Nashville TJ's Build - Continued

Not a problem at all, @JMT. It’s nice to get a bunch of posts to the thread - regardless of the subject.

I get it on the math. When I was doing my undergraduate work, I got to my last semester having met all the requirements for my major and a minor - I just needed about 15 credits to get to the 120 required to graduate. I could have coasted, but I always enjoyed economics - so in that last semester I took five upper level economics courses to pick up that degree as well. Upper level econ is heavy, heavy on the calculus side - but today I wouldn’t recognize a differential equation if it bit me in the ass.

But even building the rig, I still use trig, geometry and algebra all the time - so all that study was worth it.

Freshman year we were sitting outside our building and a friend walked up huffing and puffing “I hate my economics class.” I said oh yeah which one is it? She said “I dunno the one in supply and demand.” Well darlin’ that would make sense why you’re having trouble, as that is the foundation of economics.
 
I saw the email notification and thought I'd take it! But Brian had beat me too it. Just was staring at it and thought it looked different than mine
Well, you are in luck my friend. For some reason Brian no longer wants the thing - so it's on its way to you!
 
like the Wildman says kudos to you for offering what you thought it was for nothing. mistakes happen.
Well, I prolly would have just guilted Brian into paying for it. Just ask Victor @gasiorv. When we wheeled a few weeks ago I gave him a little bolt to secure his power steering pulley - and I made him pay for it with a gallon of antifreeze!!!

;)
 
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Well, I prolly would have just guilted Brian into paying for it. Just ask Victor @gasiorv. When we wheeled a few weeks ago I gave him a little bolt to secure his power steering pulley - and I made him pay for it with a gallon of antifreeze!!!

;)

That’s a good ol’ fashioned non taxable barter where I come from…
 
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Well, I prolly would have just guilted Brian into paying for it. Just ask Victor @gasiorv. When we wheeled a few weeks ago I gave him a little bolt to secure his power steering pulley - and I made him pay for it with a gallon of antifreeze!!!

;)
Red RTV when I got home and that bolt is staying, you can keep the antifreeze.
 
About 2 minutes after I completed wiring up the new fan and buttoning up all the panels a couple of weeks ago, I realized that I had forgotten to wire in the override for the A/C. Wonderful. So once again, I tore into my old friend the PDC...

Jeep - Spal Fan - 10-13-2021 (32).JPG


In the old setup, engaging the A/C triggered a relay in the PDC sending a ground to the fan relay (also in the PDC), which in turn triggered the fan. Since there is no fan relay in the new setup, I modified the A/C trigger relay to pass a 12V current directly to the fan controller. I added a 3amp fuse to the PDC to provide the power for the relay.

There is a single circuit on the Spal fan controller which overrides the temperature switch and engages the fan at full turbo-jet speed when you pass it 12 volts. Since I had already wired this circuit to the fan override switch on the dash, adding the A/C trigger relay to this circuit means that there are two 12v sources feeding the override circuit on the controller.

It worked perfectly. Turn the A/C on, and the fan spins up to full. Hit the override switch, and the fan spins up to full. And no problem at all if they are both engaged at the same time....
 
When I was testing the new configuration, I saw a minor issue - and you know how much those minor issues bother me...

There is an indicator light on the fan override switch which illuminates when you engage the switch. It's a quick visual reference when you have the fan override turned on. Here it is:

Jeep - Spal Fan - 10-13-2021 (35).JPG


Notice in this picture that the switch is in the off position - but the A/C is on and that is triggering the indicator light.

Yeah, a little thing but it bothered me. I want that light to tell me that the switch is engaged - but it was telling me when the fan was being overridden.

The way this switch works is that the light is located on the cold side of the switch. When you turn it on, and send current to the cold side of the switch and on to its destination, the light illuminates.

Since I connected the A/C override relay to this same circuit, when that relay triggered 12 volts also comes back down to this switch and lights the light.

To rectify the light issue (pun intended), I added a rectifier diode the circuit. A rectifier diode allows electricity to only flow in one direction. I had a box of these things in my electrical stuff. The trigger circuit I added was 3amps, and I had a 3amp / 400 volt rectifier diode in the kit.

Jeep - Spal Fan - 10-13-2021 (40).JPG


Then it was just a matter of pulling the dash apart (yet again), and adding in the rectifier to the outbound side of the override switch.

Jeep - Spal Fan - 10-13-2021 (47).JPG


And then covering it with heat shrink. The rectifier prevents the current from flowing back to the switch (and the light) when 12 volts hits the circuit from the A/C trigger relay.

Jeep - Spal Fan - 10-13-2021 (48).JPG


Now as I understand it, one consequence of using a rectifier diode is that they generate heat - especially as they approach the rated capacity. This circuit is drawing way less than 1 amp, so I don't think heat is going to be an issue.

But, if you are ever wheelin' with me and suddenly the rig bursts into flames - you will know why...

Anyway, it worked. Now the light comes on only when I hit the switch. Once again I can sleep at night (yeah, I've got problems...
tango_face_smile.png
).
 
your lucky your at a point you can make time to chase what's just bothersome to you.

been kickin around the idea of a front axle,
as much as a 14B up front would be a beast it's just to big for our platform above the centerline of the axle tubes more than under center that can be shaved away.
the ford axle is just a PITA, cheap but lots of work to make it right.

so it's lookin like a Dana 60. Fusion 4x4 and ECGS both offer HP housings for just under 2k.
can't find if Currie sells builder axles but i like that rolled center. do you know?
 
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your lucky your at a point you can make time to chase what's just bothersome to you.

been kickin around the idea of a front axle,
as much as a 14B up front would be a beast it's just to big for our platform above the centerline of the axle tubes more than under center that can be shaved away.
the ford axle is just a PITA, cheap but lots of work to make it right.

so it's lookin like a Dana 60. Fusion 4x4 and ECGS both offer HP housings for just under 2k.
can't find if Currie sells builder axles but i like that rolled center. do you know?
No idea on the Currie question, but let me know if you find something. I'm still kicking around ideas for a front rebuild on mine as well.