What causes an evaporator core to leak?

Status
Not open for further replies.
Joined
Apr 27, 2010
Messages
18,423
Location
Suburban Washington DC
Not like it's in front of the car so it can get punctured by a rock. Made of aluminum and located inside the car so won't rust. Are late model Subarus known for leaking evaporators? Pretty much diagnosed it as the source of the leak in my '16. It was blowing cold last fall but nothing now. Compressor engages but low pressure on the test gauges. Recharged and air is ice cold. Used an electronic leak tester and got nothing along the lines under the hood, but as soon as put it to a dash vent, it goes off.
 
If you have the fan on your sniffer will go off if the air is blowing across it. Try blowing into your sniffer to see for your self

Evaps can fail from just bad quality, acids in the system from not vacuuming it or filling it from a can. The most common is debris in the case that stay wet and corrode the evap.
 
Aluminum(Al) can get galvanic corrosion. If Al comes in contact with copper or zinc Al acts as the sacrificial metal. It can also occur when frost on the fins melts and there are salts in the air, like at the beach.
 
Originally Posted by Chris142
If you have the fan on your sniffer will go off if the air is blowing across it. Try blowing into your sniffer to see for your self


No, it was with the a/c off.
 
Usually the passenger side floor vent is the best to use the sniffer on, typically it's closest to the heater box.
 
Originally Posted by dishdude
Usually the passenger side floor vent is the best to use the sniffer on, typically it's closest to the heater box.


The floor vent doesn't get any air conditioned air.
 
I stick the sniffer in the drain tube to test for them. I had to replace the one in my wifes 2008 CRV. I don't know why they fail, but everything does eventually..
 
Usually its a HOLE
crazy2.gif
 
Don't be surprised, you aren't alone. I've seen many 2010-2014 Subaru's with Evap core leaks. Why? I couldn't tell you. What I can tell you is that it's relatively easy to replace, does NOT require dash removal, and can be done with hand tools in a driveway in an afternoon. Just pay a shop to evacuate and recharge the system, and you'll be all set.
 
Incorrect coolant, neglected coolant or inferior/weak part.

Often it is due to coolant wearing out over time and becoming acidic which corrodes aluminum.

How often do you change your coolant and what coolant do you use?

If you can get your hands on a pH stick and check the pH of the coolant you could see if the pH is below 7.
 
Originally Posted by Gebo
Incorrect coolant, neglected coolant or inferior/weak part.

Often it is due to coolant wearing out over time and becoming acidic which corrodes aluminum.

How often do you change your coolant and what coolant do you use?

If you can get your hands on a pH stick and check the pH of the coolant you could see if the pH is below 7.

I don't think the OP is referring to a radiator... Refrigerant doesn't wear out, unless something causes it to burn (not on automotive systems). Evap coils just seem to be made weaker than they used to be, I even have issues with copper tube/aluminum fin ones now that never used to fail.
 
Originally Posted by bullwinkle
Originally Posted by Gebo
Incorrect coolant, neglected coolant or inferior/weak part.

Often it is due to coolant wearing out over time and becoming acidic which corrodes aluminum.

How often do you change your coolant and what coolant do you use?

If you can get your hands on a pH stick and check the pH of the coolant you could see if the pH is below 7.

I don't think the OP is referring to a radiator... Refrigerant doesn't wear out, unless something causes it to burn (not on automotive systems). Evap coils just seem to be made weaker than they used to be, I even have issues with copper tube/aluminum fin ones now that never used to fail.



Oops, I better go back to bed.
27.gif


Thanks bullwinkle
 
Sloppy construction of a commodity item or penny pinching by the manufacturer because they either underbid for the contract or they underestimated the failure rate. If Subaru is known for having this issue and they continue to use the same supplier then it's another issue.
 
Status
Not open for further replies.
Back
Top