912 oil temp sending unit location

[HighWing]

Don,
I have had several Westach senders fail on me. What I usually found is a dead gauge. I can give a theory that might explain the bouncing around. The sender is a thermister which is a resister that varies its resistance with temps. It is soldered to the wires and then potted in the brass fitting (the black epoxy where the wires exit. I think the vibrations from the engine can break the solder joint. You might be experiencing the beginning of the end of the sender. I finally ended up making my own and omitting the heat shrink they use which allows vibration to pass to the solder joint. I found more success with the ones I made.
Lowell

[kitfox2009]

Hi Lowell
Does this mean you may be in the sender mfg/sales business. If so, I am interested in purchasing.
Contact by private message if so.
Thanks to you and Dave for the replies.
Cheers
Don