I'm just coming into that junk w/ my MSII. Both the WP, and cooling fan are controlled similarly the same way as yours except my ECU provides a very low amperage 12v signal that acts as the trigger for the relay.
Build Thread Want To Blow 5 Years And $50k On A Foxbody? Step By Step Instructions Inside!
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I'm just coming into that junk w/ my MSII. Both the WP, and cooling fan are controlled similarly the same way as yours except my ECU provides a very low amperage 12v signal that acts as the trigger for the relay.
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Yup. I could do a positive trigger too. A negative trigger was easier for me from a wiring standpoint. It's a little simpler to wire in an override switch that way.
All of this stereo stuff is boring................lets get back to the nuts and bolts of making HP! damn it! BTW, On my build, I made all of the switches that turn on one thing or another, a negative switched toggle. Everything has power to it and the switch provides the ground, much like the ECU provides the ground for the fuel injectors.
THIS is what i need, fan keeps pulling enough amps on a warm start that it makes the battery weak enogh to well the solenoid contacts
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It's a nice feature to have.
I ran into an issue with the fan today. I started the engine up and the fan came on and stayed on. It wouldn't shut off, even with the ignition off. I had to disconnect the battery to shut it off. I unplugged the fan, reconnected the battery and confirmed 12v at the terminals from the relay. My guess is that the relay terminals welded themselves together. @jrichker, could having a worn out fan motor cause enough resistance to make the locked rotor current high enough to fry the 75A relay? The Taurus fan does spike to 100A for microseconds, but is supposed to have a locked rotor current of around 60A and a running current of 33A when wired for high speed. I haven't heard of people having issues with this fan and relay combination, so an old motor is the only thing I can think of.
In the meantime, I'm going to replace the relay with another one and then wire the fan for low speed. Not sure if it will keep the engine cool enough at idle, but I'll give it a try.
I ran into an issue with the fan today. I started the engine up and the fan came on and stayed on. It wouldn't shut off, even with the ignition off. I had to disconnect the battery to shut it off. I unplugged the fan, reconnected the battery and confirmed 12v at the terminals from the relay. My guess is that the relay terminals welded themselves together. @jrichker, could having a worn out fan motor cause enough resistance to make the locked rotor current high enough to fry the 75A relay? The Taurus fan does spike to 100A for microseconds, but is supposed to have a locked rotor current of around 60A and a running current of 33A when wired for high speed. I haven't heard of people having issues with this fan and relay combination, so an old motor is the only thing I can think of.
In the meantime, I'm going to replace the relay with another one and then wire the fan for low speed. Not sure if it will keep the engine cool enough at idle, but I'll give it a try.
So, my hypothesis of the relay being stuck closed was somewhat right and wrong. When I was unbolting it, I heard it click. After I got it out, I checked it's operation with a battery and it's working fine. It's not welded shut.
I still put the a new relay in and wired the fan for low speed. I did notice that the relay would click very quickly when I turned on the ignition. The ECU must be momentarily activating the outputs when it turns on and is initializing everything. That's my only guess. It only did it a few times when I cycled the ignition. Now the relay does not click when I turn on the ignition. I tested the fan through the ECU and it's operating correctly. I'll have to keep an eye on things to make sure it keeps working properly.
I still put the a new relay in and wired the fan for low speed. I did notice that the relay would click very quickly when I turned on the ignition. The ECU must be momentarily activating the outputs when it turns on and is initializing everything. That's my only guess. It only did it a few times when I cycled the ignition. Now the relay does not click when I turn on the ignition. I tested the fan through the ECU and it's operating correctly. I'll have to keep an eye on things to make sure it keeps working properly.
Work and other projects have been consuming me a bit lately.
Last time I started the car and drove it around a bit, the coolant was boiling when I shut the engine down. I suspected the radiator cap want bad. I bought a replacement 16 psi cap, but haven't had time to run the car again. I hope the cap was the issue. There's no signs of head gasket problems.
I also need to adjust the clutch a little. It's catching a bit too high.
Last time I started the car and drove it around a bit, the coolant was boiling when I shut the engine down. I suspected the radiator cap want bad. I bought a replacement 16 psi cap, but haven't had time to run the car again. I hope the cap was the issue. There's no signs of head gasket problems.
I also need to adjust the clutch a little. It's catching a bit too high.
Let me be the first to say that I appreciate the update even when there is little to say. (That means I'm not the only one)
'Cept even when there is little to say, I still say alot.
Still trying to source what I hope is a valve cover leak at the back of the head, I currently have a rag tied around the back lip of the valve cover hoping that the damn drip that shows up after running the engine is coming from there, instead of the head gasket.
As for engine coolant,I have an exact opposite problem going on.
I can't run the water pump continously. The stupid temp plummets from 180 to about 160 if I do, and never gets back there if I leave it on. I'm thinking the heater control valve is open, and allowing water to bypass the t stat.
'Cept even when there is little to say, I still say alot.
Still trying to source what I hope is a valve cover leak at the back of the head, I currently have a rag tied around the back lip of the valve cover hoping that the damn drip that shows up after running the engine is coming from there, instead of the head gasket.
As for engine coolant,I have an exact opposite problem going on.
I can't run the water pump continously. The stupid temp plummets from 180 to about 160 if I do, and never gets back there if I leave it on. I'm thinking the heater control valve is open, and allowing water to bypass the t stat.
Does the MS have the ability to turn the water pump on and off at certain temperatures? If you can program a hysteresis into it, that would be ideal.
Yeah it does, and I'll do that if I have to,...just seems crazy that the engine won't stay hot when the pump is running. I have a manual switch wired in to override the W/P control coming from the MS, and right now I'll let the tem get to 190 and then turn on the pump. It'll start coming down so fast from there if i don't shut the pump off at 175,...it'll continue down to about 160 and the stupid ECU goes back into WUE mode.
Crazy that I gotta use the ECU to act like a T-stat. The engine is partially filled, and half of the water passages to the head are blocked off, you'd think it would boil it's balls off for christsakes
Hmmmm.....it does have a 35GPM electric W/P split to 3 -12's....probably never was intended to move as much water as it is now passing.
That's with no hood, fenders, or front end while parked inside a garage, right? Put the car out in the summer heat with everything buttoned up and you'll probably see things heating up a little easier.
I did start the car up last night and let it idle for a while. Water pump comes on at 150 degrees. The fan kicks on High speed at 190 and then turns off at 180. With the hood closed, radio on, headlights and fog lights on it took about 5-6 minutes for it to come back down to 180 before the fan turned off. The Taurus fan really does put a heck of a load on the electrical system. Voltage would come down to 13v while the fan was running. Everything seemed to work well though. No boiling coolant after shutdown either. Progress...
I was previously running a dccontrol unit, but now the fan is controlled by the ecu via a 75A relay. The lights don't dim when it kicks on, but it does pull the voltage down some when running.
Car is scheduled to be on the rollers again July 28th. I'll spend the next 2 weeks checking everything over to make sure she's ready to roll.
Mine does that too. It blips on and off very fast. I read it's because the ecu initializes all the inputs and outputs when they key is turned on so it applies the ground or 12v for milliseconds.
It has been quite a while, actually. I probably won't have any new pictures until dyno day. There will be some professional rolling shots soon after that also.
Just Saying it's been awhile since any pics.. Lol
