Otterstat question

[David T]

Erratic behavior by the "O" switch can also be caused by air in the system and/or a bad thermostat. The thermostat is supposed to open before the "O" switch turns on the fans. Also if you have the very early plumbing you should upgrade it to the later style where the "O" switch is on the bottom of the pipe. While the "O" switch is fragile, once installed and working satisfactorily, it should last a while. My guess in your case, the thermostat is not opening and closing the way it should. Typically a bad "O" switch won't turn on the fans. A thermostat stuck open won't keep the motor at operating temperature, ie, it never warms up. It is supposed to stay closed till it gets to 180. Replace the thermostat and rebleed the system.

[DMCMW Dave]

I've also found that seriously overheating the engine will damage the otterstat. You'll find this out when you get it cooled off, filled back up, and bled, and the fans no longer come on.

Although sometimes it may be that the otterstat failure caused the overheat, so it's hard to tell for sure.

And where Bitsyncmaster mentions removing it, he really means disconnecting it. If you remove it you have a huge leak in the coolant pipe!

[kbrown84]

i have used the modern "otterstat" from DeLoreanGo on my car for the last 6-7 months...its worked flawlessly, and seems to very robust in quality. otter.JPG