How hot does this truck run

[Ciciro]

I drive a 1984 Nissan 720 4WD 4 cylinder 2.4 

 

I am experimenting with electric fans. 

 

This truck's heat gauge has always sat below the middle, i replaced the thermostat with an OEM 82°c thermostat and it improved a little. 

 

Today I used a laser thermometer to see the temp around the thermostat housing and it reported 145°F

 

The thermostat *should* be opening at 180f. I bought a thermo switch to activate the fans at 190°f and turn off at 175°

 

I can't really find what temp i should be running at. I assume it's 175° but this truck never runs this hot. 

 

During the experiment i used cheap Chinese fans and for te most part kept it cool, even with AC on. But during hotter days or excessive idling it did eventually overheat. It would creep up to the middle on the gauge, stay there for about ten mins then go up until I turned it off. The Chineseum fans are being replaced by very powerful SPAL fans.

 

Should it be at 180? 

 

Would I risk engine damage if I let the fans activate at 190?

 

What issues might be keeping this truck from it's correct temperature?

[datzenmike]

The thermosta begins to open at 180F or 82C and will run around 185. 180F is the correct thermostat for the 720.

 

 Not around the thermostat housing but right on it. Check another vehicle to confirm it's reading properly. 145F is WAY too low. Put the old thermostat in and see what it reads. Unlikely to have two bad thermostats stuck open. Generally Datsun Nissan temps read about 1/2 on the 'run range' of the gauge and a needle width above.

 

If really reading 145F the fans will never come on.

 

I have a 200sx thermo switch to turn the fans on at 192F. That's about 2/3 on the marked 'run range' on the temperature gauge.

[Ciciro]

The old thermostat ran even cooler.  I've replaced the thermostat over the years several times and it's always ran cool. In the winter I would sometimes covered the radiator to get it to warm up. I've rebuilt the engine and replaced alot of cooling components and its still a gremlin issue.

 

I tested the OEM thermostat in boiling water and thermometer and it opened exactly at 180, as it should, but the truck still runs cool, 

 

I guess my thermo switch should be fine then, that's a good start.

[Ciciro]

I checked them laser thermometer on a different vehicle, it showed the same temp as the ODB scanner reported so I know the thermometer is fairly accurate.

[datzenmike]

You shot the intake where the top radiator hose connects? Because if 145F the thermostat will never open and that is pretty much impossible.

 

Does the rad hose get hot to the touch???