Writeup: Replacing the Mechanical Fan w. another OEM Aux Fan

[besthaticouldo]

this is a good write up...

 

[Fastdemise]

It's a probe that you put through your radiator as close to the inlet as possible. I've got a ton of pics and stuff from when I did it. I'll make a write up about it once my feet are back on solid ground (Navy underway) I left my digital camera in my armrest ^_^ But doing a electric fan conversion is totally worth the time.

 

[XJ-PRO]

Is this a stock aux fan? if not what is it??
Looks pretty free there!!

Thanks.-

After getting everything up and going, I don't think it will work with the FAL unit so easily. There's a single output, and about all I could manage without a great deal of work, is tying a relay to the outputs, and using that to switch a low amp circuit for a regular LED or lamp. That's one thing about the SPAL and DC units that eclipses the FAL. But, it works, and I've found a second leak, so fixing the system are going to take priority to further upgrading the system.

Here's the new setup.

Would have liked to use the shroud, but it wasn't going to work without a lot of trimming, and I had to have it together and running tonight. Project for another day, along with damming off the part of the fan that extends past the radiator. Project for another day #17.

Oh, and those buttonheads greatly improved the clearance. The picture sucks, but I'm not the least bit concerned about the pully and fan contacting, short of a wreck, and I'm going to try to avoid getting in one. Thanks, Don.

 

[Fastdemise]

Blowing off the dust:
I have a SPAL controller and wondering how people spliced it to the stock temp controller?? I have a 2001 XJ and not having luck finding the 2nd temp sensor since the SPAL controller uses a single wire sensor and the stock sensor up front is a 2 wire sensor. *shrug* Am I just dumb in my wiring???

 

[comanche91]

Blowing off the dust:
I have a SPAL controller and wondering how people spliced it to the stock temp controller?? I have a 2001 XJ and not having luck finding the 2nd temp sensor since the SPAL controller uses a single wire sensor and the stock sensor up front is a 2 wire sensor. *shrug* Am I just dumb in my wiring???

Yes, the 01 head does not have the single wire temp sensor in the back of the head used for the temp gauge. Assume you are thinking of using the 2-wire sensor in the thermostat housing? One wire is the sensor signal output; the other is ground (should be a black wire). You want to tap into the signal wire to provide the varying temp voltages to the SPAL controller. The voltage from this sensor (it feeds the PCM) however does not supply enough difference in voltage between the LO temp vs. HI temp sensor outputs that the SPAL needs for precise fan speed control. I tried it. It works, but the fan is somewhat spastic.

A better solution is to drill and tap a hole on the boss at the back of the head where the temp gauge sensor resides on the earlier OBDI models and use a stock temp sensor for the SPAL input. It uses 1/8" NPT.

 

[ehall]

Rather than drilling the head, you can drill a hole in the flat spot in the thermostat housing. In addition the block drain plug below the exhaust manifold is already tapped for 1/8 NPT, just have to pull the drain plug.

 

[comanche91]

Rather than drilling the head, you can drill a hole in the flat spot in the thermostat housing. In addition the block drain plug below the exhaust manifold is already tapped for 1/8 NPT, just have to pull the drain plug.

Good point(s). But isn't the flat spot in the stat housing already occupied by the PCM temp sensor? It's an 01 so I'm not sure.

 

[ehall]

There is a small flat spot on the front, right next to the center bolt

 

[lilnapsak]

how is this working out for you? im getting ready to do the same thing, but elimitating the AC and fan pully and relocating the alt up high

 

[comanche91]

Still have the same setup and controller. Zero problems after all these years.