Another evaporator repair writeup
#1
Another evaporator repair writeup
For whatever it's worth...probably late to the game, but it was such a huge job I had to document it for anyone else who may have to go down this path.
http://www.woodjoiner.com/volvo
-Chuck
http://www.woodjoiner.com/volvo
-Chuck
#2
#4
#5
RE: Another evaporator repair writeup
Very good write up.
Where did you get info from when you started the job?
One more thing about the heater core line clips if you had removed the o-rings in the block and used the new ones they would have fit perfect.
The new o-rings should have been 2 o-rings and one plastic washer per hose.
The old have 2 o-rings and 2 washers.
Where did you get info from when you started the job?
One more thing about the heater core line clips if you had removed the o-rings in the block and used the new ones they would have fit perfect.
The new o-rings should have been 2 o-rings and one plastic washer per hose.
The old have 2 o-rings and 2 washers.
#7
RE: Another evaporator repair writeup
Nice guide, I do have a few questions though. You say that if Volvo would have put in a paper filter none of these problems would have happened, are you referring to the pollen filter? If that's the case, when did they begin putting these in? I was under the understanding that the evaporators themselves were the problem, that somehow Volvo made a mistake in producing them. If that's not the case, would I be safe in buying a used evaporator from a newer model with no leaks?
#8
RE: Another evaporator repair writeup
Thanks for the kind words. Some answers to questions:
1. The car I worked on was an ECC, not MCC unit.
2. Before I did this job, I read everything I could get my hands on, including the Volvo shop manual, and the Haynes guide. Literally weeks of research. The shop manual and Haynes were too superficial (e.g. "remove the dashboard"...uh, okay...) Information from websites was usually lacking important details -- or dead wrong. A couple of them even had you damaging, or modifying your car (!) Most of them had you doing unnessary steps (e.g. removing the top of the dashboard). So, I read everything, got a general idea of the path -- and then started with a clean sheet of paper. I'm not saying that what I documented is perfect...but I think it is pretty efficient, and keeps an eye on safety and leaving the car "stock".
3. If Volvo had put the pollen filter in this car from day one, we wouldn't be discussing this. The evaporator is aluminum, which (if allowed to dry off once in awhile) will not rot. Lacking a pollen filter, you end up with part of the unit sitting in a constant 'mud bath'. The salts and minerals attack the weld seams on the evaporator, and after awhile you get a slow leak. There's an urban legend out there that Volvo used substandard aluminum that somehow became "porous" over time. That's nonsense.
4. I'm not sure when Volvo switched to using a pollen filter. I would recommend NOT buying a used evaporator. The unit I purchased was around $140, from FCP Groton. As you can see from the pictures, it was a pretty good match for the OEM part.
One final suggestion, which I may add to the document: After I put the new evaporator in, I thought "hey, what if the new one is defective?" It may be worthwhile to blow shop air into the new unit, and either submerge it, or spray it down with soap suds to check for any defects before installing. My friend at the garage does this, and he said that every once in awhile he gets one that has a problem, and avoids the huge hassle of a re-do.
-Chuck
1. The car I worked on was an ECC, not MCC unit.
2. Before I did this job, I read everything I could get my hands on, including the Volvo shop manual, and the Haynes guide. Literally weeks of research. The shop manual and Haynes were too superficial (e.g. "remove the dashboard"...uh, okay...) Information from websites was usually lacking important details -- or dead wrong. A couple of them even had you damaging, or modifying your car (!) Most of them had you doing unnessary steps (e.g. removing the top of the dashboard). So, I read everything, got a general idea of the path -- and then started with a clean sheet of paper. I'm not saying that what I documented is perfect...but I think it is pretty efficient, and keeps an eye on safety and leaving the car "stock".
3. If Volvo had put the pollen filter in this car from day one, we wouldn't be discussing this. The evaporator is aluminum, which (if allowed to dry off once in awhile) will not rot. Lacking a pollen filter, you end up with part of the unit sitting in a constant 'mud bath'. The salts and minerals attack the weld seams on the evaporator, and after awhile you get a slow leak. There's an urban legend out there that Volvo used substandard aluminum that somehow became "porous" over time. That's nonsense.
4. I'm not sure when Volvo switched to using a pollen filter. I would recommend NOT buying a used evaporator. The unit I purchased was around $140, from FCP Groton. As you can see from the pictures, it was a pretty good match for the OEM part.
One final suggestion, which I may add to the document: After I put the new evaporator in, I thought "hey, what if the new one is defective?" It may be worthwhile to blow shop air into the new unit, and either submerge it, or spray it down with soap suds to check for any defects before installing. My friend at the garage does this, and he said that every once in awhile he gets one that has a problem, and avoids the huge hassle of a re-do.
-Chuck
#11
RE: Another evaporator repair writeup
I was just asking about the sources because I was wondering if you had used any of the info I posted.
As for the Pollen filter discussion above that is not 100% true.
The 1996 cars came with it stock. All the way up to 2000. And it didn't make it any better at all.
I have seen 1999 S70's get an evaperator every 3 years.
The main problem is that the evap stays wet most of the time and allows the corrosion to start.
Finally in about 2003 Volvo decided to come up with a kit called an "After Blow kit".
What that would do is turn the blower motor on about 15 to 20 minutes after the car is off and that would help dry the evaperator right away instead of keeping it wet.
As for the Pollen filter discussion above that is not 100% true.
