Fan switch

I have a 200 on 185 off fan switch from summit. it is mounted in the thermostat housing the problem is its not turning my contour fans on until the temp is at 210-215. thats with a autometer electric gauge. it is the second switch i have tried,would mounting it in a different location make it work more accureatly? any ideas?
 
Alternate placement for a temp gauge sender: Use the heater feed that comes off the intake manifold. Cut the rubber hose that connects the manifold water feed to the heater and splice in a tee adapter for the temp gauge sender. Be sure to use the same water feed line as the ECT sensor. That way you will get the most accurate temp readings.

Tee adapter info:
Make a pilgrimage to your local hardware or home supply center and get some copper pipe and a tee that fits the temp gauge sender. Solder two pieces of copper pipe onto a copper pipe tee with threads in the tee part. Find the correct brass fitting to match the temp sender threads to the tee fitting.

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