voltage, the stabiliser reduced the voltage to a steady 10 volts which remained as such no matter what the generator chose to put out, which was normally always higher than 10 volts.

After Alternators came in which put out a rock solid 12 volts because of their modern and reasonably efficient design, the stabilisers remained for a while as the instruments were all created for 10 volts, and still needed this.

You will note that many modern equivalents of our Smiths gauges are 12 volts, as they were designed for fitment in all kinds of cars, not just BMC, so don't require a stabiliser. Often people get caught in this trap when they fit these modern equivalents in place of their defective originals.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

+1 for dropping fuel gauge reading and temp reading the faster i go.