I apologize for starting yet another thread on cooling, but a quick search hasn't found anything specifically on this topic.
Stock coolant piping has hot engine coolant entering the bottom of the radiator and exiting from the radiator top hose.
I am installing a double pass Ron Davis radiator into 2511. Supplied by Dennis Q, the inlet tank has two threaded bosses for temperature sensors. There are no threaded bosses in the outlet tank. See photo.
In talks with Jon Haas regarding his EIS engine control box, he told me he strongly believes the fan temperature sensor should be sampling at the outlet instead of the inlet.
To do this would require the addition of a threaded boss on the outlet tank or the use of an in-line temperature sensor housing spliced into the coolant return line. Either approach is fairly easy to create, but I would lean to adding the threaded boss instead of adding two more hose clamp areas on the coolant piping.
Ron Davis offers two sensors, one turns on at 185° and off at 165°. The other turns on at 195° and turns off at 175°. There are aftermarket sensors with different ratings, one I have seen turns on at 200° and turns off at 185°.
QUESTION "A" -
Is the inlet or outlet tank the best place for a fan temperature sensor?
Could they both be acceptable if fitted with the "correctly" rated temperature sensor?
QUESTION "B" -
What sensor rating should be used if installed in the inlet tank?
Conversely, what sensor rating should be used in the outlet tank?
QUESTION "C" -
Engine thermostats are readily available in 160°, 185° and 195°. Is the thermostat temperature rating dependent on the fan sensor rating?
I am leaning to installing:
180° engine thermostat
195° fan temperature sensor in outlet tank
Please share your comments, wisdom and suggestions.
Larry
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