Do I need additional electric fans to cool down the radiator or the HVAC Condenser?

[nashqadri]

Since i bought my LX450, i did a lot of work on it. The HVAC will be charged either today or tomorrow with new freon. I am curious if anyone has had to add additional fans to keep the radiator and the condenser cool. The motor has 279k miles with at par compression levels but i am not convinced yet if the HVAC will cause it to heat up since the compressor is sill factor fitted apparently. I am in SoCal and just went through some high temperatures a couple weeks ago. Would my rig hold well in that kind a' heat, i wonder. Should i just add the fans regardless since i am planning a long trip on it to the Sierra's in first week of Oct.
Thanks all.

 

[greentruck]

What symptoms are causing you to worry about this? With the exception of trhe fan clutch, the OEM system in good repair should be up to the task.

Look over the various fan clutch threads carefully to learn more about how the fan clutch works and how to modify it. A properly modded fan clutch is the number one factor in everything else working well together.

Another age-relevant factor could be your radiator. Even if properly maintained, a nearly 30 year old radiator will develop blockages. run the truck up to operating temp, then shut down. Go over the radiator with either a gloved hand or a remote reading infrared thermometer. If you can feel spots with significant temp differences, you need a new radiator. I went with brass when I did mine some years back but have swung around to the aluminum side of things because of AL's superior heat transfer capabilities.

There's plenty more, but these are the most vital.

 

[CivicFerio]

On my testing, adding an auxiliary condenser fan does help with AC performance up to 25mph and it also helps a little with engine cooling during idling on 90F+ degree days. Anything above 25mph it is the main engine driven fan that does most of the cooling and only when it reaches 55 mph when the ram effect of the air aids cooling to the radiator. This being said I cannot emphasize the importance of a good working fan clutch. Mine is the blue clutch modded with a 10K CST Toyota Silicone Fluid.

Going up the Sierras is quite demanding on our rigs especially when the ambient temperatures is above 90F+ with full load, AC on and maintaining 65-70mph. Best thing you can do is to get a scan guage or any OBD2 scanner so you can monitor your engine temperature. Ideally you don't want it to go more than 217F+ on the climbs. When this happens to me I have to intervene by shutting of the AC to prevent the ECT from climbing to rapidly.

 

[Malleus]

If your shroud isn't sealing, nothing you do is going to cool the system with any noticeable result. That's the first thing to check. If it's sealed well, and, if the radiator isn't blocked, I agree, the best next step is to increase the viscosity of the fluid in the fan clutch.

I'm a fan of three row brass radiators, simply because they cool better than the two row aluminum and they are completely repairable. IMO, the worst "improvement" Toyota made to the 80s was the permanently attached plastic radiator tanks.

Electric fans are voodoo. Engine driven fans supply the best cooling.

 

[bhsdriller]

Not needed

 

[RiverCityDave]

Not to dispute @Malleus, everything I've seen tells me dude knows his business, so **respect man**. In my experience, though, the aluminum/plastic tank radiator in my 80 lasted 25 years and 246,000 miles. I hamfistedly broke the steam vent nipple off (like about a million other people); otherwise, it worked fine. I replaced it with another. They cost around 300.00. A little more from your local dealer.

The same aluminum and plastic radiator design is in my daughter's CRV, which has also seen 25 years and 255,00 miles. My wife's GM vehicle is similar and has gone 250,000 trouble-free miles and was less than 300.00 for the AC-Delco. The OEM Honda radiator in the CRV was 187.00. That is the cost of two complete oil changes in my other vehicles. I mean seriously. At that cost, this is almost a maintenance-replacement item.

Anyway, that wasn't the question, so...

I live in Texas, and my cooling system is impeccably clean. I keep it that way. I agree with everyone who posted about the fan clutch above. It's critical, as is the shroud and the foam around it. When I am at idle, my AC drifts up a few degrees in the sweltering dog days of summer. I rigged up a pusher fan a few summers ago to test the improvements gained with a fan, and it did indeed prevent this from happening. So, bottom line, is it needed? Probably not, but does it make a difference? Yeah, it definitely does. Toyota includes the mounting points for a reason.

*not my photo

If you're ambitious, you can even tie into the factory switches to turn it on and off automatically.

