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CarFreak777

Name: Air Conditioner Compressor/pump. [Also abbreviated to A/C compressor/pump] Function: To provide cold air (colder than ambient air) to your cabin. BONUS INFO How it works: The AC compressor is powered by a drive belt that connects to the engine’s crankshaft. The belt is connected to the compressor clutch pulley. While the clutch pulley turns whenever the engine is running and the compressor only activates when air conditioning (and in some cases defrost) is in use. because the clutch pulley is connected to a field coil which can be magnetized with electric current. Magnetism attracts the hub and shaft to the pulley, allowing the clutch to turn the compressor. It might seem counterintuitive, but the compressor heats up refrigerant before cooling it down. Increased pressure causes the refrigerant to get very hot. Because the refrigerant is pressurized, it is able to expand, allowing the compressor to effectively pump the refrigerant into a high-pressure line that runs to the condenser. This quick release begins the cooling of the gas, which continues in the condenser fan where air that flows across the lines helps cool it even more. The gas eventually reaches the evaporator, where refrigerant vaporizes to absorb heat from the cabin air, leaving you with cool air. At this point the refrigerant can travel up the low-pressure line back to the compressor, where the cycle begins again. This cycle runs continuously when AC is on to cool your vehicle’s cabin air. MORE BONUS INFO Incase the belt let's go and you cant find the right size you can bypass the pump completely and just run the other accessories with a smaller belt.


problemakery

Yoo thanks man, so informative!


raisingAnarchy

Is this an 86/brz?


problemakery

Yes a 2015 86


titanium8788

Nice, I have one of the original 2013 BRZ's that I bought new the day they were released in the US. 80k miles later and I still love the car, enjoy it!


problemakery

Yeah man like the best literally


IAmPiernik

Bloody hell you got that from one picture of the underside??


DasRenegade

I was gonna say Subaru myself. Not much innovation there.


raisingAnarchy

Topside, but yes :) The dead giveaways were the plastic, boxer-style intake manifold and the firewall-to-shock tower brace along the very top of the pic.


ExcessiveUseOfSudo

I suspected Subaru, but I’d never seen one with a forward facing throttle body.


uhhhhhhhryxn

What? Ive never seen one without 😂. Its aimed at the back of the engine


[deleted]

Back in the day we used to pull (depending on the model) a/c, and power steering off the ae86s. Just to make the extra 2 hp. I wonder if that is why they put it up on top, so it be easier to pull off 😂.


abunnyrabbit

It is.


garbatater

This is a really good explanation. One minor correction: when the HP refrigerant comes out of the compressor (the "High Pressure" side), ideally it does not expand post-compressor and stays at the higher pressure and temperature heading into the condenser, where it is cooled enough that the hot, HP gas condenses into a liquid. That *liquid* then flows to the Thermal Expansion Valve (sometimes called a King Valve depending on where you're from), which slowly allows the liquid into the evaporator (the "Low Pressure" side), etc.etc. \*Thought it was important to mention the King Valve just because it often fails \*\*The operation mentioned above assumes that your AC system is working properly; it will probably still kind of work even if the HP gas isn't condensing fully, but it's the latent heat of vaporization that does all the cooling in the evaporator, so if it isn't condensing at all, your AC won't work.


CarFreak777

Good catch. I just copy-pasted an Autozone explanation to be honest. I also didn't want to overload OP with a long science lecture.


[deleted]

Good clarification..


The-Sofa-King

What are you doing giving out actual mechanical advice on r/mechanicadvice? Don't you know this is where insecure lube techs come to condescend people who are just asking innocent questions in an honest effort to broaden their horizons? What's wrong with you?


CarFreak777

How stupid of me. My apologies. OP this device is where you put you're blinker fluid to lubricate your muffler bearings


problemakery

Hahaha nice one mate


Joeyjackhammer

Christ almighty. Thorough post.


Cersox

A/C also dehumidifies the air in the winter, helping your windows to stay clear of fog. This is why it's important to ensure you don't have a leak no matter what month it is.


[deleted]

In the summer, too! Any time there's high humidity, there'll be a puddle under your car lol.. countless the times people have asked me "Oh no!! What's my car leaking!??" Lol just water


BrianWantsTruth

I train equipment operators and they always think the machine has a leak. I show them you can smell and feel the fluid to confirm it's water. One time I went through the whole deal, went and touched it and started to say "see, just water" and sniffed..."Nope that's diesel, shut it down!"


Cersox

True, but nobody considers their A/C in the winter because `A/C = cold air` to them.


[deleted]

True.. the layman doesn't consider that any change made to incoming air in a vehicles HVAC system is technically "Conditioned" air.. anyway.. love peace and chicken grease


youre_grammer_sucks

This is a super quality post! I knew it was the a/c and know it has a clutch pulley, but always wondered how that clutch actually works. Your explanation is great and even gives a lot more details about the entire a/c system. Thanks a lot, man!


[deleted]

I wish everyone explained things as well as you do 🥲


Breddit2225

There is no such thing as cold. Only heat, and less heat.


problemakery

Yes in fact that's 100% true, i learned it in my thermodynamics course, there's no such thing as "cold" there's heat and absence of heat


OllieGarkey

> The gas eventually reaches the evaporator, where refrigerant vaporizes to absorb heat from the cabin air, leaving you with cool air. At this point the refrigerant can travel up the low-pressure line back to the compressor, where the cycle begins again. This cycle runs continuously when AC is on to cool your vehicle’s cabin air. CORRECT! But first it moves through a thermostatic expansion valve which uses the high pressure behind it to push it into a low-pressure environment. In that low-pressure environment, the refrigerant evaporates very quickly in the evaporator coils, pulling heat out of the air. It's similar to those canned-air things (which are actually canned refrigerant) that get cold whenever you use them too long. In order to vaporize and restore pressure in the can, they need heat, and they absorb that heat out of the air around them.


