[C320-list] Perkins 30 temperature gauge malfunctioning

[Clay Carter]

My 1995 Perkins 30 has recently had some temperature gauge issues.  First I found the wire had broken loose from the sending unit—fixed that and the gauge was working again.  Not it has failed yet again—I checked the wiring and it is good this time.  I noticed the temperature gauge moving up, then it suddenly dropped to zero. Would you be suspicious of the sending unit, gauge or other?  How do you test a temperature gauge?

Thanks for any input.

Clay Carter
We’ll Sea #225
Alamitos Bay, CA