AC repair (1 Viewer)

[Daizo]

The AC compressor has been making noise for about a month. Changed out the clutch assembly, but it didn't help. As far as I can tell, it's the original compressor. 19 years and 250k miles. Decided to go ahead and replace it.

Searched the forum and found a few tips, but couldn't find the complete write up. Figured it's my turn to give something back to this community. Got my Land Cruiser 2 years ago, and have been using ih8mud to find tutorials, but this is my first post.

Note that my car has no rear AC. The amount of refrigerant is different if you have a rear AC.

Replacement Parts

Compressor (DENSO 471-1220)
Drier (DENSO 478-1500)
Expansion valve (DENSO 475-2024)
O-ring kit (GPD 1321283)

Not sure if I am going to replace an expansion valve yet, but the compressor warranty says the replacement of the expansion valve is required. It's not expensive, so went ahead and bought it.

Was going to get the OEM compressor, drier and expansion valve from one of the Toyota dealers, but found out DENSO parts (same as OEM) from RockAuto are a lot cheaper, so I got them from RockAuto.

Fluids and Misc.

R-134a refrigerant: 21.2 - 24.7 oz, according to the sticker in the engine bay. Not purchased yet, probably DuPont Suva R-134a.
Oil: TBD oz (not noted in FSM, 7.25 oz per the data found on the internet). PAG-46 (ND-OIL 8 according to the sticker on the compressor, but it's not readily available).
O-ring lubricant/sealant (optional): Nylog Blue. The FSM says to use compressor oil (PAG), but PAG oil absorbs moisture, and some people don't recommend it. Did some search and found Nylog Blue, which is compatible with the refrigerant/oil and never gets dry.
Refrigerant leak detector dye (optional)
Condenser cleaner (optional): Nu Calgon Nu Brite

Refrigerant evacuation

Got the refrigerant evacuated at a shop. Called at least 10 places to get pricing. The lowest was $60. Higher than expected. Most shops will try to charge you for both evacuation and recharge, even if you tell them you just need evacuation. My plan is to do the vacuum and recharge by myself, with loaner tools from AutoZone.

Compressor removal

Was nervous about it because the three bolts holding the compressor are located in tight areas. The FSM says to remove the LF drive shaft , but I know some people replaced the compressor without doing that, so I tried without it.

First bolt - front top

Accessed from the bottom. Used a 14mm shallow socket, 3/8" breaker bar with a cheater pipe. It wasn't bad.

AC - Compressor Bolt 1

• Daizo
• Jul 16, 2017

Second bolt - front bottom

Accessed through the area where the tie-rod goes through. Used a 14mm socket and long 3/8" extensions. Not an exact straight shot, so a tilt socket would help.

AC - Compressor Bolt 2

• Daizo
• Jul 16, 2017

Third bolt - rear bottom

Used a 14mm deep socket (12 point), 3/8" breaker bar with a cheater pipe. Set it up from the bottom (around the LF drive shaft) so that the breaker bar points upwards through the engine bay. Tried 6 point socket first, but the bay is too tight and I couldn't insert the cheater pipe. It would have been easier if I had a helper to hold the socket from the bottom.

AC - Compressor Bolt 3.2

• Daizo
• Jul 16, 2017

AC - Compressor Bolt 3.1

• Daizo
• Jul 16, 2017

Compressor comparison

There is a slight difference between the old and new compressors.

One of the connectors is at a different location.

AC - Compressor Comparison

• Daizo
• Jul 16, 2017

Compressor oil draining and charge

The manual that came with the compressor says to drain the oil from the old compressor, measure it and put the same amount of oil in the new compressor. Tried to drain the oil from the old compressor. Nothing came out, even after leaving it upside down over night and turning the shaft... No wonder why the compressor was making noise.

Now I don't know how much oil to put in the compressor. I'm thinking about putting the following amount. Any thought?

Compressor: 3.0 oz
Condenser: 1.4 - 1.7 oz (per 2004 FSM, might be less for AC without rear)
Evaporator: 1.4 oz (per FSM)
Drier: 0.7 oz
Rest: 0.7 oz

Used the following as a reference:

http://www.denso-am.com/products/au...-compressors/practical-tip-on-compressor-oil/

Condenser removal

Removal is not really required, but I decided to do it to inspect and clean it. The FSM says to remove the oil cooler, but I just took the bolts off and moved it out of the way.

