Flushing A/C Lines?

[LazarusTaxa]

I need to rebuild my AC system after the compressor seized.. I've got a new compressor and condenser and will be ordering new expansion valves. I might also order new evaporators as well for peace of mind... Denso units are only ~$170 each, so not terribly expensive.

BUT, I need to flush all the A/C lines, and I understand that I shouldn't flush lines with mufflers in them and instead should replace them. I am also finding out that it's typically only the high-pressure lines that have mufflers? That's confusing because both mufflers on the 100 are found on suction/low pressure lines.

I can easily source a new suction line heading into the compressor.. Rock auto sells one from Four Seasons. BUT, I can't easily find the suction line that joins the evap output from the dash with the evap output from the rear AC.

So, do I really need to replace these lines with the mufflers? Are they actually mufflers or are they actually just hollow expansion tanks??

And, while I'm on the topic, does anyone have any tips for flushing all these lines? Especially the lines running to the rear AC?

Muffler line i can find:

Muffler line i can't find:

 

[styran]

I need to rebuild my AC system after the compressor seized.. I've got a new compressor and condenser and will be ordering new expansion valves. I might also order new evaporators as well for peace of mind... Denso units are only ~$170 each, so not terribly expensive.

BUT, I need to flush all the A/C lines, and I understand that I shouldn't flush lines with mufflers in them and instead should replace them. I am also finding out that it's typically only the high-pressure lines that have mufflers? That's confusing because both mufflers on the 100 are found on suction/low pressure lines.

I can easily source a new suction line heading into the compressor.. Rock auto sells one from Four Seasons. BUT, I can't easily find the suction line that joins the evap output from the dash with the evap output from the rear AC.

So, do I really need to replace these lines with the mufflers? Are they actually mufflers or are they actually just hollow expansion tanks??

And, while I'm on the topic, does anyone have any tips for flushing all these lines? Especially the lines running to the rear AC?

Muffler line i can find:
View attachment 4147285

Muffler line i can't find:

View attachment 4147286

Have you checked the parts diagrams? you can probably find the line there and buy from dealership.
Flushing with rear AC is going to be a pain in the ass.
you're gonna have to remove the rear quarter panel, open up the rear HVAC case, disconnect rear expansion valve and remove rear evap to flush that separately from the lines
I have the rare single AC model, so lucky me I guess.

Yes you need to replace the mufflers, compressor, condenser, drier (part of condenser).
Buy a flush gun. 4 uncles makes one. I like to flush with 100% IPA and nitrogen (nitrogen will help reduce evacuation time). remember PAG oil is hygroscopic. you need to limit the oil and system exposure to the atmopshere at all costs. theres a reason all new AC parts come covered.
some people like using dura flush instead of IPA. i like IPA causes its cheap.

my mentor always says "compressors don't fail, they are murdered."
whether it be by low refrigerant, letting moisture get into the oil, whatever.

Highly recommend you stick on OE parts on this one. as you want to do this once and never again.
Denso sells most of the AC system. they do not sell the condenser, you'll need to pay premium at the dealership for that.
there are 2 different condensers, one for single and dual ac. dont get the wrong one.
not sure if denso sells the rear evaporator/rear expansion valve.
technically you're supposed to yank the dash for the evaporator, but many get away with cutting a bracket underneath the glove box to get it out.

if you are going to recharge the system, please know what you are doing or hire someone who knows what they are doing. they must have an EPA cert to work on these systems.
you are going to need a very long vacuum before charging. and be very quick to start the vacuum as soon as you open up the condenser (containers the drier) to the atmosphere. youll know youre ready for charging when you can get start getting steady reading <1000 microns. on my vehicles I shoot for under 500. but i like everything perfect.
If you need LC AC parts, I have some sitting on my shelves I probably won't ever use I can sell you.
I live on the other side of the cascades from you. I can help you with recovery/evacuation/recharge for a fee

 

[LazarusTaxa]

Thanks for your responses, this is super helpful. I've added some responses below in red...

Have you checked the parts diagrams? you can probably find the line there and buy from dealership.
Flushing with rear AC is going to be a pain in the ass.
you're gonna have to remove the rear quarter panel, open up the rear HVAC case, disconnect rear expansion valve and remove rear evap to flush that separately from the lines
I have the rare single AC model, so lucky me I guess.

I can get one of the suction lines with a manifold from rock auto (made by four seasons).. The other I do think i can actually get from Toyota. But, instead, the local AC/Rad shop says that for around $50 they can just cut the manifold out and use some rubber tubing in it's place. I think this is the route i'll go as the line from toyota is $300+

I'll be having the rad shop flush the lines for me.. I'll be disassembling everything and bringing the truck to them. They've got the equipment and I can be sure it's done right. He didn't seem concerned about flushing the lines going front to rear.

Yes you need to replace the mufflers, compressor, condenser, drier (part of condenser).
Buy a flush gun. 4 uncles makes one. I like to flush with 100% IPA and nitrogen (nitrogen will help reduce evacuation time). remember PAG oil is hygroscopic. you need to limit the oil and system exposure to the atmopshere at all costs. theres a reason all new AC parts come covered.
some people like using dura flush instead of IPA. i like IPA causes its cheap.

