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Topic: engine thermostat... (Read 421 times) previous topic - next topic

engine thermostat...

... how does it work?

I am well acquainted with the usual car type.  The bulb reacts to heat, offsets the tension from the spring, and opens the diaphragm.

My M11 thermostat has no diaphragm - it is open!  Old one, new one, photos on the web.

How does it control flow?

Matt B

Re: engine thermostat...

Reply #1 –
When I changed mine I had the same question. The coolant doesn't go through the center as most thermostats do. The outer rim
moves out to block the coolant. If you put the thermostat in a can with water and heat it up you will see how it works.

Re: engine thermostat...

Reply #2 –
So...

The clear flow straight through the thermostat is the bypass, and is limited by the restrictor in the 1 5/8" hose.  When the thermostat opens, is allows flow through the SIDE - the pipe that leads to the radiator!

Is that right?  I am learning stuff!

Re: engine thermostat...

Reply #3 –
Yeah that puzzled me too. Only figured it out after I put it in a pan of water and brought to a boil.

see ya
ken