Drier removal

Failed. Used 10mm hex key. It turned a couple of times without an issue and stopped. Used a cheater pipe, but still couldn't get it out. Damaged the head. Have to buy a new condenser. Looking at the condition of the original condenser, not a bad idea to replace it anyway. Just have to wait for another week to complete...

AC - Dryer 1

• Daizo
• Jul 16, 2017

AC - Drier 2

• Daizo
• Jul 16, 2017

AC - Condenser

• Daizo
• Jul 16, 2017

To be continued...

 

[re_guderian]

Thanks for the detailed write up!

 

[Daizo]

Thanks for the detailed write up!

You are welcome!

 

[Daizo]

Hose/tubing removal

Removed all the hoses/tubing for flushing.

The FSM says to use an SST to open the tubing clamps by the expansion valve. Inserted a small flat head driver in the hole and was able to pull them apart. One of them got slightly damaged in that process, but it's still usable.

Also broke one of the rubber mount by the coolant reservoir, when I twisted the attached nut. The rubber was brittle and I should have been more careful. Oh well...

To remove the tubing between the condenser and expansion valve, took off bolts for charcoal canister and headlights, and moved them out of the way.

 

[Daizo]

Evaporator removal

Debated whether I should remove the evaporator or not, but decided to do it for a few reasons:

• When I got this car two years ago, the AC wasn't working well (slightly cool air, not cold). I took it to a shop and they said the refrigerant was low. They evacuated and recharged the refrigerant with dye. The AC worked ok afterwards (not as cold as my other cars though). They couldn't find any leak. No refrigerant has been charged since then. It was working ok (except the compressor noise), but the air didn't feel as cool as before. Not sure if it was because of the leak or failing compressor. I haven't seen any dyes leaking at the hose/tubing connections so far. If there is a leak, it must be in the evaporator or expansion valve.
• Even if there is no leak in the evaporator and no need for replacement, it's good to remove and flush it.
• I tried to drain the compressor and condenser, but nothing came out. Where did all the oil go? To charge the proper amount of oil in the system, need to know how much oil in the system currently.
• As mentioned in my first post, the expansion valve replacement is supposedly required for warranty. It is not accessible from the engine bay (I think).

Here is the picture of the removed evaporator:

Most of the dyes are at the bottom, but I can see some around the inlet/outlet as well. I can't tell whether it was leaking from the o-rings and/or coil.

I don't want to find a leak after everything is put back together. I guess I have to change out the evaporator as well...

You can find threads on how to get the evaporator core out without removing the instrument panel, so I'm not going into the detail on how. Here is the picture.

When I got this car, I had a problem with water condensation dripping through the door of the evaporator because of the failed seal. I took it off and applied Permatex clear RTV silicone. Never had a leak issue since then. It came off when I opened it to remove the core, but it is still perfectly formed and looks like I can even reuse it.

 

[tacoduck]

that evaporator looks bad... is that AC oil at the bottom of the housing? How hard was it to unattached the evaporator from the engine bay? removal after that looks pretty straight forward. I think my front evap is leaking, so thats the reason for asking. thanks!

 

[Daizo]

is that AC oil at the bottom of the housing?

Mixture of AC oil and dye, most likely.

How hard was it to unattached the evaporator from the engine bay?

Not difficult, once I figured out how to open the clamps. All you have to do on the bay side is to remove the clamps and pull the tubes.

removal after that looks pretty straight forward

Yes, straight forward. You just have to pull the panel really hard to get the core out. Even with the cut, still very tight. I thought the panel was going to break/crack, but it didn't.

 

[sean2202]

Thanks for doing this writeup. Much appreciated. My compressor has a slow leak and will need replacing at some point.

 

[Daizo]

Thanks for doing this writeup. Much appreciated. My compressor has a slow leak and will need replacing at some point.

You are welcome!

 

[tacoduck]

I've been trying to diagnose a slow AC leak in my 07 lx470. Im losing about 2 cans a month. Fired up the blacklight and I think I found my leak. does that look like an o ring issue or is my condenser shot? Wondering how hard it would be to replace the condenser? part # for the condenser? thanks!

