Plain Jane OEM nothing to see here rebuild

[RETed]

I just want to comment on the current draw #'s...

Holy soda crackers Batman!
Trying to find a 75A+ relay is encroaching on the realm of "soleniods."
It's going to be difficult to find a quality relay rated that high from most common electronics parts vendors.
If you do find one, I'd bet it'll be pretty expensive too?

I was looking around for a 50A rated relay recently, and I ended up with an NTE one (Made in China) for about $10.

34A of current is a lot of juice for a single fan.
I'm sure there's other, aftermarket fans that'll run almost the same airflow for less current - i.e. more efficient.
We're talking minimum wire thickness at least 10AWG...8AWG?
Of course, you can't beat the price of a used fan...
But it looks at this point that the fan is faulty, so gambling with used equipment comes into play now.


-Ted

[JustJeff]

Originally Posted by Pete_89T2

Found this Taurus e-fan wiring diagram with a little googling on a DSM forum



If this diagram is correct, the fan body provides the ground (-) return, and there are 2 other wires - a high & low speed (+). Here it's rigged up so that whenever the switched +12V is on, and the "temp probe switch" is closed, the fan runs at low speed, and when the "AC Clutch wire" is providing +12V, that 2nd relay switches the fan to high speed. Note also they mention the high current draw when the fan starts up on high, and they recommend using a 75A relay, and the fuse to the battery is a 50-70A, and "normal" current draw on high speed is ~34A! Sounds like an alternator upgrade will be in order if you still have a stock FC alternator in there.

I've got a modded S5 alt (140amps). Looks like the diagram you provided works off of one temp switch, but both high and low are wired into the diagram.

I'm content using either high or low. I don't really want to mess around with finding a location for a second temp switch. Is the diagram I was using ok, provided I have correct wires for ground, low+, and high+?

Originally Posted by RETed

I just want to comment on the current draw #'s...

Holy soda crackers Batman!
Trying to find a 75A+ relay is encroaching on the realm of "soleniods."
It's going to be difficult to find a quality relay rated that high from most common electronics parts vendors.
If you do find one, I'd bet it'll be pretty expensive too?

I was looking around for a 50A rated relay recently, and I ended up with an NTE one (Made in China) for about $10.

34A of current is a lot of juice for a single fan.
I'm sure there's other, aftermarket fans that'll run almost the same airflow for less current - i.e. more efficient.
We're talking minimum wire thickness at least 10AWG...8AWG?
Of course, you can't beat the price of a used fan...
But it looks at this point that the fan is faulty, so gambling with used equipment comes into play now.


-Ted

I had the same problem finding a 50A relay. No one in town has one... I'm using a 40A relay now..which I thought would be ok. I got annoyed and put 10AWG wiring all around for the fan, relay, manual switch.

I don't know that the fan is faulty. I was playing around with both my fans today (mounted and spare). They both behave the same way. They both pull air on low and push air on high. That leads me to believe that the problem is not the fans...but user error instead.

[Pete_89T2]

Originally Posted by JustJeff

I've got a modded S5 alt (140amps). Looks like the diagram you provided works off of one temp switch, but both high and low are wired into the diagram.

I'm content using either high or low. I don't really want to mess around with finding a location for a second temp switch. Is the diagram I was using ok, provided I have correct wires for ground, low+, and high+?

If you're content to run at one speed, the wiring diagram you have should work, provided you find the correct ground wire. BTW, where did you get your S5 alternator modded to crank out 140A? Who does this and what does it cost?

Originally Posted by JustJeff

I had the same problem finding a 50A relay. No one in town has one... I'm using a 40A relay now..which I thought would be ok. I got annoyed and put 10AWG wiring all around for the fan, relay, manual switch.

I don't know that the fan is faulty. I was playing around with both my fans today (mounted and spare). They both behave the same way. They both pull air on low and push air on high. That leads me to believe that the problem is not the fans...but user error instead.

Yup, I'm pretty sure you've got your ground wire mixed up with one of the high or low speed + terminals.

[JustJeff]

Originally Posted by Pete_89T2

If you're content to run at one speed, the wiring diagram you have should work, provided you find the correct ground wire. BTW, where did you get your S5 alternator modded to crank out 140A? Who does this and what does it cost?




Yup, I'm pretty sure you've got your ground wire mixed up with one of the high or low speed + terminals.

I'm content with it that way for now. Once I've worked all the bugs out and am driving my rebuild regularly and reliably (ie: have worked out my fan issue and running hot issue) I'll go back and add features.

I got the alt off of ebay
http://www.ebay.com/itm/1990-Mazda-R...341811&vxp=mtr

One year warranty on their work and so far I've only had typical modded alt issues. There is talk about this over on the evil forum, but here is my best explanation of it. Because the alt is wound with higher gauge wire it needs to spin faster to reach 14v and recharging. So at idle it does not charge at 14v. As soon as idle hits even 1k it jumps up to 14v. So sitting at a light your battery is draining. Add a big drain like this monster efan and it does make me nervous. BUT I prefer this to not being able to fit a Taurus alt or even an FD alt under my TMIC.

And yes, my wiring was screwed up. I had ground going to fused constant. I have everything put back together and am about to take it around the block a few times and see if I throw the circuit breaker.

As a sidenote, the 3 pin wiring is very odd on this fan. I spent far too much time playing with the wires and a spare battery and seeing what the different combinations of wires did to my spare fan. Some combinations of wires using the low pin did create the correct direction (pull), but it didn't seem as strong as the correct low. I'm hoping that my faulty wiring is the cause of my overheating and blowing fuses. I will take a drive in summer heat and be in good shape....we shall see.

Well, it's not exactly conclusive...but temps drop like they should. I got temps up to 200ish going around the block. Once it was up to 190ish I brought it home and popped the hood. Used my temp gun cause I want to see when the fan switch is activating. Fan triggers on at 200. It turns off at around 185-190. Once I had the fan running and temps up to 200 I took it back out for a drive. The circuit never tripped (that I noticed). Temps dropped and it turned off. I was only driving around the block (had to leave for family dinner at my sister's). So I couldn't really drive it and test it. BUT I turned the fan home for the rest of the drive back to the garage and it the circuit never tripped. The whole trip temps never got about 205ish.....hopefully I have found my fix.