Cooling Fan Tech

[AgitatedPancake]

i just did the volvo relay (thanks bebop) with taurus fan and i am not sure how it could improve. i mean that trip out my fan ran in low everybit of 75% of the time. now if it could act like a dimmer switch that would be cool. and maybe that what it can do.

They are not really sized great for the sheer size of a WJ radiator, and I can get my DD hot on demand unfortunately. I do believe part of the issue is the size of the transmission cooler I run, but I want to have my cake and eat it too

I took this video a while back for my fan controller testing, but it shows the max fan speed pretty well

 

[chaplinfj60]

I've bench tested the fan and it's absolutely insane. But I also decided it was a good (terrible) idea to build a custom fan controller for it at the same time, and that has taken way longer than expected...as expected haha. I should have that wrapped up in the next month or so though, and then can give a fair comparison to the Volvo (Taurus) fan that is currently in the jeep

i just did the volvo relay (thanks bebop) with taurus fan and i am not sure how it could improve. i mean that trip out my fan ran in low everybit of 75% of the time. now if it could act like a dimmer switch that would be cool. and maybe that what it can do.

They are not really sized great for the sheer size of a WJ radiator, and I can get my DD hot on demand unfortunately. I do believe part of the issue is the size of the transmission cooler I run, but I want to have my cake and eat it too

I took this video a while back for my fan controller testing, but it shows the max fan speed pretty well

that thing want to take flight. omg......

 

[Rockwood]

I've bench tested the fan and it's absolutely insane. But I also decided it was a good (terrible) idea to build a custom fan controller for it at the same time, and that has taken way longer than expected...as expected haha. I should have that wrapped up in the next month or so though, and then can give a fair comparison to the Volvo (Taurus) fan that is currently in the jeep

Ah, yeah. Saw that thread, then saw this:

VARIABLE PWM FAN CONTROL works with ANY sensor, compare to Lingenfelter VSFM-002 | eBay

It also has special selections for driving Solid State Relays (SSR's) to vary DC fans with no fuss. Easy 2-button programming makes setting the temperature span a snap, just run the engine and press one button at your "turn on" setpoint, another button at your "full speed" setpoint.

www.ebay.com

And yeah. Fuck it. For $65, why not?

i just did the volvo relay (thanks bebop) with taurus fan and i am not sure how it could improve. i mean that trip out my fan ran in low everybit of 75% of the time. now if it could act like a dimmer switch that would be cool. and maybe that what it can do.

Same fan/relay combo here. Keeps my XJ with stock radiator mostly cool (long grades will get warm though. LS swapping it this fall (with a much bigger radiator), so figured I’m gonna need moar fan.

 

[chaplinfj60]

my fan is 26x19 5.3 and taurs fan, no highways just trailer queen.

 

[AgitatedPancake]

Ah, yeah. Saw that thread, then saw this:

VARIABLE PWM FAN CONTROL works with ANY sensor, compare to Lingenfelter VSFM-002 | eBay

It also has special selections for driving Solid State Relays (SSR's) to vary DC fans with no fuss. Easy 2-button programming makes setting the temperature span a snap, just run the engine and press one button at your "turn on" setpoint, another button at your "full speed" setpoint.

www.ebay.com

And yeah. Fuck it. For $65, why not?

I've seen that one too, it seems like a great option for reasonable people

 

[Rockwood]

I've seen that one too, it seems like a great option for reasonable people

What connector does that fan use?

 

[AgitatedPancake]

What connector does that fan use?

I need to double check the part numbers, but I'm pretty sure it's the same as this SPAL unit. This isn't the exact link I ordered, but looks the same. The kit that I got came with grommets and terminals for a couple different wire sizes

GENUINE NEW Replacement Connectors, Terminals and Seals for Spal Kit 30130628 Brushless Fans - Walmart.com

 

[pvkj454]

I just wanted to give a shoutout to this post that slipped through the cracks a bit earlier on. After seeing it again and doing more searching I found more of your posts about this fan and what you were doing.

It looks like JLs and JTs have both 600w and 850w options along the line (392 getting a big fan makes sense, and maybe the JT for the tow rating). I got an 850w, It's a sweet fan. around 19" outside the fins, and the shroud is a nice versatile 20.5 x 22.5". Right around 4.5" deep from mounting face to rearmost plastic.

