Tweet
Thermostat Housing Roof Too Low???
Don,
You wrote that “A normal thermostat will move approximately 3/8" between fully closed and fully open.”
I have purchased the new thermostat housing with the shoulder nuts, gaskets and what I assume is a Volvo-type thermostat. I like to see how things work, so I put the thermostat in water and used a calibrated digital thermometer to measure the opening, fully open, and closing temps. The thermostat works well opening at 140 degrees, fully open at 163 degrees, and closing fully at 140 during cooling.
An unexpected observation was that the thermostat opens quite a bit farther than 3/8”. In fact, it opens about 3mm farther than the clearance that the housing provides below the water pump inlet.
This means that when the engine heats up to a bit less than 163 degrees; the thermostat will act like a "Y" valve and positively close off the water pump inlet forcing every bit of the cooling water through the water jacket.
I think that’s good engineering but; (and this is my question) does it hurt the thermostat to be compressed in this way?
I noticed that the underside of the water pump inlet has been machined. So, I’m guessing that you’ve already taken all of this into account. Let me know if I’m just being a curious cat or if this bit of internal machining needs to be told to those who might consider drilling their own thermostat housing without machining the inside of the WP inlet. Thanks.
You wrote that “A normal thermostat will move approximately 3/8" between fully closed and fully open.”
I have purchased the new thermostat housing with the shoulder nuts, gaskets and what I assume is a Volvo-type thermostat. I like to see how things work, so I put the thermostat in water and used a calibrated digital thermometer to measure the opening, fully open, and closing temps. The thermostat works well opening at 140 degrees, fully open at 163 degrees, and closing fully at 140 during cooling.
An unexpected observation was that the thermostat opens quite a bit farther than 3/8”. In fact, it opens about 3mm farther than the clearance that the housing provides below the water pump inlet.
This means that when the engine heats up to a bit less than 163 degrees; the thermostat will act like a "Y" valve and positively close off the water pump inlet forcing every bit of the cooling water through the water jacket.
I think that’s good engineering but; (and this is my question) does it hurt the thermostat to be compressed in this way?
I noticed that the underside of the water pump inlet has been machined. So, I’m guessing that you’ve already taken all of this into account. Let me know if I’m just being a curious cat or if this bit of internal machining needs to be told to those who might consider drilling their own thermostat housing without machining the inside of the WP inlet. Thanks.