Petrol Tank Sender Unit and Dashboard Gauge

[chris dancey]

My next item to sort on the 10hp Coupe 1938 is the petrol gauge sender unit / dashboard gauge. The petrol gauge does not register although the tank is full.

I have made various tests but cannot get to the bottom of the problem. I intend to visit a friend of mine who has a multimeter ( mine is broken ) to test the resistance of the float unit, I still think the problem is with the gauge.

Does anyone know of a company who specilises in the restoration of these items, I would prefer to restore the originals but would go to modern alternatives if the first option is unavailable.

How has anyone else dealt with this problem ?

[Chris C]

Hi Chris, try the following: http://www.jdo1.com/
they repair all Smiths & Jaeger instruments and clocks
and are not expensive
Rgds, Chris C

1939 - Rover 14

[luli]

The following may help you:
http://www.austin7.org/Technical%20Arti ... 20Working/

[chris dancey]

Thanks Chris and Luli,

I have copies of your site Luli and have used the information included.

Chris I have sent an email to John Ostick at JDO Instruments and awaiting a reply, Thanks for the link.

[chris dancey]

I have also been recommended ' Speedy Cables ' , I have sent them an enquiry email and I will report on their reply.

[lakesrally]

I've also used www.speedograph-richfield.com/‎ who were also ok.

[deckell]

Hello chris i had a similar problem on my p3, so i removed the tank unit and found the float was frozen in the empty position probably was sitting empty for a long period.i managed to free the float arm by soaking it with penetrene and very little persuasion and it then worked very freely .i hope this is of some help, if you have not already done this.regards Derrick.Smith

[David Bliss]

I have been messing about with these for many years, I haven't yet found one I couldn't repair. At the tank end it is quite common for one wire to blow if someone has accidentally fed 12 volts through it, this is usually quite obvious once you unscrew the lid on the top as the wire will be missing from the resistance coil to the terminal attachment screw. A new thin wire can easily be solder in place. Most of the 30's cars use the same units, so it is easy to replace the unit if it is completely useless, some of the units work in the opposite direction so you may need to reverse this before fitting. Occasionally the wiper arm that wipes against the resistance coil get damaged but it is easy enough to gently bend it so that it touches. At the instrument end it is rare to see the two cotton reel coils damaged, but these can be checked using a good multimeter. I have unwound and rewound these coils in the past, you can use a rechargeable variable speed drill to wind the wire onto a piece of wood and then wind it back again. It does not matter if you have to reduce the length by a few inches if one end is corroded. Like all instruments you must treat them gently.

David

[chris dancey]

Thanks Derek and David,

I will be giving this a go, I will let you know how I get on. I will be seeing Derek Field tomorrow at Mark Luffs, he has restored his own.... we are having a ' Rover 10hp ' day...

[chris dancey]

I have sent the petrol level gauge and sender unit to ' Speedy Cables ' I had a very positive responce from Andy Barraclough and was happy with his attention to the problems caused by the sender unit, it would appear that the surface covering of the resistance wire is suspect, so new wire will need to be fitted.

Chris