Temperature Probe
The temperature probe is installed in the radiator core next to the coolant return port (upper hose returning coolant from motor). This is per manufactures installation instructions. We’ll see how well it works and its long term dependability. If not acceptable will fit up a direct coolant contact probe.
(4/29/2006)

As I suspected the radiator temperature probe method is the deal breaker for this electric fan conversion. Installation per manufactures instructions results in several issues.

1) Low speed driving, 2 – 15 MPH or so, provides enough air flow to keep the probe cool and prevent the fans from turning on even though there is not enough air flow to keep the engine from over heating. On a ~70 degree day.

2) Moderate speed driving, 20 – 30 MPH, pulling the grade of an ordinary logging road, provides enough air flow to keep the probe cool and prevent the fans from turning on even though there is not enough air flow to keep the engine from over heating. On a ~70 degree day.

3) Coolant exiting the radiator and cooling the transmission fluid can exceed healthy temperature for the transmission before the fans are activated.
(6/29/2006)

Owner caption April 2006 · Photo 665 of 1021