View Single Post
Old 08-26-2016, 06:13 PM   #16
Old Henry
Senior Member
 
Old Henry's Avatar
 
Join Date: Oct 2010
Location: Orem, Utah
Posts: 5,762
Default Re: Installing Bob Shewmans thermostats

Quote:
Originally Posted by quickchange34 View Post
With any thermostat you install always drill a 1/8 inch hole in the middle of the outer ring. It allows a little water through and prevents air lock.
Quote:
Originally Posted by glennsanders View Post
Just asking,why are they not made with a hole
The current stock replacement thermostats do have a vent hole with a "jiggle pin" in them to shut them off after the cooling system is filled and the engine is running.

Vent open for filling:



Vent closed when water pumping:



The Stant thermostats that I use and recommend have a notch in the valve plate that lets the air through when filling. It is visible in this photo of the Stant on the right. Left is the current stock replacement stat just showing the comparison of the openings in each for water to flow through - the Stant obviously bigger.

__________________
Prof. Henry (The Roaming Gnome)
"It is good to have an end to journey toward; but it is the journey that matters, in the end.” *Ursula K. Le Guin in The Left Hand of Darkness

Last edited by Old Henry; 08-26-2016 at 06:18 PM.
Old Henry is offline   Reply With Quote