It's priced pretty fair new (see PVK's link), but I found a pretty awesome source. Apparently those companies doing engine conversions are dumping them in near-new condition dirt cheap. I just received a new looking 850w for $135 with free shipping. Of course I'm sure they will run out, but I was blown away (it shows $270 until you select an option between the 850w) or the 600w)

Mopar Radiator Fan Cooling Module Complete with Shroud; Wrangler JL & Gladiator JT

Genuine Mopar Part Mopar 68272755 or 68282799 Removed from Low Mileage JLs & JTs Includes Fan, Motor, and Shroud Fits: 2018+ Wrangler JL, 2020+ Gladiator JT

www.rubitrux.com

It's about the perfect size for the radiator of a WJ, so I just need to decide how I want to control it, standalone or integrated into the OEM fan control

I have been stuck in traffic jams the past couple of days at 100F with the A/C on. The Jeep stayed at the normal engine temperature even though there is a partial blockage from the winch. That fan sounded like a airplane.

 

[HYDRODYNAMIC]

Ah, yeah. Saw that thread, then saw this:

VARIABLE PWM FAN CONTROL works with ANY sensor, compare to Lingenfelter VSFM-002 | eBay

It also has special selections for driving Solid State Relays (SSR's) to vary DC fans with no fuss. Easy 2-button programming makes setting the temperature span a snap, just run the engine and press one button at your "turn on" setpoint, another button at your "full speed" setpoint.

www.ebay.com

And yeah. Fuck it. For $65, why not?

It looks like that guy makes some quality parts at a reasonable price. Good find.

 

[HYDRODYNAMIC]

Haven't talked too much about wiring. I always used the only listed SPAL harness SBL-YAZ-PT10 on the new brushless fans but never stopped to think what wire size should be used. The VA116-ABL505P-105A, AKA the Corvette fan pulls up to 42A. The SPAL accessory harness is only 10GA. The fan itself has 8GA wire on it.

With the engine off, a fully charged car battery voltage will measure about 12.5 volts. When the engine/alternator is running, battery voltage will typically rise to 13.5 to 14.5 volts.

The fan motor needs 13VDC to reach full speed.
The SBL-YAZ-PT10 is 8FT of 10GA

CALCULATOR 1
42A @13.5VDC over 8FT on 10GA = 12.63VDC
42A @13.5VDC over 8FT on 8GA = 12.96VDC
42A @13.5VDC over 8Ft on 6GA = 13.16VDC
42A @13.5 VDC over 4FT on 10GA = 13.07VDC

CALCULATOR 2
42A @ 13.8VDC over 8FT on 10GA = 13.46VDC
42A @ 13.8VDC over 8FT on 8GA = 13.58VDC
42A @ 13.8VDC over 8FT on 6GA = 13.66VDC
42A @13.8 VDC over 4FT on 10GA = 13.63VDC

Luckily on my setup the battery is about 4 FT away from the high output fans.
Moral of the story is you might need to run some thicc wire that will have a tweeker foaming at the mouth. Or keep the battery close to the fans and run a longer alternator to battery wire.

 

[Rockwood]

Haven't talked too much about wiring. I always used the only listed SPAL harness SBL-YAZ-PT10 on the new brushless fans but never stopped to think what wire size should be used. The VA116-ABL505P-105A, AKA the Corvette fan pulls up to 42A. The SPAL accessory harness is only 10GA. The fan itself has 8GA wire on it.

With the engine off, a fully charged car battery voltage will measure about 12.5 volts. When the engine/alternator is running, battery voltage will typically rise to 13.5 to 14.5 volts.

The fan motor needs 13VDC to reach full speed.
The SBL-YAZ-PT10 is 8FT of 10GA

CALCULATOR 1
42A @13.5VDC over 8FT on 10GA = 12.63VDC
42A @13.5VDC over 8FT on 8GA = 12.96VDC
42A @13.5VDC over 8Ft on 6GA = 13.16VDC
42A @13.5 VDC over 4FT on 10GA = 13.07VDC

CALCULATOR 2
42A @ 13.8VDC over 8FT on 10GA = 13.46VDC
42A @ 13.8VDC over 8FT on 8GA = 13.58VDC
42A @ 13.8VDC over 8FT on 6GA = 13.66VDC
42A @13.8 VDC over 4FT on 10GA = 13.63VDC

Luckily on my setup the battery is about 4 FT away from the high output fans.
Moral of the story is you might need to run some thicc wire that will have a tweeker foaming at the mouth. Or keep the battery close to the fans and run a longer alternator to battery wire.

Camaro or JL fan thorough 10ga…

Which was why I wanted to know about the harness AgitatedPancake found. Everything I’ve seen for the Yazaki connectors was 10ga.

 

[AgitatedPancake]

Camaro or JL fan thorough 10ga…

Which was why I wanted to know about the harness AgitatedPancake found. Everything I’ve seen for the Yazaki connectors was 10ga.

Just to add a little more context to what I did - the fan itself has like 6ga wire. I went way overkill and stuffed the connector with 4ga because it’s what I had. It wasn’t made for wire that big though so the crimp wasn’t quite able to grab all the strands. I ended up soldering as well for extra insurance. The provided silicone grommets won’t fit either, so I’m going to have to put some sealant in the connector when I go for final assembly.