 

[Daizo]

I've been trying to diagnose a slow AC leak in my 07 lx470. Im losing about 2 cans a month. Fired up the blacklight and I think I found my leak. does that look like an o ring issue or is my condenser shot? Wondering how hard it would be to replace the condenser? part # for the condenser? thanks!

Assuming you have UV dyes in your AC system (based on your first photo), I would probably wipe and clean that glowing area, run the AC for a while and check again to pinpoint the leak.

2 cans (24 oz?) a month sound like pretty big leak, so you should be able to spot it easily.

If you see the leak in-between the connection, then it would be o-ring most likely. You can try tightening the bolt (but don't over-tighten it) to see if it stops. If it doesn't, you need to open the system to replace the O-rings.

You can easily trace the refrigeration lines, so I would suggest inspecting each line and component. There are not many connections and they are easy to access/inspect, except the evaporator. One thing you can do on the evaporator is to check the evaporator drain (coming out from the engine bay) with the UV flashlight. If there is a leak in the evaporator, the mixture of refrigerant oil and UV dye would be drained with the condensation. You can also slide the evaporator door and take a peek.

Replacing the condenser is pretty easy. Most people/manufactures recommend replacing the drier as well, whenever the AC system is opened. It's also a good idea to flush all the piping and evaporator and replace all O-rings.

I'm not sure what type of refrigerant you have been using to refill the system, but I would be concerned about the amount of oil left in the system. In my case, most of the oil leaked with refrigerant, which resulted in poor lubrication and damage to the compressor.

To find the right part#, you can go to any Toyota dealer parts website or try the following for Denso parts:

http://densoautoparts.com/find-my-part

Please note I am familiar with refrigeration system (since I am an engineer who deals with process refrigeration), but I'm not an expert in car repairs and certainly not a mechanic. I just like doing/leaning things by myself. What I stated in this thread is simply based on my experience and knowledge.

 

[tacoduck]

One thing you can do on the evaporator is to check the evaporator drain (coming out from the engine bay) with the UV flashlight. If there is a leak in the evaporator, the mixture of refrigerant oil and UV dye would be drained with the condensation. You can also slide the evaporator door and take a peek.

Brilliant. The UV light was really helpful in finding what in hindsight was a fairly obvious leak. My compressor is running like a champ, for now. If I had to do it over again, I would prob replace the condenser, compressor, and the evaporator all in one pop. No AC on my wife's car is painful to hear about!!!

 

[YodatheLC]

I seem to have the same issue with condensation coming off the evap. Should I be conserned about this other than the minor inconvenience of my passengers feeling a drop or too of cold water? Or is this a sign of more problems to come

 

[Daizo]

I seem to have the same issue with condensation coming off the evap. Should I be conserned about this other than the minor inconvenience of my passengers feeling a drop or too of cold water? Or is this a sign of more problems to come

I think it is just a minor inconvenience and not a sign/cause of more problems. It's not difficult to fix it though.

 

[Eliot]

The AC compressor has been making noise for about a month. Changed out the clutch assembly, but it didn't help. As far as I can tell, it's the original compressor. 19 years and 250k miles. Decided to go ahead and replace it.

Searched the forum and found a few tips, but couldn't find the complete write up. Figured it's my turn to give something back to this community. Got my Land Cruiser 2 years ago, and have been using ih8mud to find tutorials, but this is my first post.

Note that my car has no rear AC. The amount of refrigerant is different if you have a rear AC.

Replacement Parts

Compressor (DENSO 471-1220)
Drier (DENSO 478-1500)
Expansion valve (DENSO 475-2024)
O-ring kit (GPD 1321283)

Not sure if I am going to replace an expansion valve yet, but the compressor warranty says the replacement of the expansion valve is required. It's not expensive, so went ahead and bought it.

Was going to get the OEM compressor, drier and expansion valve from one of the Toyota dealers, but found out DENSO parts (same as OEM) from RockAuto are a lot cheaper, so I got them from RockAuto.

Fluids and Misc.

