Under-hood blower motor. (1 Viewer)

[Pskhaat]

Like the 40, 60, and (fj)80 before them I would like to out an underhood blower in to pull/push heat out of the engine bay after shut off. Dumping heat helps the AC in the next start so much.

Do you think that this would be as helpful as I think it would be? Would you add a pusher fan outside the radiators on a separate/longer timer? A more high volume blower to just pull air in? Where would you mount it?

I'm even considering a 120VAC one I plug in when I pull back to my driveway.

 

[flintknapper]

Like the 40, 60, and (fj)80 before them I would like to out an underhood blower in to pull/push heat out of the engine bay after shut off. Dumping heat helps the AC in the next start so much.

Do you think that this would be as helpful as I think it would be? Would you add a pusher fan outside the radiators on a separate/longer timer? A more high volume blower to just pull air in? Where would you mount it?

I'm even considering a 120VAC one I plug in when I pull back to my driveway.

Underhood evacuation shouldn't affect the A/C very much. The heat exchange occurs at the condenser which is in front of your radiator. A pusher fan (aux fan) that will run on for a bit to help equalize the static pressure will help IF you plan to start the vehicle again in a short amount of time (10 minutes or so). But I'm not convinced that heat-soak inside the engine compartment significantly affects the lines or refrigerant.

Where possible, preventing the interior of the vehicle from getting really hot (solar gain, etc) is the key to quicker cooling.

Aux fans are good for helping move air across the condenser in low speed situations (or stop and go traffic). They DO make a difference there. I have them both on my 80 and 100 series because Texas Summers are brutal and you want all the advantages you can get.

A properly charged (and uncontaminated) system along with a good fan clutch should cool the interior in a reasonable amount of time. Aux fan is fine for low speed, but I wouldn't expect any fan that you can mount on your vehicle to provide enough CFM movement to evacuate the engine compartment if that is your train of thought.

 

[Pskhaat]

AC is one thing for sure. In fact that is literally another thread as it's performance in my 99 is terrible and no AC person agrees, "oh it's fine". It isn't.

But yes the heat soak in LCs is beyond compare. I know earlier generations had the carb blower but I was always impressed with the FJ80 ability to evacuate heat.

 

[knewstance]

What's your main goal with this? Are you having overheating issues? Or are you more concerned about the AC performance?

 

[flintknapper]

AC is one thing for sure. In fact that is literally another thread as it's performance in my 99 is terrible and no AC person agrees, "oh it's fine". It isn't.

But yes the heat soak in LCs is beyond compare. I know earlier generations had the carb blower but I was always impressed with the FJ80 ability to evacuate heat.

They A/C system in my 100 series is in tip-top shape....but even so, it will not cool the interior as quickly as the unit in my 80 series. I attribute this to more 'heat load' (increased interior space, more solar gain and better insulation) than in my 80 series. I've also noticed that the blower motor in my 80 series is more forceful when on the high setting than my LX470.

I would say the system in my LX is 'adequate' but it definitely takes longer to cool the vehicle than my 80 series does.

I don't think in either case that the reason is related to engine compartment temps because you have only the compressor and lines there. The condenser (heat exchanger) is mounted outside the engine compartment (in front of the radiator) and releases it's heat there. The other main component (the evaporator) is housed inside the vehicle behind the glove box. It's purpose is two fold:

1. Conduct heat from the cabin, transfer it to the refrigerant where it is carried away to the compressor, then condenser.
2. To eventually become a cool enough component that when air is blown across it, we get cold air from the vents, but this only happens after several cabin air exchanges.

The evaporator is an often overlooked maintenance item and should be checked periodically to see that it isn't clogged with debris. Particularly if you run your A/C on 'fresh air' instead of 'recirculation'. A dirty/clogged evaporator can't do it's job effectively.

But moreover....it is important to remember that your A/C 'system' (not unlike your cooling SYSTEM) is comprised of several components, all of which need to be working properly.