Probably not worth the hassle, but I didn’t want to wait for more appropriately sized wire

 

[Bebop]

I wonder what the factory used...

 

[AgitatedPancake]

I wonder what the factory used...

From the pics I’ve seen it looks pretty decent sized, 6ga is my guess. Here’s a link to a forum post, and a pic from that thread for size reference:

Radiator Fan Wiring Harness

So I needed to take my airbox out to route my winch wiring the way I wanted. The airbox grommets were fairly stiff pulling it out. The radiator fan connector got smacked when taking the box out and the locking tab broke off the connector. I'm wondering if anyone knows the part number for just...

www.jlwranglerforums.com

 

[Bebop]

factory wiring is in mm2, not AWG

 

[Rockwood]

From the pics I’ve seen it looks pretty decent sized, 6ga is my guess. Here’s a link to a forum post, and a pic from that thread for size reference:

Radiator Fan Wiring Harness

So I needed to take my airbox out to route my winch wiring the way I wanted. The airbox grommets were fairly stiff pulling it out. The radiator fan connector got smacked when taking the box out and the locking tab broke off the connector. I'm wondering if anyone knows the part number for just...

www.jlwranglerforums.com

Dayum. Pretty sure that’s the same size my XJ’s starter came with, definitely bigger than the hilariously undersized stock alternator wiring.

 

[Isdtbower]

I just got done re-wiring the alt to starter circuit in a buddies hot rod. The builder had used 10ga wire and then used a 175 amp fuse to protect the "fuse block." He kept having a low battery. I had him turn on all his circuits, including AC and fan, and clamped each main wire for amps. His max was 75amps. The alternator was a 210. I used 6ga from the alt to the starter with a 125amp fuse inline. (start small) And another 6ga from the starter to the fuse block with a 80 amp fuse. 70 amps was all that was needed in the fuse block.

Now, you guys, are going to make me look at the fan wiring. A real PITA under a 32 dash.......and the guy doing the wiring did a bitchen job on routing...meaning impossible to see.

I scored on a 370 amp alternator. I see that the correct size should be two 1/0 wires!!!!! Wake-up time.

Pretty common for Ultra4 rigs to need continuous 240 amps and Trucks close to 300. Two alternators for need and get back redundancy.

In the LJ, I carry a starter, alternator, and all sensors. Hub, a couple x joints, Missile rod, and etc. Computer, fuel rail, spare,etc in the truck. (I have bead locks so easy withr a tube)

Funny: I was the back gunner on a day trip. A buggy drained the battery. I was the only one of about 10 with jumper cables. Some were rentals though)

Edit: While researching wire size, I stumbled on a mention about wire resistance. Someone on the audio side had done a lot of testing and saw differences where wire size could or should be decreased/increased. Why audio stuff has a lot more information than just general auto. We already are aware of alum vs copper. This was a next level look. Always interesting to this group.

 

[mobil1syn]

factory wiring is in mm2, not AWG

were deal in freedom units in 13mm flipoff2

 

[Bebop]

were deal in freedom units in 13mm flipoff2

actually no haha.
GM is all metric these days.

 

[Isdtbower]

actually no haha.
GM is all metric these days.

why I had to snip this

 

[Bebop]

These guys have different values :

AWG to mm2 | Gauge to mm conversion

American wire gauge (AWG) to mm and mm2 conversion calculator, chart and how to convert.

www.rapidtables.com

 

[Rockwood]

were deal in freedom units in 13mm flipoff2

Only 2 types of countries on this planet: those that use the metric system…

And those that’ve been to the moon.

 

[YJ-6 Unlimited]

I need to double check the part numbers, but I'm pretty sure it's the same as this SPAL unit. This isn't the exact link I ordered, but looks the same. The kit that I got came with grommets and terminals for a couple different wire sizes

GENUINE NEW Replacement Connectors, Terminals and Seals for Spal Kit 30130628 Brushless Fans - Walmart.com

Dammit where was that when I was doing my PWM fan. Ended up paying like $85 for a prebuilt harness I had to modify.

 

[Rockwood]

BTW, scored a C7 brushless fan from a friend for free99. Will report back how it does on my LM7 in an XJ swap. Nothing as extreme as HYDRODYNAMIC has going, but AC set to stun and dune recoveries aren’t kind to a cooling system.

 

[Isdtbower]

Dammit where was that when I was doing my PWM fan. Ended up paying like $85 for a prebuilt harness I had to modify.