R-134a refrigerant: 21.2 - 24.7 oz, according to the sticker in the engine bay. Not purchased yet, probably DuPont Suva R-134a.
Oil: TBD oz (not noted in FSM, 7.25 oz per the data found on the internet). PAG-46 (ND-OIL 8 according to the sticker on the compressor, but it's not readily available).
O-ring lubricant/sealant (optional): Nylog Blue. The FSM says to use compressor oil (PAG), but PAG oil absorbs moisture, and some people don't recommend it. Did some search and found Nylog Blue, which is compatible with the refrigerant/oil and never gets dry.
Refrigerant leak detector dye (optional)
Condenser cleaner (optional): Nu Calgon Nu Brite

Refrigerant evacuation

Got the refrigerant evacuated at a shop. Called at least 10 places to get pricing. The lowest was $60. Higher than expected. Most shops will try to charge you for both evacuation and recharge, even if you tell them you just need evacuation. My plan is to do the vacuum and recharge by myself, with loaner tools from AutoZone.

Compressor removal

Was nervous about it because the three bolts holding the compressor are located in tight areas. The FSM says to remove the LF drive shaft , but I know some people replaced the compressor without doing that, so I tried without it.

First bolt - front top

Accessed from the bottom. Used a 14mm shallow socket, 3/8" breaker bar with a cheater pipe. It wasn't bad.

AC - Compressor Bolt 1

• Daizo
• Jul 16, 2017

Second bolt - front bottom

Accessed through the area where the tie-rod goes through. Used a 14mm socket and long 3/8" extensions. Not an exact straight shot, so a tilt socket would help.

AC - Compressor Bolt 2

• Daizo
• Jul 16, 2017

Third bolt - rear bottom

Used a 14mm deep socket (12 point), 3/8" breaker bar with a cheater pipe. Set it up from the bottom (around the LF drive shaft) so that the breaker bar points upwards through the engine bay. Tried 6 point socket first, but the bay is too tight and I couldn't insert the cheater pipe. It would have been easier if I had a helper to hold the socket from the bottom.

AC - Compressor Bolt 3.2

• Daizo
• Jul 16, 2017

AC - Compressor Bolt 3.1

• Daizo
• Jul 16, 2017

Compressor comparison

There is a slight difference between the old and new compressors.

One of the connectors is at a different location.

AC - Compressor Comparison

• Daizo
• Jul 16, 2017

Compressor oil draining and charge

The manual that came with the compressor says to drain the oil from the old compressor, measure it and put the same amount of oil in the new compressor. Tried to drain the oil from the old compressor. Nothing came out, even after leaving it upside down over night and turning the shaft... No wonder why the compressor was making noise.

Now I don't know how much oil to put in the compressor. I'm thinking about putting the following amount. Any thought?

Compressor: 3.0 oz
Condenser: 1.4 - 1.7 oz (per 2004 FSM, might be less for AC without rear)
Evaporator: 1.4 oz (per FSM)
Drier: 0.7 oz
Rest: 0.7 oz

Used the following as a reference:

http://www.denso-am.com/products/au...-compressors/practical-tip-on-compressor-oil/

Condenser removal

Removal is not really required, but I decided to do it to inspect and clean it. The FSM says to remove the oil cooler, but I just took the bolts off and moved it out of the way.

Drier removal

Failed. Used 10mm hex key. It turned a couple of times without an issue and stopped. Used a cheater pipe, but still couldn't get it out. Damaged the head. Have to buy a new condenser. Looking at the condition of the original condenser, not a bad idea to replace it anyway. Just have to wait for another week to complete...

AC - Dryer 1

• Daizo
• Jul 16, 2017

AC - Drier 2

• Daizo
• Jul 16, 2017

AC - Condenser

• Daizo
• Jul 16, 2017

To be continued...

Daizo,

Thank you for putting this together, it is a great write up. This saved me a lot of time finding the best angles to get at the 3 bolts that hold the compressor in. I just did this job a week ago and then had the shop do the receiver dryer and the refrigerant recharge. Took me about 3.5 hours to swap compressors, but i was taking my time .