The 1996 cars came with it stock. All the way up to 2000. And it didn't make it any better at all.
I have seen 1999 S70's get an evaperator every 3 years.
The main problem is that the evap stays wet most of the time and allows the corrosion to start.
Finally in about 2003 Volvo decided to come up with a kit called an "After Blow kit".
What that would do is turn the blower motor on about 15 to 20 minutes after the car is off and that would help dry the evaperator right away instead of keeping it wet.
#13
RE: Another evaporator repair writeup
ORIGINAL: jmana
Is there anything that can be used to treat the metal on the evaporator prior to putting it in that will help it resist corrosion?
Is there anything that can be used to treat the metal on the evaporator prior to putting it in that will help it resist corrosion?
I've never dug into that area, but I wonder if you can make a hole on the lowest point of that area and attach a hose & guide it out of the firewall, but this probably requires drilling a half-inch hole or whatever the diameter of the hose.
JPN
#14
#15
RE: Another evaporator repair writeup
What about some kind of spray wax? I know it probably wouldn't help much, but might get some extra life out of it. The thing that seems like a bad idea from the factory is the foam that's attached to it, I would think this would hold moisture. How come japanese cars don't have AC problems?? It seems like it's strictly a european car problem. I can't say that I've ever driven a used euro made car which had ice cold air, but have driven many 20 year old jap cars which would freeze you out.
#16
RE: Another evaporator repair writeup
ORIGINAL: jmana
What about some kind of spray wax? I know it probably wouldn't help much, but might get some extra life out of it. The thing that seems like a bad idea from the factory is the foam that's attached to it, I would think this would hold moisture. How come japanese cars don't have AC problems?? It seems like it's strictly a european car problem. I can't say that I've ever driven a used euro made car which had ice cold air, but have driven many 20 year old jap cars which would freeze you out.
What about some kind of spray wax? I know it probably wouldn't help much, but might get some extra life out of it. The thing that seems like a bad idea from the factory is the foam that's attached to it, I would think this would hold moisture. How come japanese cars don't have AC problems?? It seems like it's strictly a european car problem. I can't say that I've ever driven a used euro made car which had ice cold air, but have driven many 20 year old jap cars which would freeze you out.
I have a good answer to this; climate difference. In Sweden (and the rest of Northern Europe I believe), the average yearly ambient temp is around 60-70s I believe, and A/C is not an absolute necessity. On the other hand, summer in Japan is hot & extremely humid, and driving a car in this weather without an A/C is just insane. I personally think cars without a working A/C should be made illegal[8D].
Another factor is that in Japan, customers are valued like nowhere else (though it's changing on the negative side lately), and if a car has so many problems with the A/C, that's it for their business. I guess this explains why the A/Cs on Jap cars don't usually fail. The OEM supplier for Japanese A/C system is either Denso or Keihin. Denso is a major supplier in Japan and their products are expected to be of the highest quality or durability.
But even Japanese A/C can fail, if the owner didn't run the A/Cduringthe winter months. The A/C has to be used at least 5-10 minutes/week to get the internals lubricated, and you can do this with the heater on in winter. I would say 95% of the drivers on the road don't bother pressing the A/C button in winter, therefore the used car market is flooded with cars with no A/C.
I hope this explains the mystery[8D].
JPN
P.S: Surprisingly, the A/C compressor on my 850 is made in Japan[8D]. That notorious OEM radio is Alpine (Japanese audio mfg) I believe, as well as the climate control module being made in Japan.....well, someone gets C-.
#17
RE: Another evaporator repair writeup
The foam is needed to seal off between the evap and the box. If it wasn't sealed off the air flow would be much less than it is.
The evaperators are actually FORD evaperators.
The earlier cars used GM evaperators which they had alot of problems as well.
The evaperators are actually FORD evaperators.
The earlier cars used GM evaperators which they had alot of problems as well.
#18
RE: Another evaporator repair writeup
Tech: I found this website (volvoforums.com) well after I had completed the repair -- but if your writeup was posted anywhere on the internet, I likely read through it. I wasn't exaggerating when I said that I researched for weeks...I read everything I could get my hands on, including repair procedures for other brands/models. I also went to the library and read books about air conditioner theory and systems. So, thank you for your writeup -- I'm sure it helped me.
On the pollen filter...my car (1997) did not have one, as delivered. So, if it was supposed to be there either the factory forgot it, or if the dealer was supposed to put it in, they didn't.
I still say that the lacok of pollen filter is the overriding culprit, here. Those post-blow fixes are usually for taking care of an odor problem, and although they do dry off the evaporator, if the darn thing is caked with silt and debris the post-blow process won't have a hope of saving the evaporator. Also, even after about a half-dozen visits to my dealer, discussions with both the parts guy and the service manager, nobody even mentioned a TSB on this or mentioned a post-blow circuit retrofit.
Peace,
Chuck
On the pollen filter...my car (1997) did not have one, as delivered. So, if it was supposed to be there either the factory forgot it, or if the dealer was supposed to put it in, they didn't.
I still say that the lacok of pollen filter is the overriding culprit, here. Those post-blow fixes are usually for taking care of an odor problem, and although they do dry off the evaporator, if the darn thing is caked with silt and debris the post-blow process won't have a hope of saving the evaporator. Also, even after about a half-dozen visits to my dealer, discussions with both the parts guy and the service manager, nobody even mentioned a TSB on this or mentioned a post-blow circuit retrofit.
Peace,
Chuck
#20