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Tips
Tips

It works....with one caveat. Dang.

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Ok, so three choices. Take your pick :

1) Wire the solenoid in parallel with the relay coil. If there isn't already a diode on the relay or solenoid, add one, so no question of inductive kickback damaging the temp sensor. Easy, quick, this would be my choice (but I have diodes laying around so don't have to drive to Radio Shaft).

2) Add a relay for the solenoid, with it's coil in parallel with the existing relay. You could still add shunt diodes if you want, but the relay contacts should be big enough to deal with the solenoid without the diode.

3) Find a double pole relay and use it to replace the existing fan relay. This is the most elegant solution, but I don't know of an easy source for a double pole relay. The starter relay from a 74-75 TR6 is double pole, but I don't know if it's coil is rated for continous duty or not.
 
Ya know Bill, just stick the stock fan back on and call it good. :devilgrin:
 
Better than a tooth ache.

You can take an aspirin easily enough. Harder to drill and fill your own cavity.
 
TR6BILL said:
My Spal fan is controlled by a Spal relay, which is pretty much a standard relay. Hot in and hot out, with a ground and a tickler wire to the Spal temp sensor. I also set up a dead short wire to a switch on the dash to ground out the sensor to override manually. With indicator light. I wired the solenoid with a ground wire to the body and the hot wire to the same hot wire that feeds the fan, after the relay. Therein lies my problem. The little bit of juice fed back through this wire is enough to keep the solenoid open until there is zero juice coming in, ie, the fan is motionless.
Click to expand...

awright, I'm back. Couldn't get a keystroke in edgewise on the computer last night.

Bill, simple, take the wire that goes from the relay to your solenoid off the hot wire after the relay, and put it on the hot wire BEFORE the relay.
Then take the other wire from the solenoid and put it on the wire that goes from your temp sensor to your switch.
All will be well.
 
For some reason I am having and interesting time posting a picture. Dunno why.

I will get this figured out yet, the same way I always have, by pushing buttons until something significant happens.

I have a screen shot saved as a jpeg of a pdf file I scanned of a drawing I made of Bill's bumper upper wiring.

I am just having trouble getting it to display.
 
Adobe%20Reader%20-%20%5BDOC031009.pdf%5D%203102009%2081541%20AM.bmp.jpg


well, there it is, if anybody can make it big enough to see, be my guest.
 
TR3driver said:
<span style="font-weight: bold">Ok, so three choices. Take your pick :

1) Wire the solenoid in parallel with the relay coil. If there isn't already a diode on the relay or solenoid, add one, so no question of inductive kickback damaging the temp sensor. Easy, quick, this would be my choice (but I have diodes laying around so don't have to drive to Radio Shaft).
</span>
Click to expand...

Bill this is the simplest, best solution. Just hook the solenoid up directly to the thermostat or the COIL side of the relay and everything will work.
No need to worry about the temp sensor, they will handle way more current than what the solenoid will ever draw.
 
71MKIV said:
Adobe%20Reader%20-%20%5BDOC031009.pdf%5D%203102009%2081541%20AM.bmp.jpg


well, there it is, if anybody can make it big enough to see, be my guest.
Click to expand...


G_d bless you Steve. That said, I CANNOT READ YOUR DIAGRAM! I tried blowing it up and it all came out fuzzy, unreadable. And thanks everyone for the spirited help. I may sound like the Village Idiot, but can someone spell it out in kindergarten terminology for me? I will make a run Friday to the marine electrical shop for a good relay and some good wire. Got plenty of bullet connectors. Really, really want this to work. Hang with me. V.I.
 
Two wires from the solenoid, right? One goes to the hot wire to the relay; the other goes to the wire from the relay to the temp sensor and dash override switch.

Sorry, I have to run, or I'd redraw Steve's diagram for you.
 
I've currently got ONE good eye and a lot of angst and frustration. No way to diagram the circuit.

I like the two-in-one relay solution best.
 
Sorry Bill, I can't make it out enough to redraw it either. It's too small to blow up.
 
Mumble mumble, I'm at the wrong computer too. I'll be at the right one tomorrow morning. I'm going to try something. Bill, Watch for PM
 
Bill, I sent you the link to the actual drawing by pm. Did you get it?
 
Probably still cleaning up the eggs off the fridge
 
Got it Steve. Sitting on my work bench, waiting for Friday (my day off) when I can go to the marine electric store to get some good wire and shrink tubing.

On another approach, a buddy gave me a <span style="font-weight: bold">diode</span> (he has a towing service and drag races a Chevy II [made PINKS]). We ran it across a 12 volt field and it passed all the juice through one way and blocked all the juice the other way. Hmmmm. Just an inline setup. Confusing myself.
 
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