Funny. Most of us have at least three elec crimpers and wire strippers in the tool box. But this week I had several of those open barrel connectors like above. None of them worked.... Old dude so not knowing there is a "special" open barrel crimper tool is tough to digest. There is a little tit in the valley to turn the tangs into themselves. Anywhere from $10 to $400 each. And note that they are usually used on 14ga and thinner. (But I did have one for Sparkplug wires so just another technology. Showed one at hot rod breakfast this morning and only two of 10 knew the difference. Both wired for a living.

EDIT::: Allows you to wire directly to relays, weatherpacks, delphi, and etc. AND you can SEE how small some of these are...and why they might not pass the DC you really want. A relay might be rated for 30-40 amps but really only wired for 10 amps. VERY COMMON. And why many Mtrhome lights are dull.... I have wired around several of those multi connectors ... So uninformed are many engineers .... or purchasing agents. If you see something that is multi pinned (10-20), I can guarantee that there are some in there that are not going to carry the load. Kinda like a #10 wire out of a 300 amp alternator. (But your battery might not blow up)

 

[YJ-6 Unlimited]

Funny. Most of us have at least three elec crimpers and wire strippers in the tool box. But this week I had several of those open barrel connectors like above. None of them worked.... Old dude so not knowing there is a "special" open barrel crimper tool is tough to digest. There is a little tit in the valley to turn the tangs into themselves. Anywhere from $10 to $400 each. And note that they are usually used on 14ga and thinner. (But I did have one for Sparkplug wires so just another technology. Showed one at hot rod breakfast this morning and only two of 10 knew the difference. Both wired for a living.

I use this guy.

Pro'sKit 300-005 Crimper, Ratcheted, AWG 20-18, 16-14, 12-10.Non-Insulated, Open Barrel terminals, Multi Amazon.com

 

[WaterH]

Not sure if this is the right place to ask this, but here goes.

I have a radiator with 2 Spal DC fans. They are side mounted and get no “ram” air. I currently have them mounted sucking the air through the rad and blowing out the side of the truck. So they are sucking some hot air from the engine compartment. The truck does run some what hot. This motor is supposed to be cold blooded and I have an over sized radiator which would indicate that my setup might not be ideal.

The truck always runs cool if I’m going slow and if I’m going fast and it gets hot, it will cool down quickly if I slow down. This leads me to believe there are aero dynamic issues with the side mounted rad.

Ive always wanted to run the fans backwards (sucking in the side and blowing under the truck), and to day I tested that. It ran hotter than shit, but I’m not sure it was a fair test.

What I did was swap the pos and neg wires and the fans turned backwards. While that was a easy way to test, there’s a couple problems.

1. It Made the fan setup a pusher instead of a puller.
2. The fans are a scimitar design and I’m not sure if they lend them selves to running backwards.

I did a bunch of net research and it suggested that a pusher is 20% less efficient than a puller. Would the experts on here agree? I couldn’t find anything about running a scimitar blade backwards. Does anybody know how much efficiency that would lose? Also, I assume swapping the wires is no problem for efficiency. Would that be correct?

 

[Bebop]

Your setup that pulls hot air to go across the rad is terrible.
You setup that shares IC coolant with the engine is also terrible.

To answer your questions, you need pusher specific fans, you can't just flip the wires and make them run backwards.
A lot of the lost efficiency of the pusher setup is due to the loss in rad surface that is in contact with the cool air.

 

[WaterH]

Your setup that pulls hot air to go across the rad is terrible.
You setup that shares IC coolant with the engine is also terrible.

To answer your questions, you need pusher specific fans, you can't just flip the wires and make them run backwards.
A lot of the lost efficiency of the pusher setup is due to the loss in rad surface that is in contact with the cool air.

A little negative response there. When you say “pulls hot air” , that’s a bit misleading. It pulls air from under the truck. The truck has 3 feet of ground clearance. Is some of the air warmer than ambient? Probubly, but at 60 mph, I doubt much.

The IC setup is done on lots of stock trucks. Again it may not be ideal, but to say terrible is a bit strong. When I did my recent test where I separated the IC from the engine, it made very little difference.

Setting all that aside, the question is how much efficiency is lost due to pusher and how much is lost to turning a scimitar backwards?

 

[Bebop]

A little negative response there. When you say “pulls hot air” , that’s a bit misleading. It pulls air from under the truck. The truck has 3 feet of ground clearance. Is some of the air warmer than ambient? Probubly, but at 60 mph, I doubt much.

At 60 it doesn't pull any air. You got a big ol stagnant air pocket.

The IC setup is done on lots of stock trucks.

Not on trucks that work.

Again it may not be ideal, but to say terrible is a bit strong.

I disagree

When I did my recent test where I separated the IC from the engine, it made very little difference.

I think your test was flawed.

Setting all that aside, the question is how much efficiency is lost due to pusher and how much is lost to turning a scimitar backwards?

No idea. If I tell you 30%, what are you going to do with that number ?