A few vendors on here will sell you a complete kit to make it all easy. They tend to go in and out of stock pretty regularly. The Dr. T OEM fan is available from Amayama, PartSouq, and sometimes US vendors (at a HUGE markup, though); it's 200-ish from the overseas guys, 400 and up from the US places.

I want to emphasize that you should ensure the rest of your cooling system is working correctly before you chase any perceived problems with your AC.

 

[Malleus]

I didn't mean to suggest the aluminum radiators with plastic tanks didn't work, or last; my complaints are a) they can't be rebuilt, because you can't remove and repair/replace the tanks, and b) that useless nipple breaks off when you look at it. I've lost at least three radiators because of that. They're on the shelf awaiting a repair solution, and have been for years.

 

[mudgudgeon]

I'll agree with above. Engine fan clutch is the number 1 thing.
Electric fans shouldn't be necessary. There's 80s used all over the world in worse ( or equal) conditions than California without electric fans.

I'll vote in preference for aluminum radiator.

All things being equal, brass/copper is a better conductor of heat. But manufacturing processes and material properties for copper and aluminum aren't equal. I think aluminum wins with increased surface area and thinner materials for better heat transfer.

 

[oilbrnr]

From UAE, I’m sure with luv. Now that summer is singing her swan song here in AZ (102* at 4:50), I finally get the OEM aux fan. This weekends project to help with at idle condenser low airflow, which will help vent temps. Not for engine cooling…

 

[nashqadri]

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View attachment 3735307

From UAE, I’m sure with luv. Now that summer is singing her swan song here in AZ (102* at 4:50), I finally get the OEM aux fan. This weekends project to help with at idle condenser low airflow, which will help vent temps. Not for engine cooling…

whats the part number for that OEM fan?

 

[CivicFerio]

w

whats the part number for that OEM fan?

88590-60010

 

[greentruck]

I didn't mean to suggest the aluminum radiators with plastic tanks didn't work, or last; my complaints are a) they can't be rebuilt, because you can't remove and repair/replace the tanks, and b) that useless nipple breaks off when you look at it. I've lost at least three radiators because of that. They're on the shelf awaiting a repair solution, and have been for years.

The rebuildability of brass radiators is relative. Yes, field repairable by a small, simple shop, but as for actual field repairs, that's rather theoretical. The best you can really hope for on the trail is a field-expedient repair, something that might get you home, but which will require more attention if you do manage that. Buying a new $300 radiator makes more sense to me than worrying over what in the unrepaired part of such a several decades old radiator will fail next.

Now that nipple is rather fragile, SolveFunction makes a 3D printed nipple guard if you're feeling clumsy around it.

Ultimately such repairs are an occasional issue. In practice, the AL radiators seem to demonstrate about a 5 degree cooler water temp difference, per testing by 80 owners in Arizona. I'll take that daily cooling advantage of AL over the questionable advantage of supposed better repairability of brass to deal with the occasional failure.

 

[PEOPLES]

I have a retrofit AC in my J4 and I added 2 fans in front of the condenser. Initial plan was, to get rid of the fixed fan, which didn't work out (performance not good enough).
But it helps the AC to cool down a bit more. I did some measurements with fans on/off and the difference (vehicle in the garage) was a couple of degrees, like 3-5 or so.

 

[leonard_nemoy]

No

 

[nashqadri]

Does the Aux Fan keeps running or does it talk to the thermostat ?

 

[jonheld]

In the OEM setup, the AC condenser fan runs when the AC compressor runs. In overseas markets, there is a CDS fan relay in the fender mounted relay box to the right of the horn relay. Should be the same relay as the EFI MAIN.
The logic for the relay comes from the AC amplifier, the same circuit that runs the compressor.
This was never implemented in the US market, but can be retrofit using OEM parts. I think someone on this forum sells a kit for this.

 

[Marvelicious]

If you wire it up like Toyota intended, it's entirely designed to work with the AC system, so it wires into the same pressure switch that runs your AC compressor. It's entirely intended to improve AC performance and it's really only designed to do that when you're moving slow or stopped. That said, if you spend time stuck in traffic or wheeling slow trails, and you're like me and feel hot when the temp is over 65F, it's probably worth doing.

@jonheld beat me to the punch...

 

[nashqadri]

Thank you All for wisdom.