Jiggle valve?

(remove)sound · 2004-02-10T15:55:53+00:00

What specifically is a jiggle valve as it relates to a thermostat?Specifically, how it relates to a ford 3.0 vulcan. The shop manualsays position the jiggle valve in a certain position, but it doesnot define what it is. Can someone enlighten me on this?Also, can a thermostat be put in wrong if its not at a certain orientation? What are the symptoms if its in wrong?Short story, last fall i changed out the radiator, water pumpand thermostat in my 93 taurus 3.0. (radiator was leaking)The car runs fine, but the temp gauge on the dash slowly climbs to 3/4 of the way, then jumps down to about 1/4 of the way on occasion. Its not missing when it goes up 3/4. Its not in the red and below the edge of the hot mark.I think i did not check for a jiggle valve orientation when i installedit last fall. that's why i am asking. I also wonder if the first speedof the two speed radiator fan is out if it could cause this problem.The other thing i noticed was the OEM ford thermostat had a small holein the plunger. The replacement did not. Does this little pressure EQ hole (or what ever it is) affect operation? What's its purpose?Bob