I installed my Stewart warner coolant temp sensor in the place where the radiator fan thermoswitch usally goes and it only goes up to about 120 degrees or so when the engine it warmed up..

On my AEM EMS the coolant temps are showing 180-200 degrees.. Also the lower radiator hose is cold but the top one is hot.. The engine doesnt overheat at all so what could this be?

 

The fan switch is positioned to be more sensitive to the coolant coming back from the radiator. You're just measuring at a point where the hot water from the head, & the cooler water from the radiator, haven't mixed completely.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JimBlake &raquo;</TD></TR><TR><TD CLASS="quote">The fan switch is positioned to be more sensitive to the coolant coming back from the radiator. You're just measuring at a point where the hot water from the head, & the cooler water from the radiator, haven't mixed completely.
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So is this a good place to have the sensor.. Also if I run the car longer will the temp reading then be correct once all the coolant has mixed?

 

Yeah, I guess my answer doesn't really HELP...

Seems to me it's not a good place for the measurement. But I don't know where else to suggest, or where most people put that sender. What about removing the temperature gauge sender & putting it there?

The mixing I'm talking about isn't going to get better by running the car longer. The 'cold' stream from the radiator is always gonna be colder than the fluid recirculating from the head. You have to find a different location, farther downstream from the point where this mixing is happening.

If I was designing the engine, I'd put another fitting in the head, next to the ECT sensor. You'd use that for a guage sender. Then I'd get fired for making the engine cost $5 extra.