Changing expansion valve (2 Viewers)

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And with it the drier/accumulator.
Should I also change the evaporator, compressor and condenser while "in there".
From Rock Auto total system parts are around $450.
The compressor, expansion valve and drier are Four Seasons, the two coils are Denso OE parts.

Any one have experience with Four Seasons components?
 
I did this a couple years back, replaced the condenser, expansion valve, and drier. Resealed the compressor. Used the Four Season part, and they worked fine. It was nice having functional AC again.

That being said, buy OEM o-rings and seals. The o-rings in the set I used ended up taking a set after a year and started leaking. Talk about pissed.
 
I would just do the evaporator as replacing the other parts that you mentioned relly dosnt have any overlap with replacing the expansion valve. If their not leaking and working correctly id just address them when theres a problem. save the O-rings to go to a dealer and they will match them up, there can be multiple p/n for the O-rings and its just easier to match up
 
If you're wanting to just eliminate the possibility of something else failing 6 months or a year from now and have the time/money, go ahead and do it all. I chased a few leaks on mine, got tired of it, and replaced every piece. Problem solved. Ditto on the OEM o-rings. I noticed some slight diameter differences with the 4 Seasons o-rings vs OEM so just save yourself the headache. The o-rings were the only part I got that was 4 Seasons. Everything else was Denso from Rock Auto.
 
The research I've been doing this AM tells me to use Denso or AC DElco and to avoid Four Seasons. Apparently they are hit or miss. I'd rather not have the "miss". I hate doing a job twice.

It didn't start out as a change-it-all type job, but I figured if I need to pay to have it drained, and then pay again to have it charged, might as well do it all now instead of piecemeal over the next couple of years.
 
I've repaired the A/C on both my FZJ80s. What I do is replace the O-rings, the drier, and the expansion valve. I pull the evap unit since this is a great time to clean it. They are always full of junk, which keeps it from working its best. So, I take out the evap and clean it and put in a new expansion valve. The valves are very inexpensive.

As for O-rings, I have just used the green ones I got from Rock Auto, not OEM. Have never had an issue and it has been over five years on my first one. However, I do use Nylog Blue on all the O-rings. Someone on here, who works in refrigeration, suggested it. I figured it couldn't hurt.

I personally don't replace parts that don't need it, unless they are really cheap and I'm in there anyhow (such as expansion valve). All you risk by not doing the compressor and condenser is a few cans of refrigerant. It's not like you'll have the compressor or condenser off unless you are replacing them. By only doing the O-rings, the drier, the expansion valve, refrigerant, and PAG oil, you'll be into this less than $100.
 
When I did mine I used Denso. I did both the evaporator and the expansion valve. And compressor, and dryer, also Denso. I think all those were from RockAuto.
I was actually very surprised to find a chinese knockoff in there. It was in sad shape, and didn't have the correct foam seals on it.
A year later, I replaced the condenser as it started leaking. OEM Toyota from Beno.

Once you're in there, you might as well replace the evaporator along with the expansion valve. With that done, you shouldn't have to revisit again in many years.
 
I mean if you have money to burn sure replace the evap but otherwise... why? Definitely clean it though.
 
As for O-rings, I have just used the green ones I got from Rock Auto, not OEM. Have never had an issue and it has been over five years on my first one. However, I do use Nylog Blue on all the O-rings. Someone on here, who works in refrigeration, suggested it. I figured it couldn't hurt.


I don't do any A/C work without using Nylog. Nylog is your friend.

Nylog.jpg
 
Rusty Marlin, I'd like to add one other item that no one else has spoke about. If the rubber AC hoses on your truck have never been replaced since they were new in 1997, I'd think about changing them too while your in there. The reason for that is due to their advanced age. I've worked on more then one car where the rubber hoses looked great on the outside. But once you tested them under pressure with soapy water they were in fact leaking freon due to porosity in the hose.
 
I hadn't even thought of the hoses, excellent idea.
Nylog Blue inbound from amazon. Thanks for the tip.
Ok so No to the condenser and evaporator cores.
Yes to Compressor, soft lines, valve cores (can't believe I didn't think of that earlier), expansion valve, drier and seal kit.
Roughly $600 in parts. BTW according to the Toyota dealer I order many of my OEM parts from the OEM seals are NLA. Seems odd, :meh:.
It'll be interesting to see how much the local shop charges me for 134A recovery and then recharging after I get all the parts installed.
 
I hadn't even thought of the hoses, excellent idea.
Nylog Blue inbound from amazon. Thanks for the tip.
Ok so No to the condenser and evaporator cores.
Yes to Compressor, soft lines, valve cores (can't believe I didn't think of that earlier), expansion valve, drier and seal kit.
Roughly $600 in parts. BTW according to the Toyota dealer I order many of my OEM parts from the OEM seals are NLA. Seems odd, :meh:.
It'll be interesting to see how much the local shop charges me for 134A recovery and then recharging after I get all the parts installed.
Is your compressor bad? Is your system charged and not working? If it isn't working, I would suspect that it isn't charged and so no recovery. And you can easily charge this yourself. Just get the loaner manifold and vacuum pump from somewhere like Auto Zone. This is really a pretty straight forward DIY project.
 