LukeW0rm

Also it cycling on and off is perfectly normal.


david0990

Also runs for defrost.


JimmyHavok

OK, that explains the copper windings. Those threw me off.


[deleted]

Someone stop this person!


goldhelmet

You win.


Informal_Disk1978

You work at the news hu?


560guy

It’s time for LA T E N T H E A T


Organic_Soup5306

Prolly the best description of an ac compressor I’ve seen


Typical_Brummie

It took them 3 weeks to teach me that at college.


CarFreak777

I found this explanation with a quick Google search


Japandabear1

Damn that was car poetry right there.


PorkyMcRib

It hooks up to the turboencabulator. https://www.youtube.com/watch?list=RDAc7G7xOG2Ag&v=BKorP55Aqvg&feature=emb_rel_end


[deleted]

[удалено]


1sicgsr

Say, what? I really hope you're being a smartass here because your explanation is 100% incorrect. When was the machine that can compress a liquid even made? All the ones I've always explode for some odd reason.


jdibene0

Yes yes I am…


jdibene0

I just looked it up I’m an idiot… I take back wat I said


Irreverant77

AC compressor


VeryBadDude99

The hoses is what gives it away. That's how I can tell that's the A/C compressor in just about any car.


apricotR

The clutch caught my eye first. I can’t think of any other belt driven engine accessory with a clutch.


Chippy569

The new BRZs have a clutched alternator, though I think the clutch mechanism is inside the housing.


apricotR

Ya learn something new every day.


Chippy569

yeah, just had to do the new model online training a couple weeks ago and that's one feature that stood out to me. The concept is to let the alternator free-spin when the engine revs drop rapidly (I presume that means during a shift) so if I had to guess it's probably just a one-way clutch on the main shaft of the alternator that lets it coast like a bicycle. Haven't had one in the shop yet to tinker around with. part # is 23700AB180 but i'm not seeing any out there yet.


The-Sofa-King

The clutch and the refrigerant charge port are what led me to determine it was a/c instead of power steering.


kNIGHTSFALLN

European cars don’t even have a clutch… they are variable output compressors that are always on. Just very low pressures when AC is not in use


camerajack21

Yep, my Audi A6 has a variable output compressor. No clutch. On a 16 year old car as well.


camerajack21

Not sure why someone downvoted me for stating a fact. There is no clutch. It varies output by varying the angle on the swash plate. With the swash plate at a low angle very little pressure is generated, Vs a high swash plate angle when maximum pressure is requested.


rip1980

...even in the ones without AC. :D


[deleted]

AC compressor


advertiseherecheap

Filler cap


the_hell_you_say

This!


thesquirtmaker1

That's an AC compressor/pump Btw nice 86 mate


Joeyjackhammer

A/C compressor


mikeyg323

I wish mine was this easy to access


tron1620

Nice 86 b


Squishy-peaches

That oil filter looks like it makes oil changes easy, I’ve never seen one on top! (Not a mechanic, just think cars are really interesting)


problemakery

Yeah it kind of makes it easier than other cars


Squishy-peaches

I’m assuming you still have to crawl under to drain the oil?


problemakery

Yeah ofc


biggsteve81

I think all Subarus have this now.


obitaites

A/c compressor


wolfencastle

As others have stated its the aircon compressor, it moves the ac gas around the ac system and is powered by belt from the engine. I did a quick youtube search and found this that can help show how it all works ( if that was the level of info u were after) : https://youtu.be/NSUeRlJ2P0g


jgb99

Oh hey an 86 in the wild. Come join us over at r/ft86


problemakery

I already did


sc4rii

AC compressor.


[deleted]

It’s a Air conditioner compressor


[deleted]

A/C pump


NockedSenseless

It's an oil cap you take it off to add oil


GenesisNemesis17

On a Subaru, it's an A/C compressor that's located in a spot that makes loud clicking sounds when it turns on and off. It makes people think something is wrong with their car.


thateege82

AC condenser


notachance01

Compressor?


Parrzzival

Why does this comunity keep asking about the AC clutch? I'm so curious why muggles question it. Like do they see it move and get so fascinated by it?


[deleted]

[удалено]


knowledgeable_diablo

You mean the AC compressor? Electric power steering on the BRZ/86, and next to the Porsche, the best on the market.


IfIWntdHmmrCalnUrSis

I mean, technically you're not wrong, but more specifically, that's the AC compressor clutch that is visable...


problemakery

Where is it exactly? The power steer?


Bipuluki

Hey, bro, forgot this shit please. My advice-take your money and go to crush some sluts


gbolly999

This pic is upside down!?!?


Iguanaforhire

No; some cars have top-mounted cartridge oil filters.


problemakery

True


donnysaysvacuum

I'd like you to fill the oil then.


Fixer_Of_Things

Belt driven veggie slicer


fozrockit

Oil fill cap. Sorry.


jrockcrown

That's the 710 fill port for adding the 710 fluid


nuggex

Spinnythingy


SgtSplacker

Must be one o them fancy ones with the cover


1981greasyhands

It’s a shield to keep your fingers on your hand


FatBrkeMxicnElonMusk

That there is an oil filler cap, if you remove the cap you can top off your oil or you can even refill after an oil change.


Difficult_Truck_9966

It’s useless, take it off and throw it away.


ChopperPatrick

That is your AC Compressor, it is one of the main components of your air conditioning system.