 

[abuck99]

I ve thought about ducting some airflow towards the back of the engine via blower motor like youd find in a boat engine compartment- attwood makes in line fans if you are experimenting.

For your A/C, @LandCruiserPhil offered a secondary fan kit for just that purpose. Not sure if its still available.

You might also try modding your fan clutch which will move considerably more air through the condensor.

 

[geanes]

What about hood vents? I've often thought of getting my hands on 2 of the rear pillar outboard vents (for cabin pressure equalization) and repurposing them as hood vents on each side towards the back of the hood. If I got the matching color, it would look pretty stealth and would help evacuate heat I'd think.

 

[abuck99]

^^I like your idea, but I think the challenge with hood vents you would want to have consideration for redirecting water intrusion (rain etc.) which those rear vents might do, but with out restricting air flow. Fair amount of discussion on the 80 forum with hood vents, I read that some had better success with venting at fenderwell IDK.

You have to also consider the A/C fresh air intake is right in front of where hood vents might be placed and you dont want more hot air coming there- so maybe off to outside the edges of the hood.
Aftermarket hoods are cheap, so getting one and modding it for the experiment would be an interesting project.

 

[AlpineAccess]

Isn't this what the OEM electric aux fan does in part?

If heat soak after shutting off the motor is an issue, plumb a turbo timer in to run the motor at idle for awhile or put a shutoff timer on the aux fan?

 

[flintknapper]

Isn't this what the OEM electric aux fan does in part?

If heat soak after shutting off the motor is an issue, plumb a turbo timer in to run the motor at idle for awhile or put a shutoff timer on the aux fan?

The OEM condenser/Aux fan (on the units that came with it) is designed to aid in low speed air flow through the A/C condenser and simply doesn't (can't) move enough air to evacuate the engine compartment to any meaningful degree. Only the engine cooling fan is capable of that. Also, the OEM is set up to turn on (and off) via the trinary switch, so the fan doesn't run but a few seconds after shut down. As soon as the two sides (high and low) begin to equalize...they reach a medium pressure which shuts the fan off.

Yes, it could be put on a timer or temperature probe, but its an inefficient way to address engine compartment heat soak...which is not the issue causing poor A/C performance to start with.

 

[geanes]

^^I like your idea, but I think the challenge with hood vents you would want to have consideration for redirecting water intrusion (rain etc.) which those rear vents might do, but with out restricting air flow. Fair amount of discussion on the 80 forum with hood vents, I read that some had better success with venting at fenderwell IDK.

You have to also consider the A/C fresh air intake is right in front of where hood vents might be placed and you dont want more hot air coming there- so maybe off to outside the edges of the hood.
Aftermarket hoods are cheap, so getting one and modding it for the experiment would be an interesting project.

I have a "dorkel" on mine....so the fresh air is coming from up high I was thinking of definitely placing them in the rear "corners" of the hood. The angle of the vents matches the lines of the hood pretty well. Figure I've already cut a 4.5" hole in one fender and other holes as well.....what's another 2 in the hood, right? LOL

 

[Patassa]

Have you given your condenser and evaporators a good thorough cleaning? Also, cleaned the a/C blower fan blades? All three of those can make a significant different.

 

[gungriffin]

What about hood vents? I've often thought of getting my hands on 2 of the rear pillar outboard vents (for cabin pressure equalization) and repurposing them as hood vents on each side towards the back of the hood. If I got the matching color, it would look pretty stealth and would help evacuate heat I'd think.

This is my plan. I ordered this louver for my hood. They have a 10% off coupon right now.

Large Powder-Coated Satin- Black Hi-Flow™ - Hood Louvers | RunCool | Hood Vents For Your Vehicle -

RunCool is your source for Hood Louvers which Cool Your Engine by allowing Heat to Escape. Run Cool Hood Louvers built with Quality in Mind.

hoodlouvers.com

My goal is going to be to position them over the headers in the hood. I figure the direction of the louver opening has me protected from rain if I am moving. Also, the raised metal of the louver should help direct water around the openings when I am parked. I just don't see how very much water could get in. I will redirect any water if it proves to be an issue. When going slow in low range, I anticipate this will make a big difference in under hood temps and IAT. We will see!