Its charged. Its not cooling.
The pressure side and suction side will run so hot the tubes will burn you if you brush against them.
I disconnected the clutch wire so it couldn't automatically turn on. I have no idea how long it ran like this under PO and I'm concerned that as soon as I get it up and running, the compressor will die from PO abuse. So for piece of mind I'll change it out.
I'll look into the rental thing. I hate paying people for things I can do.
 
I bought an old Durango many years ago, the AC did not work, yet the compressor was spinning. Figured it was low on refridgerant, so went about topping it up. When I put the gauges on, they were reading sky high. Turns out you can have too much in there, and it doesn't work if you do. Maybe your PO did something similar...
 
It's been two years since I looked at it, but I recall the gauge on the can being in the green. I have manifold gauges now; I'll need to hang the AC belt and plug the clutch back in this week after work and see if my memory is still good.
It won't hurt anything to look. Heck after two years there may not be anything in there if it's developed a leak while I wasn't caring about AC.
 
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Take a good look at the evaporator core while you're at it. Because it can accumulate a bunch of gunk from the outside world, that stuff can accelerate corrosion of the aluminum. If it looks questionable after cleaning, maybe consider replacement. (I spent a couple of hours cleaning mine in the hopes of reusing it, and discovered that the aluminum was badly pitted where rotting leaves had accumulated. Probably very close to becoming a leaker.)
 
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Take a good look at the evaporator core while you'er at it. Because it can accumulate a bunch of gunk from the outside world, that stuff can accelerate corrosion of the aluminum. If it look questionable after cleaning, maybe consider replacement. (I spent a couple of hours cleaning mine in the hopes of reusing it, and discovered that the aluminum was badly pitted where rotting leaves had accumulated. Probably very close to becoming a leaker.)

Very common in lower left corner. If there is any doubt the integrity of the unit....I advise replacement. Fortunately, aftermarket units are available for not much money and are perfectly serviceable (just buy from a reputable source). It's not worth having to go back in there later.
 
I have a question on the new compressor instructions.
They discuss the oil that is in the compressor and that it needs to be compared to the volume of oil in the old compressor, and reduce the new volume to match the old compressor's volume.
They show a picture of pouring out the oil from the old compressor and comparing that volume to the oil in the new compressor and then making sure they are equal. I assume this is because there is some oil trapped in the system that is not in the old compressor.
I am changing out the everything but the condenser. Do I need to attempt to drain and measure any oil I get out of the evaporator coil and dryer too? This seems logical, but I have never seen mention of it anywhere.

Or I could be totally overthinking this....
 
I have a question on the new compressor instructions.
They discuss the oil that is in the compressor and that it needs to be compared to the volume of oil in the old compressor, and reduce the new volume to match the old compressor's volume.
They show a picture of pouring out the oil from the old compressor and comparing that volume to the oil in the new compressor and then making sure they are equal. I assume this is because there is some oil trapped in the system that is not in the old compressor.
I am changing out the everything but the condenser. Do I need to attempt to drain and measure any oil I get out of the evaporator coil and dryer too? This seems logical, but I have never seen mention of it anywhere.

Or I could be totally overthinking this....


You have it right. The assumption is that there remains oil in the system (when only changing out the compressor). We don't want too much oil in the system...as it will result in diminished cooling. BUT...when you are changing other components and/or have flushed the system...then we need to consider how much oil to add back (total).

The 80 series (R134a system) uses about 8 ozs. of PAG46 oil total. The Compressor uses about 4 ozs. of that and the other components (as well as the refrigerant circulating the oil) contain the rest.

Evaporator: 40 cc (1.4 fl.oz.)
Receiver: 10 cc (0.35 fl.oz.)
Condenser: 40 cc (1.4 fl.oz.)

When draining a new compressor you won't get every bit of it out...but there isn't much you can do about that. I don't like to use the oil shipped in the compressor, but prefer to start with a new bottle of PAG46. So in your situation...drain as much oil from the compressor as you can. Add 1.5 oz to your Evaporator, Add .5 oz to the new Drier, Add 1 oz. to your condenser (just so we'll be sure) and then Add 4 ozs. to new compressor. You should be fine.

You can be a 'little' over the recommended amount of oil and not have cooling suffer. Too little will result in accelerated wear on the compressor.

Be sure to pull a deep vacuum the system before recharging with refrigerant. If you have any other questions...be sure to ask. There are several folks here that can help. You don't want to do A/C work twice.

Flint.
 

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