Replace A/C Evaporator core & Expansion Valve (2 Viewers)
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Any updates on this? Any write up or pics available for 100 series front evaporator removal and replacement? I have not had AC since I bought my 2002 LC [231K mi] in 2017 (a known issue when I bought it....) . So far, I have capped off the rear lines (corroded), replaced the condenser; and it still loses pressure over about 3-4 days each time it is charged......and now the local mechanic (not a dealer) says I need to replace the front evaporator....and it would cost north of $800 because "the entire dash needs to come out". I don't think he wants to tackle it, IMO. So here I am! I am reasonably mechanically competent (I can generally remove and replace, taking my time). I will have a garage pressurize the system, etc if I am able to remove and replace. Thanks!!
No need to remove entire dash to replace the evaporator, there is a 'work around'. But the Evaporator is one of the more common components to develop a leak.
Thanks I have looked around and picked up some threads here on this issue, I am going to tackle this in the next week or so....looks like cutting the plastic rail under the dash is the way to go. I'll see if I can remove the evap first.... before I spend the # to order a new one......I hope to document with pics and commentary as I work thru it...
Is Denso the preferred Evaporator Core and Expansion Valve brand? Seems to be priced significantly higher than other offerings. Trying to put together a complete list of items for the job on RockAuto.com now.
Evaporator Core- DENSO 4760046 #8850160190 Front; Front A/C $143.79
Expansion Valve- DENSO 4752024 Front; To 01/2002, Front A/C $15.66
Cabin Air Filters- 2 per pack- DENSO 4531001 #8856860010 $12.04
Oil- UAC RO0900B PAG 46 (R-134a) Oil $5.54
FOUR SEASONS 26749 Hose End Seals $9.58
Evaporator Core- DENSO 4760046 #8850160190 Front; Front A/C $143.79
Expansion Valve- DENSO 4752024 Front; To 01/2002, Front A/C $15.66
Cabin Air Filters- 2 per pack- DENSO 4531001 #8856860010 $12.04
Oil- UAC RO0900B PAG 46 (R-134a) Oil $5.54
FOUR SEASONS 26749 Hose End Seals $9.58
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You can save money going aftermarket on the Evaporator itself (maybe $50.00) but definitely go Denso on the TXV. Also, consider how difficult it is to reach and replace either item...then purchase accordingly. If you intend to keep the vehicle for some time...then Denso is your best bet IMO.
Exactly my thinking. Going to start disassembling and see how far I can get. If I hit a stopping point I'll punt and take it to the shop but either way I'll know i used the best products available. I have always used Denso products on the LX but there was a $100 difference on the cores. Being without A/C for the past few months in the south I want it done and working right!
Sorry to bog down the thread with more questions but how soon do you need to have the system hooked up to the vacum after removal and install? I have a few hours to dedicate to removal and install tonight but cant get my hands on a vacum to seak so I may have to take it in to the shop and have them do it for me when they can fit me in. Long short, I dont want to risk messing up the new core and expansion valve if it shouldn't be sitting hooked back up.
Good evening...I'm replacing my evap core and pressure valve now; and am interested if you have the Toyota part numbers for those round allen-head screws you mention above. I was able to get mine off, finally, but they seemed over-torqued also and the threads look suspect and Id rather not use them again. I did find some hex-head screws at local hardware store that I think will work fine, however I would like to replace with OEM type part if I can source it.......If you have the part number may save some time at the dealership. Thanks!!
Nevermind, the Toyota part number for those bolts is: 90099-04497. They are $2.97. I am picking up today and will post pic of package.
Regards
I didnt have any luck with paper clips so I tool one of my daughters Bobby pins and cut it. Worked perfectly. Now I have been trying to figure out how to remove evaporator core without a cut but dont see it happening. Getting hacksaw now
I have some photos to share on my evap job. Regarding cutting the plastic strip; I used a very sharp brand new carbide-blade cutter--just grip it very strongly and trace along where you want to cut (like cutting drywall). This is so sharp that about 5 passes with the blade held firmly in both hands will score and cut the strip easily.
For the repair of the cut I used a small metal brace that I had to cut in half (I only used the smaller half with two holes--one for the left side and one for the right side. Two small screws/bolts inserted through small holes I drilled in the plastic make this stronger than the original...
