Temperature gauge for an old Volvo Penta MD2B.

[alaskasu]

The needle on the temperature gauge is vibrating. The part for the gauge, #841233 is obsolete and no longer manufactured. Does anyone have a spare, or is there a work around? The temperature sensor #840074 is used on a wide variety of Volvo Penta diesels. Might I just have a bad sensor? Sensors are still being manufactured.

 

[K-2]

It's usually the sensor or also called sending unit. BUT I hate advising a guy to be a "parts changer" without some trouble shooting.
I'm no expert with an Ohm meter but there is a way to test both the gauge and the sensor. Maybe google can help? Have you cleaned the connections and made sure everything is tight.
The sensor is around $50 so it's kind of a $$ gamble if that's not the problem.
I'm in Haines .

 

[K-2]

Might try reposting this in the electronics/electrical forum. Someone there will know how to troubleshoot. A lot more
traffic there than this diesel forum. Good Luck