C4 Corvette A/C airflow problem? (possible cheap fix)
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Team Owner
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From: Fort Knox, KY
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C4 Corvette A/C airflow problem? (possible cheap fix)
After a number of years of use you may find that the air conditioning performance of your C4 Corvette is lacking. This is especially noticeable now that the summer temps are creeping in.
There'a a simple cleaning procedure that may restore the performance of the system.
First remove the blower motor from the vehicle. You should then be able to see the evaporator core inside the blower motor housing. Take a bright flashlight and look inside the blower housing, See if your evaporator core is clogged with debris, mold or other gunk.
If it is, it's pretty easy to see why you are not getting any air into the passenger compartment of your Corvette.
Remove the resistor on the top right of the case. Take a garden hose and some light detergent such as Simple Green and hose out the evaporator core.
Take care not to get too much water into the A/C system. Make sure that the water is draining out of the drain spout. Take a blow gun with a long end and blow out the area where the resistor mounts.
Once the unit is clean of debris reinstall the blower motor, the resistor and run the system for a few minutes to completely dry it out.
There'a a simple cleaning procedure that may restore the performance of the system.
First remove the blower motor from the vehicle. You should then be able to see the evaporator core inside the blower motor housing. Take a bright flashlight and look inside the blower housing, See if your evaporator core is clogged with debris, mold or other gunk.
If it is, it's pretty easy to see why you are not getting any air into the passenger compartment of your Corvette.
Remove the resistor on the top right of the case. Take a garden hose and some light detergent such as Simple Green and hose out the evaporator core.
Take care not to get too much water into the A/C system. Make sure that the water is draining out of the drain spout. Take a blow gun with a long end and blow out the area where the resistor mounts.
Once the unit is clean of debris reinstall the blower motor, the resistor and run the system for a few minutes to completely dry it out.
Team Owner
Joined: Aug 2000
Posts: 40,156
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From: San Pedro CA
Jules! That is a GREAT method. Sure beats PurpleC4's method of cracking that case open!
I would make sure the drains are unclogged... frequently!!
My 92 has 135k miles on it, and I have never been inside that housing. It must be a mess... yuck..
I would make sure the drains are unclogged... frequently!!
My 92 has 135k miles on it, and I have never been inside that housing. It must be a mess... yuck..
Burning Brakes
Joined: Apr 2000
Posts: 980
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From: Chandler AZ
Convertibles even have it worse.
Convertibles even get a "mud blanket" on the evaporator. I have removed the resistor and flushed it a few times. I have even gone so far as to use a shop vac with a rigged small (3/4" I think) hose attached to suck out the goo in there. It is amazing how much hair, dirt, lint and even leaves get in there.
Thanks for the tip.
Thanks for the tip.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
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From: San Diego, Ca
A lot of plugged up evaporators are leaking. A/C oil destroys the foam filter glued to the inlet. Getting what's left of it off is difficult without removing it, at which time it's probably better to replace it anyway. Trying to hose it off can swamp the heater plenum and flood the interior - the weep hole is only about an eighth of an inch - so you need to be careful if you try that method.
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From: Fort Knox, KY
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Thanks for the warning SunCr. I'm gonna' take a look at mine this weekend. I have nearly 100,000 miles on my car and I'm pretty sure it's never been cleaned or removed by the previous owners.