I have a new Denso compressor and a Toyota condenser. I'm going to be ordering new expansion valves (Denso for front, Four Seasons for rear) and a new suction hose with the muffler. Do you think I should also order new Denso evaporators? The AC shop seems pretty confident they can flush them well, but he also said it doesn't hurt to buy new ones. Again, saving $340 would be cool.

my mentor always says "compressors don't fail, they are murdered."
whether it be by low refrigerant, letting moisture get into the oil, whatever.

Highly recommend you stick on OE parts on this one. as you want to do this once and never again.
Denso sells most of the AC system. they do not sell the condenser, you'll need to pay premium at the dealership for that.
there are 2 different condensers, one for single and dual ac. dont get the wrong one.
not sure if denso sells the rear evaporator/rear expansion valve.
technically you're supposed to yank the dash for the evaporator, but many get away with cutting a bracket underneath the glove box to get it out.

Hopefully i got the right condenser.. Pretty sure I did as I checked diagrams on partsouq and searched the forum. I went with 88460-60903. For everything else, I'm ordering Denso wherever possible and Four Seasons where it's not (rear expansion valve, suction hose with muffler)

No idea why the original compressor failed. To my knowledge, it doesn't have a leak and there haven't ever been issues with the AC system...

if you are going to recharge the system, please know what you are doing or hire someone who knows what they are doing. they must have an EPA cert to work on these systems.
you are going to need a very long vacuum before charging. and be very quick to start the vacuum as soon as you open up the condenser (containers the drier) to the atmosphere. youll know youre ready for charging when you can get start getting steady reading <1000 microns. on my vehicles I shoot for under 500. but i like everything perfect.
If you need LC AC parts, I have some sitting on my shelves I probably won't ever use I can sell you.
I live on the other side of the cascades from you. I can help you with recovery/evacuation/recharge for a fee

Do you have one of those suction lines coming from the dash and rear AC? That might be a big help...

I've done limited AC work before; I replaced everything in my 60 and recharged it. I've got gauges and will rent a vacuum pump from O'Reilly (last one I rented was brand new). I'll be sure to pull a super long vacuum to ensure all the moisture is fully boiled off. I'll also of course, be sure to seal off the system and pull vacuum as soon as the condenser/drier is opened and installed.

 

[styran]

Thanks for your responses, this is super helpful. I've added some responses below in red...



I can get one of the suction lines with a manifold from rock auto (made by four seasons).. The other I do think i can actually get from Toyota. But, instead, the local AC/Rad shop says that for around $50 they can just cut the manifold out and use some rubber tubing in it's place. I think this is the route i'll go as the line from toyota is $300+

I'll be having the rad shop flush the lines for me.. I'll be disassembling everything and bringing the truck to them. They've got the equipment and I can be sure it's done right. He didn't seem concerned about flushing the lines going front to rear.



I have a new Denso compressor and a Toyota condenser. I'm going to be ordering new expansion valves (Denso for front, Four Seasons for rear) and a new suction hose with the muffler. Do you think I should also order new Denso evaporators? The AC shop seems pretty confident they can flush them well, but he also said it doesn't hurt to buy new ones. Again, saving $340 would be cool.



Hopefully i got the right condenser.. Pretty sure I did as I checked diagrams on partsouq and searched the forum. I went with 88460-60903. For everything else, I'm ordering Denso wherever possible and Four Seasons where it's not (rear expansion valve, suction hose with muffler)

No idea why the original compressor failed. To my knowledge, it doesn't have a leak and there haven't ever been issues with the AC system...


Do you have one of those suction lines coming from the dash and rear AC? That might be a big help...

I've done limited AC work before; I replaced everything in my 60 and recharged it. I've got gauges and will rent a vacuum pump from O'Reilly (last one I rented was brand new). I'll be sure to pull a super long vacuum to ensure all the moisture is fully boiled off. I'll also of course, be sure to seal off the system and pull vacuum as soon as the condenser/drier is opened and installed.

I do not have rear AC. so my lines are different. the only line I have with a muffler is the suction line by the compressor.
you can go to the junk yard and probably pick up the muffler line. just make sure to thoroughly flush it out as best you can and make sure there's no black death (compressor shreddings) all over it. my dealership sells it for about $250. probably can get it cheaper shipped on sale. maybe $190 if you're lucky
Recommend you try to do all the work yourself to save on the labor. its gonna be expensive with rear AC. you can replace the evaporators if you want or thoroughly flush them out.
I wouldnt go aftermarket on the rear expansion valve though. i wouldnt flush through any expansion valve. its gonna restrict the flow, that's the valves purpose. they should be removed.

if you are going to recharge yourself a refrigerant scale and micron gauge are a must. i would leave the vacuum running overnight. however long it takes to get the micron gauge down to an acceptable reading

nitrogen sweeping before hand would really help speed up the vacuuming process. and as a bonus, you can pump it up to like 150-200 psi and leave it for a bit to check for leaks. i always do that after a full system replacement/flush

 

[styran]

 

[LazarusTaxa]

Yeah, i'm not planning on flushing w/ the expansion valves in place. The evaporators are being fully removed and the expansion valves replaced. Again, I can get toyota OEM for the rear one, but it's something like $200 vs $30 for the aftermarket one.. I think i'm gonna chance it.

The shop quoted an hour of labor and can of flush to flush the lines and evaporators, so that seems like a pretty solid deal. I'd be happy to do it myself, but I don't have a real shop compressor w/ high CFM.. I've only got a tiny thing for finish nailers.