EA81 to EJ Radiator & Hoses & temperature sending unit

[Responsible Jon]

I went the route of having the EJ sized necks brazed onto my stock EA81 radiator for my Brat conversion.  The donor motor is from a 95 Legacy, and the stock legacy hoses fit perfect with just a little trimming from either end to compensate for the radiator being closer and not as wide as what they were designed for.  I was very worried about this step, but I'm pretty pumped, it looks like it has really come together.  My fan shroud and electric fans seems to fit the space nicely and I hope it will keep everything cool, I would like to come back around and install the AC, but I'll just get it running first.  

Hopefully someone can help me out with this question.  The sending unit / sensor that is in the passenger side of the stock EA81 radiator, I think was to trigger the stock fan relays, which now should be controlled by the ECU.  Could I connect this to my stock temperature gauge to get a correct reading?  Or is there some other place the temperature was measured on the stock EA81?

 

[Responsible Jon]

Here is a picture of the shroud I built to mount the fans and force them to pull the air through the radiator instead of just stirring the air around. 

[el_freddo]

EA temp sender unit is in the intake manifold just under the thermostat. 

Two things you can do: 

1) fit the EA temp sender unit to the EJ coolant crossover pipe - might need to have a plate welded on to allow appropriate thickness to seal properly. 

2) plumb into the heater hoses (the one coming from the coolant crossover pipe) in a metal T piece that’s got a wire to an earth point. 

Both are effective. T piece is easier when it comes to engine swaps etc. 

or you can fit a mechanical/electric aftermarket gauge for ultimate definitive temp reading. Same trick with the T piece. Mechanical doesn’t need an earth wire. 

Your shroud looks good. I presume the fans fit around everything on the front of the EJ?

Cheers 

Bennie

[el_freddo]

PS - that unit in the side of the radiator is only a temperature switch. It’ll do diddly squat for your gauge reading until it “turns on”, then your gauge will go sky high. 

Cheers 

Bennie

[Responsible Jon]

Bennie,

Thanks for clarifying, I thought it might be the case rather than a variable reading that it was more of an on/off switch. I’ll try measuring the resistance needed to properly run the EJ sending unit to control my gauge as I found in This thread.  The fans fit snug but with clearance all around, I’m happy with how it turned out. The two smaller fans were chosen to use space around the crank pulley as much as possible, and it all drops in without a fight or squeeze. With the desire to install AC and keep my cyclops light there just isn’t much room for pusher fans. 
 

 

[Numbchux]

Yea, the EA sending unit uses larger thread than the EJ, so can't just use it.

I just wired the EJ sensor to the EA gauge, it reads low, but still useable. Or you can use a resistor to change the signal, pretty sure the information is in my write-up.