1934-1935 Hudson/Terraplane Fuel Gauge

Old Fogey UK

Does anyone no the correct Ohms resistance for this gauge, please, so I can get a compatible sender unit ?

Old Fogey UK

Sorry, I should have typed "know" - blame my fingers !

Geoff

These are not rated in ohms, but are a bi-metal type. They make-and-break as the thermal strip heats up.

Old Fogey UK

Thanks, Geoff.

So I can't use Ohm resistance type sender unit with an original gauge ?

tigermoth

No. I once tried a Ford sender.. it sends volts, the needle will move, but not in any correlation to the actual fuel level.

there are a couple of places in the states that will attempt a repair of an original king-seeley sender

Regards, Tom

Geoff

I have repaired them but they are tricky, and no guarantee of success.

Old Fogey UK

Surprisingly, I've managed to get the gauge to work with the Volkswagen sender.

All it took was a supplemental earth wire from the sender top to the car body.

The gauge needle went up to about 3/4 full (which coincided with the amount of fuel I thought was in the tank) and I'll see what happens when I next top up the tank.

All this seems to fly in the face of logic, I know, but the sender and gauge do seem to work together !

barrysweet52

Another option is to install a modern sender unit that often come with a matching gauge. Im installing this gauge in the "boot" of my car.

Old Fogey UK

https://openforum.hetclub.org/discussion/comment/253166#Comment_253166

I was going to do the same thing but intended to install a modern sender and a modern gauge on the lower edge of the dash.

However, for as long as the "miracle" of the VW Series1Beetle sender combined with the original gauge lasts, I'm not going to bother ! 😀

Old Fogey UK

An electronics engineer friend has calculated from the information about it in the Procedure Manual (such a feat would be beyond the mental capacity of a mere retired judge like me !) that the resistance of the 1934 and 1935 fuel gauge is 30 Ohms full and 150 empty.

This roughly correlates to the resistance of the VDO fuel gauge used in Series 1 VW Beetles.

He says that it doesn't matter that the two components work in different ways, it's the resistance compatibility that counts.

I used a Series 1 Beetle sender and that's why my gauge now works - so says my savvy friend.

These VW senders are easy to find and are remarkably inexpensive.

bob ward

30Ω full and 150Ω empty is about right. I have a universal sender from Dakota Digital that bolts straight into the 34/35 tank and with a bit of fiddling can be made to get the gauge to read reasonably accurately.

Old Fogey UK

Hi Bob,

What do you mean by "fiddling" ?

Best wishes,

David.

Geoff

Murphy's Law: "If you fiddle with a thing long enough, it will ultimately break".

bob ward

Fiddling involves several steps.

The ohm range provided on the Dakota Digital sender is a little different to Hudson's required 30Ω to 150Ω, fiddle 1 is to alter the stops on the DDS to get the required range.

Fiddle 2 is to wire the DDS to your gauge (have the gauge and sender on the bench or leave the gauge in the panel and sit on the running board with DDS in hand) and move the sender arm from stop to stop and see what the gauge does. Recognise that your gauge is 90 years old and may have been wildly inaccurate when new.

Fiddle 3 is to repeat steps 1 and 2 until you achieve the desired result or patience runs out.

Fiddle 4 is to install the sender in the tank so that the arm still has the same range of motion that it did when you were testing on the bench or running board.

ALWAYS connect power to the gauge ONLY via the sender.

Old Fogey UK

Thanks very much, Bob.

Incidentally, that advice fits in with a YouTube video on how to reconcile senders and gauges.

I might have a go myself but for the moment, I'm happy just to top up with fuel when I hit the 1/4 full mark and then I know I'm safe !