To remove the evap core you will have to get a pair of channel lock pliers and bend one of the braces out of the way. Also, one of the phillips head screws (out of 8 total) that the plastic front of the evap core has is right behind/under this brace. It bends easily and can be returned to original position easily also.
Before starting this job order the two screws that are inserted into the expansion valve from Toyota. They are less than $3 apiece and you will likely need them. A note on removing these screws: DO NOT use a power screwdriver; instead insert the allen wrench, place unit between your feet; and while standing over it press down very slowly but strongly. I thought the allen wrench was going to break...it was bowing a little but finally it gave just a tiny bit. Then squirt some PB Blaster on it and apply strong, CONSISTENT pressure on the bolt again. It will move a little more; spray a little more PB; and continue. Have patience but don't throw a bunch of acute torque on it or you may do damage to the head, etc. Mine came out but looked pretty bad after 19 years...so the less-than $6 replacement screws are a no-brainer.
For the repair of the cut I used a small metal brace that I had to cut in half (I only used the smaller half with two holes--one for the left side and one for the right side. Two small screws/bolts inserted through small holes I drilled in the plastic make this stronger than the original...
To remove the evap core you will have to get a pair of channel lock pliers and bend one of the braces out of the way. Also, one of the phillips head screws (out of 8 total) that the plastic front of the evap core has is right behind/under this brace. It bends easily and can be returned to original position easily also.
Before starting this job order the two screws that are inserted into the expansion valve from Toyota. They are less than $3 apiece and you will likely need them. A note on removing these screws: DO NOT use a power screwdriver; instead insert the allen wrench, place unit between your feet; and while standing over it press down very slowly but strongly. I thought the allen wrench was going to break...it was bowing a little but finally it gave just a tiny bit. Then squirt some PB Blaster on it and apply strong, CONSISTENT pressure on the bolt again. It will move a little more; spray a little more PB; and continue. Have patience but don't throw a bunch of acute torque on it or you may do damage to the head, etc. Mine came out but looked pretty bad after 19 years...so the less-than $6 replacement screws are a no-brainer.
That thick black tape-like substance that surrounds the expan valve can be carefully peeled off and reused (at least in my case).
Here is the old evap core compared with the new one (Denso, btw). I put about 40 cc pag-46 oil into core; based on some discussion with Denso rep (a guy named Steve was VERY knowledgeable about this job and spent a lot of time on the phone going through the process related to this and auto AC systems in general...I got the number from the literature that Denso included in evap core box....which I sourced from Rock Auto). Napa sold me ester oil, which they said "can be used in place of" Pag oil. Its true that they are compatible, but ester oil is spec'd for a slightly different application...so I got the Pag oil from Advanced Auto (note: NO dyes or additives; as recommended by Denso cust service rep).
When I got the evap core out I used a 12" nylon strap/tab to ream out the drain plug in the back of the plastic evap housing...
Here is the old evap core compared with the new one (Denso, btw). I put about 40 cc pag-46 oil into core; based on some discussion with Denso rep (a guy named Steve was VERY knowledgeable about this job and spent a lot of time on the phone going through the process related to this and auto AC systems in general...I got the number from the literature that Denso included in evap core box....which I sourced from Rock Auto). Napa sold me ester oil, which they said "can be used in place of" Pag oil. Its true that they are compatible, but ester oil is spec'd for a slightly different application...so I got the Pag oil from Advanced Auto (note: NO dyes or additives; as recommended by Denso cust service rep).
When I got the evap core out I used a 12" nylon strap/tab to ream out the drain plug in the back of the plastic evap housing...
One of those very small eyeglass-type screwdrivers can be used to open up the clamps on the firewall side of the core; where it connects to the high and low pressure lines.
When the evap core is wrestled out....there is a molded styrofoam insert....mine was pretty chewed up; I saved what I could and almost used this styrofoam food container to use as a template to "repair" what remained of the original. However, I decided against that and just used what I had left. I think the only real function of this is to insulate/isolate the core from the plastic a little...
I finally wrestled it back in (a little difficult)....and included here is a pic of the finished job with the glove compartment box re-attached. You can't really see the cut/repair of that plastic cross-member.
