Temp gauge and water pump mystery

[Odium]

I've started riding my Vision as my main transportation as of this week. A couple days ago it started a strange behavior. The temp. gauge seemed to be reading correctly, it would go to about mid way and go up and down a little as the fan came on or off. Then it just started getting lower and lower, until it went down to the bottom line. When I got home I noticed there was a lot of coolant coming out the water pump weep hole, and I could see where it had been evaporating on the exhaust during my ride.

My first thought was that I was totally out of coolant and that's why it was no longer registering the temperature. I checked the radiator and the overflow tank and they were both full. Since then, whenever I ride the bike, the temp never goes up past that bottom line. The fan comes on and off like normal, so I assume the thermostat is working. Could the gauge just have failed? I checked the electrical connections too and everything looks good.

[Extent]

Well the temerature guage sensor and the thermo switch for the fan sit by the air breather just under the gas tank.  If the sensors are sitting in an air pocket they won't read anything, but you say your fan is working...

[jasonm.]

1) your water pump seal(s) are bad. Must be replaced. Not fun. You must remove the entire right engine case. (2)Also get a new crankshaft seal. Which sits in the case. These often get recked when removing the cover. Replace the mechanical water seal and water pump shaft oil seal. A service manual is recommended! I have done it on a few visions. The waterpump seals are the same as a Venture or Vmax.The crank seal is Vision only. The gauge issue, is a loose wire likely. Happened to me once. good luck.

[Odium]

Was your problem with the gauge the connection in the headlight? Or at the thermostat? I've disconnected and reconnected everything in the headlight a couple times and it doesn't seem to help. Maybe a pinched wire somewhere, or just a lousy connection. I'll take a look and see if any of the leads look oxidized.

[jasonm.]

in your instrument panel the wires are screwed to terminals. The screws can be loose. I suggest you remove the instruments. Remove the back and check screws on the terminals. Or simply clean lugs lightly with sand paper and reattach. Yes, mine was the nuts,screws/lugs being loose. screws are brass, the lugs and nuts are not, you'll see.