Trying to jump the hydrofan solenoid to get it running, but having no luck

rakkasan

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Mar 31, 2005
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there are two lines, yellow/blue & yellow/red, an if I read the wiring diagram correctly, the yellow/red is the 12v & the yellow/blue is the ground. I've tried to run a 12v lead from the battery to the yellow/red, but the solenoid isn't opening to turn the fan.

Being an electrical dummy, what am I doing wrong?
 
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JonoTurbo

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Mar 30, 2005
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Yellow/blue is positive, Yellow/Red is ground, you have them backwards. Also, from what I've seen, wiring the solenoid to 12v does work, but it causes the solenoid and the hydrofan system to overheat. Also I believe the hydrofan ecu only uses up to 5v to open the solenoid, which could be part of this problem.
 

rakkasan

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Mar 31, 2005
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ok, thanks Jono. I'm throwing a 2ohm, 25w resistor in it (Aarons recommendation), but I didn'y know it was a 5v lead, so thanks for the heads up.
 

rakkasan

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Mar 31, 2005
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JonoTurbo;1625710 said:
Yellow/blue is positive, Yellow/Red is ground, you have them backwards. Also, from what I've seen, wiring the solenoid to 12v does work, but it causes the solenoid and the hydrofan system to overheat. Also I believe the hydrofan ecu only uses up to 5v to open the solenoid, which could be part of this problem.

ok, tried putting 12v to the yellow/blue, no luck, the fan still free spins. Then I tried to ground the yellow/red to the neg battery terminal as well, thinking that since the hydrofan ecu wasn't in place, the circuit wasn't complete, still no luck. WTF? This is why I HATE wiring. The hydorfan solenoid should be wide open, but no its not. Any ideas?
 

mkiiichip

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Sep 10, 2007
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Just to be clear, you have the motor running right?
Also sometimes components that are designed for 5v, are junk if you put 12v to them. But it sounds like Jono Turbo has done it before without failure, so that may not be the case here.
 

rakkasan

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Mar 31, 2005
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mkiiichip;1625968 said:
Just to be clear, you have the motor running right?
Also sometimes components that are designed for 5v, are junk if you put 12v to them. But it sounds like Jono Turbo has done it before without failure, so that may not be the case here.

yeah, motor is/was running. I tried both a 5v & 12v lead, and nothing. I spoke to Aaron, and in the morning Im going to try shimming the solenoid with crush washers in order to mechanically open the valve. If that doesn't work, I will try to remove the solenoid all together and cap it to see if I can get it to engage.

Also, Jay is running a few test on a spare set up he has to see what he can get to work. Hopefully he & Ricky can get it to work on his end and relay the info to me, I dont feel like spending another $500 for a mechanical set up.
 

rakkasan

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Mar 31, 2005
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got it open, now all I have to do is determine the correct resistor to put in line to reduce it down to 2-3 volts, or maybe even a potentiometer under the hood.
 

rakkasan

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Mar 31, 2005
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I came up with a better solution last night after I thought about it last night. I'm going to shim the solenoid so it runs at about 30% all the time, then wire it into my ECU to open 100% at 190 degrees.
 

rakkasan

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Mar 31, 2005
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ok, I used a 22 Ohm resistor and it ran at about 30%, and a 15 Ohm resistor kicked up to about 50-60%. I ended up with a continuos (switched) supply from the 22 Ohm, and then the 30 Ohm line will be controlled by a cicuit set to temp on my Stinger ECU. Seems to be good set up. I'll write more later after a good bit of testing.