A final thought: I don't recommend messing around with vac and re-pressurizing.....unless you really know what you are doing (I admit I don't have that expertise). I took the LC to a local recommended shop and the evac/leak test/pressurization came out to about $130. First, I discussed with the tech there that my rear-air was blocked off; so a little less refrigerant than the spec may call for is needed....I mentioned that I had it open for a few weeks, etc etc and asked about the evac procedure he would use.....maybe that all seems redundant but I have learned to not take anything for granted....I think he appreciated the info and realized I had some skin in this game. Afterwords I showed him some of my pics here and he shared some battle stories or evac jobs in Jeeps he had to do.
As of yesterday it was blowing about 38-39 deg.....lets hope that's it!
When the evap core is wrestled out....there is a molded styrofoam insert....mine was pretty chewed up; I saved what I could and almost used this styrofoam food container to use as a template to "repair" what remained of the original. However, I decided against that and just used what I had left. I think the only real function of this is to insulate/isolate the core from the plastic a little...
I finally wrestled it back in (a little difficult)....and included here is a pic of the finished job with the glove compartment box re-attached. You can't really see the cut/repair of that plastic cross-member.
A final thought: I don't recommend messing around with vac and re-pressurizing.....unless you really know what you are doing (I admit I don't have that expertise). I took the LC to a local recommended shop and the evac/leak test/pressurization came out to about $130. First, I discussed with the tech there that my rear-air was blocked off; so a little less refrigerant than the spec may call for is needed....I mentioned that I had it open for a few weeks, etc etc and asked about the evac procedure he would use.....maybe that all seems redundant but I have learned to not take anything for granted....I think he appreciated the info and realized I had some skin in this game. Afterwords I showed him some of my pics here and he shared some battle stories or evac jobs in Jeeps he had to do.
As of yesterday it was blowing about 38-39 deg.....lets hope that's it!
fooldall1
Handy Enthusiast
Sorry man, haven't been back on the forum in a while. You did right ordering the OEM- the cold/warm/cold needs the zinc plated OEMS or they can get really messed up.
how much oil should be added when replacing the evap, x valve and desiccant bag?
and if replacing the front condenser?
I think I've read that new denso evaps and condensers come with oil in them already, is that correct?
Is it possible to replace the condenser without removing the radiator? looks kind of tight in there.
I've been getting by with adding 6 ounces of 134 every 6 months. Just now it's leaked out 6 ounces in 40 days. I've been ignoring it for almost 4 years. Only now has it been easy to be almost certain it's the front evap.
and if replacing the front condenser?
I think I've read that new denso evaps and condensers come with oil in them already, is that correct?
Is it possible to replace the condenser without removing the radiator? looks kind of tight in there.
I've been getting by with adding 6 ounces of 134 every 6 months. Just now it's leaked out 6 ounces in 40 days. I've been ignoring it for almost 4 years. Only now has it been easy to be almost certain it's the front evap.
Yes, you can remove the condenser with the radiator in place. Having a ratcheting 12mm box wrench will help greatly, and not minding maybe getting your knuckles a touch scraped. But it's not a big deal.
jerryb wrote:
how much oil should be added when replacing the evap, x valve and desiccant bag?
and if replacing the front condenser?
Amounts are listed in the FSM
I think I've read that new denso evaps and condensers come with oil in them already, is that correct?
Never heard of that.
Is it possible to replace the condenser without removing the radiator? looks kind of tight in there.
Yes.
I've been getting by with adding 6 ounces of 134 every 6 months. Just now it's leaked out 6 ounces in 40 days. I've been ignoring it for almost 4 years. Only now has it been easy to be almost certain it's the front evap.
Small leaks generally aren't worth chasing down, but you are clearly past that point now.
how much oil should be added when replacing the evap, x valve and desiccant bag?
and if replacing the front condenser?
Amounts are listed in the FSM
I think I've read that new denso evaps and condensers come with oil in them already, is that correct?
Never heard of that.
Is it possible to replace the condenser without removing the radiator? looks kind of tight in there.
Yes.
I've been getting by with adding 6 ounces of 134 every 6 months. Just now it's leaked out 6 ounces in 40 days. I've been ignoring it for almost 4 years. Only now has it been easy to be almost certain it's the front evap.
Small leaks generally aren't worth chasing down, but you are clearly past that point now.
