Bongo Fury

Suddenly my temp. gauge has been suddenly going from the eleven o'clock position to zero in a couple of seconds & then back again just as fast. Never goes above 11 o'clock.
Initial thought are a loose wire of duff sensor, I think the system has been bled OK, but I might try it again tonight. Has done 3000 KM since last bled & no problem till now. Any other ideas ???

It could be air locks but it is far more likely to be a duff temp. sender or a wiring fault. I would start with a new sender and then check the wires if that doesn't fix it (unless there is an obvious wiring fault).

It wouldn't hurt to bleed it again just to be on the safe side.

I'm a thicko on these things, but even I think it must be electrical. Which is 'good news' even if some of the leccie things are tedious to fix. Makes you wonder though if you could just write it off and buy one of those devices currently being discussed under coolant level indicator devices (cloggers find of a bolt on engine block temp sensor might be the best equivalent and argualble better than the temp gauge).

Mike