2017 FUSO FG engine cooling fan problem

#1
Apparently FUSO in 2017 started using an electrically operated engine fan in place of a viscous fan. My dealer said it was to reduce engine load and increase milage. This may be a good idea except my fan engages much to much. On a recent trip it would engage for 20 to 40 sec. every 1 1/2 to 2 minutes while traveling on a level road with an outside temperature of 76 deg. F and an engine temperature that was normal. Is anyone else having this problem or does my FG have a temperature sensing or ECU problem?
 
#2
Hi Gary, My truck is plated early 2016 and I'm pretty sure my cooling fan is electrically operated (although I've never looked I think it acts that way). On long highway trips I hear it cut in now and then, sometimes when working hard up a hill. I've been in pretty hot climates and it all seems to work as intended. It doesn't cut in anywhere near as regularly as what you have reported. It may be that your temperature sensor is a bit crook?

Karl
 

Bris31

Adventurer
#5
.... outside temperature of 76 deg. F and an engine temperature that was normal
Were you checking engine temperature from stock gauge or from after market one?
Reason, for the last 20-30 years stock gauges are made with dead zone, as I was reading of about 20 degree C difference. That means engine temperature may be higher than normal but the needle will stay in the middle.

I have 94 Toyota Surf with both viscous & electric fans. Electric fan will always work when aircon is switched on. Otherwise only sometime while cruising but definitely at a traffic stop on hot days. My mechanic told me electric fans also work as a helper when engine temp goes above normal and viscous fan can't cope. By the way I did some mod on stock temp gauge electronic circuit and now the needle will go up/down as it responds to engine temperature - like in old days before dead zone engineering.
 
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#6
Engine Temp.

I have been checking the engine temperature using the stock gage. I assumed [maybe in error] that the gage worked correctly. Its hard to believe that the engine needs additional cooling while traveling on a level road with a mild outside temperature. Viscous fans that I am familiar with turn at about 20% of shaft speed even when disengaged and this electric fan has no resistance when disengaged. Maybe that 20% is enough to keep the engine temp. in a normal range. I hope that is not the case because when the fan engages its so loud you can't carry on a conversation let alone listen to the radio. Maybe that is why the radio is an option, because you can't hear it anyway.


Gary