Derek: You're right, the switch is grounded through the threads to the water pump, take the tape off, the sealing ring should be enough to keep it from leaking. You can put a continuity tester between one of the leads on the switch and a ground point and if the engine is colder than 95 degrees it will show continuity. I can't say which lead is the ground one, they both look the same, the other is from the starter solenoid to prevent flooding. Current from the starter solenoid during cranking heats a bimetallic arm in the switch to break the ground connection, thus disabling the cold start valve. Take a look at the technical manual for a schematic of how the switch functions, it's pretty simple. Todd Nelson 1561, Vermont http://www.rit.edu/~tan5732 ----- Original Message ----- From: "Derek" <derek.grozio@xxxxxxxxxxx> To: <dmcnews@xxxxxxxxxxxxxxx> Sent: Sunday, June 25, 2006 11:41 PM Subject: [DML] How does the thermotime switch work? >I recently did a valley of death teardown and now the car seems to have >problems starting > when cold. The only thing I really touched thats involved in the hot/cold > start circuit from > what I can tell is the thermotime switch. I removed it from my old water > pump and replaced it > in the new one. My question is, does the switch threads use the water pump > as a ground? I > put teflon tape around the threads before reinstalling. This is my only > idea so far, as I do not > know how this circuit works (what is being sent and triggered by the > switch) and haven't > pulled out the multimeter yet to check it. Any comments are appreciated, > thanks. > > -Derek #10084 To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/