Hydraulic FAN

[guyed]

We use the original Hydraulic fan for cooling water radiator.

The trouble is - It works constantly, all the time when the engine is running.



Is someone having documentation for this?



Or



What make the fan works all the time?

Where we can control the operating method?



Please help



Thanks



Guy

 

[madmont]

My vehicle came with hydraulic fan and had a separate computer to control it

 

[guyed]

Dear Madmont, What Vehicle do you have?
what is the part number of the fan computer?

 

[Peewee]

Yeah, if it like the older 1uz (early 90's) then it uses a seperate ECU for the hydraulic fan.

The main ECU has no idea of its existance (they don't talk to each other).

All it does is turn on a solanoid when the temp reaches a certain degrees.

You can switch this solanoid with your own circuit though.
Either by a switch on the dash or with a temp sensor.

 

[madmont]

my donor vehicle was a Crown Majesta uzs141 1991 . The fan computer took signals from the ecu and temp sensor in the radiator and probably the air conditioning computer. There are many variations of the 1uzfe depending on which part of the world the vehicle was built for. I currently use a temperature switch to control my electric fan along with a microswitch to turn it off when doing more than 40kph.

 

[sideshow]

yes the fan ecu uses temp sensor in radiator and also signals from the air con
system to determine speed of the hydraulic fan

 

[guyed]

Our vehicle is UCF 20' 1997. there is no fan ECU. the Ecu is Toyota 89661-50240 where are the inputs? what turn the fan on /off??

Thanks!
Guy

 

[madmont]

It would probably be easier to make up your own control system for the fan as I did rather than try to make it work off the ecu.

 

[Cobra]

Madmont

What triggers your microswitch to switch on and off?

 

[madmont]

It is very sophisticated . I soldered a flat piece of metal to the arm of the microswitch and mounted it in the airflow behind the grill and when the wind blows on it it operates the switch. I wired it in series with the temperature switch. In time it will probably be affected by water but I figure I can replace it at little cost.

 

[Zuffen]

Another option is to use a "Hobbs" switch set at about 1psi.

This will turn off the fans when the vehicle is moving at more than a few k's an hour.

 

[SC400TT]

Where do I find this Hobbs Switch?

Ryan

 

[guyed]

The fan speed is variable or constant?
if yes, what controls the fan speed?

Guy

 

[sideshow]

just get a thermo switch to trigger a relay tpo turn on hydraulic fan solenoid

its just like any other thermo fan