 

[nissanh]

I've been considering this for some time. I even keep the hood open on all my toys after a hot summer drive since 1998! Both my corolla and 4Runner inside the garage stays hood open even right now. Attic door is pulling that hot air and off the roof.

There is a risk of getting exhaust fumes into the cabin with hood vents, a leaking exhaust manifold/pipe and AC setting at fresh air.

 

[abuck99]

I've been considering this for some time. I even keep the hood open on all my toys after a hot summer drive since 1998! Both my corolla and 4Runner inside the garage stays hood open even right now. Attic door is pulling that hot air and off the roof.

There is a risk of getting exhaust fumes into the cabin with hood vents, a leaking exhaust manifold/pipe and AC setting at fresh air.

Do the same thing in summer months- hood up after driving

 

[Pskhaat]

Isn't this what the OEM electric aux fan does in part?

If heat soak after shutting off the motor is an issue, plumb a turbo timer in to run the motor at idle for awhile or put a shutoff timer on the aux fan?

The pusher is asserted via an AC line pressure switch. Or it was so at least in the 80.

Yes I'd need to wire that up to a timed relay instead. In my experience not a lot of hear evacuate from those.

 

[Pskhaat]

Have you given your condenser and evaporators a good thorough cleaning? Also, cleaned the a/C blower fan blades? All three of those can make a significant different.

All but the evaporator. How bad is that to clean ?

 

[OEMGUY0720]

I just open the hood when I park in the garage, that makes the cooling a tad bit faster. Been doing doing this over the past 2 decades now on all my cars. It also prolongs plastic parts from being brittle.

 

[Somebodyelse5]

They A/C system in my 100 series is in tip-top shape....but even so, it will not cool the interior as quickly as the unit in my 80 series. I attribute this to more 'heat load' (increased interior space, more solar gain and better insulation) than in my 80 series. I've also noticed that the blower motor in my 80 series is more forceful when on the high setting than my LX470.

I would say the system in my LX is 'adequate' but it definitely takes longer to cool the vehicle than my 80 series does.

I don't think in either case that the reason is related to engine compartment temps because you have only the compressor and lines there. The condenser (heat exchanger) is mounted outside the engine compartment (in front of the radiator) and releases it's heat there. The other main component (the evaporator) is housed inside the vehicle behind the glove box. It's purpose is two fold:

1. Conduct heat from the cabin, transfer it to the refrigerant where it is carried away to the compressor, then condenser.
2. To eventually become a cool enough component that when air is blown across it, we get cold air from the vents, but this only happens after several cabin air exchanges.

The evaporator is an often overlooked maintenance item and should be checked periodically to see that it isn't clogged with debris. Particularly if you run your A/C on 'fresh air' instead of 'recirculation'. A dirty/clogged evaporator can't do it's job effectively.

But moreover....it is important to remember that your A/C 'system' (not unlike your cooling SYSTEM) is comprised of several components, all of which need to be working properly.

View attachment 2401741

it sounds like You understand AC, but your 100’s AC is not in tip top shape if your 80 is beating it.

it was 111F here the afternoon and I specifically drive my 100 this time of year because the AC in the 80 isn’t nearly as good.

 

[flintknapper]

it sounds like You understand AC, but your 100’s AC is not in tip top shape if your 80 is beating it.

it was 111F here the afternoon and I specifically drive my 100 this time of year because the AC in the 80 isn’t nearly as good.

^^^^

Then could it be YOUR 80 series system is not working as well as it could?

I can assure you both of my vehicles have A/C systems that are in perfect condition. The 100 series will ultimately achieve slightly cooler vent temps (owing to its superior parallel condenser) but my 80 series will cool the cabin quicker.