A couple notes for those looking to attempt this job:
-You'll have to use the cover from your old compressor. 4x 8mm allen bolts and the door comes off. Be sure to clean it up good before installing on the new compressor.
-If you buy a BRAND NEW Denso compressor, it will come with the oil already in it.
-If you can R&R an alternator, you can do this job. The bolts are a pain to get to and take a while to remove. Took me 20 minutes on each of the back bolts. The front bolt is easy to get to. Don't get frustrated, just be patient and take your time. These bolts are buried.
-When you pull the lines off the compressor, be sure to plug/cover them up. I just used tape to keep them sealed. Being in Charleston, CS it gets pretty humid here so you risk allowing moisture into the system.
-Once you open up the A/C system it is recommended that you replace the receiver-dryer. The shop only charged me an hour to do this.
-Cool Stream AC in Tucson, Arizona is where i sourced my parts. Ask for Jorge, he'll hook you up with good prices for MUD members.

 

[Daizo]

Daizo,

Thank you for putting this together, it is a great write up. This saved me a lot of time finding the best angles to get at the 3 bolts that hold the compressor in. I just did this job a week ago and then had the shop do the receiver dryer and the refrigerant recharge. Took me about 3.5 hours to swap compressors, but i was taking my time .

Eliot,

Glad I was able to help! I agree with your notes. I was planning to add more notes after I finished all the work, but I got busy with other stuff (rear axle seal and bearing replacement)... The AC is putting out cold air and there is no leak so far.

 

[discojon]

Thanks for the good info. I was able to remove my compressor, condensor, and a couple lines in a few hours. Unfortunately, a few of the lines were damaged at the connectors from someone else's work previously and had to be cut off and replaced. I'd like to add that removing the front bumper made my life easier when removing the old crusty condensor.

 

[r2550g]

thanks for the write-up!! it is very helpful. I am in the same situation now and needs to get the A/C compressor replaced. After having got three bolts loose, how to get the compressor out from that tiny space? did you have to remove radiator or at least the engine fan in order to get the compressor out?

Thanks a lot!!

 

[Daizo]

thanks for the write-up!! it is very helpful. I am in the same situation now and needs to get the A/C compressor replaced. After having got three bolts loose, how to get the compressor out from that tiny space? did you have to remove radiator or at least the engine fan in order to get the compressor out?

Thanks a lot!!

No problem. I'm glad it was helpful.

I remember it was really tight, but I was able to wiggle it out without removing anything else. It's been a while so I don't remember all the details but I think it had to be twisted and needed to be in a certain position to get it out and put a new one in.

 

[Pucker5]

Evaporator removal

Debated whether I should remove the evaporator or not, but decided to do it for a few reasons:

• When I got this car two years ago, the AC wasn't working well (slightly cool air, not cold). I took it to a shop and they said the refrigerant was low. They evacuated and recharged the refrigerant with dye. The AC worked ok afterwards (not as cold as my other cars though). They couldn't find any leak. No refrigerant has been charged since then. It was working ok (except the compressor noise), but the air didn't feel as cool as before. Not sure if it was because of the leak or failing compressor. I haven't seen any dyes leaking at the hose/tubing connections so far. If there is a leak, it must be in the evaporator or expansion valve.
• Even if there is no leak in the evaporator and no need for replacement, it's good to remove and flush it.
• I tried to drain the compressor and condenser, but nothing came out. Where did all the oil go? To charge the proper amount of oil in the system, need to know how much oil in the system currently.
• As mentioned in my first post, the expansion valve replacement is supposedly required for warranty. It is not accessible from the engine bay (I think).

Here is the picture of the removed evaporator:

View attachment 1499448

Most of the dyes are at the bottom, but I can see some around the inlet/outlet as well. I can't tell whether it was leaking from the o-rings and/or coil.

I don't want to find a leak after everything is put back together. I guess I have to change out the evaporator as well...

You can find threads on how to get the evaporator core out without removing the instrument panel, so I'm not going into the detail on how. Here is the picture.

View attachment 1499453

When I got this car, I had a problem with water condensation dripping through the door of the evaporator because of the failed seal. I took it off and applied Permatex clear RTV silicone. Never had a leak issue since then. It came off when I opened it to remove the core, but it is still perfectly formed and looks like I can even reuse it.

View attachment 1499459

Is that evaporator bad? I got a little bit of that yuck at the bottom corner in the same spot. I’ve had all elements of my ac replaced but that. Blows cold as s*** but was wondering if there’s a downside toman evaporator in that condition. I only saw it when I was doing my cabin air filter add to my 2003lc.