C4 heater core help
Thread Starter
1st Gear
Joined: Oct 2012
Posts: 1
Likes: 0
C4 heater core help
Just wondering if any of you out there have had to DIY install a heater core in a C4 I have an 89' and am currently stuck trying to get the block box out that contains the core from under the dash. I searched the forums and google but with no luck. Any help would be greatly appreciated for this newbie!
Drifting
Joined: May 2010
Posts: 1,990
Likes: 2
From: Gaithersburg MD A member since 2007 but then the computer crashed and then the car crash loss of memory X 2
Heater core
Unfortunately I've done the replacement twice 1-92 1-93
not sure but I think there is a screw holding the cover in place yours is going to be easier than mine were. Just be sure to mark all connectors and re install with the same to same. Good luck
not sure but I think there is a screw holding the cover in place yours is going to be easier than mine were. Just be sure to mark all connectors and re install with the same to same. Good luck
Drifting
Joined: May 2007
Posts: 1,440
Likes: 19
From: SW Chicago Burbs IL
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Huh. Don't know what to say. I did get "aggressive" with the one I was doing. Everything is so sloppily assembled in these things though, it would surprise me if 'manufacturers tolerances' allowed me to while prohibiting you.
Racer
Joined: Sep 2005
Posts: 353
Likes: 6
From: Hamilton Ohio
Heater core removal
I took the heater core out of my 89 Coupe and I hope I never have to do it again. That said, I took the passenger seat and rails out so I could lay down flat, much easier on the back. There are 7 mm screws holding the black box cover in place. There is one right in the center on the top that was the hardest to get out and I never did get it back in. I also had to remove an angle brace to gain clearance. I did remove the black box completely but being able to just slide it out the bottom would be nice. While you have all this apart, check out the motor that moves the blend door. If in doubt, replace it. Be careful with that rod.
If you are having problems with air flow through the heater you might want to remove the fan ( in engine compartment ) and reach up in there and see if the core is covered with dirt. Cleaning this out made my air flow 200 % better. I washed the core with a broken toothbrush and soapy water. Not easy to do but it makes a big difference in air flow.
If you are having problems with air flow through the heater you might want to remove the fan ( in engine compartment ) and reach up in there and see if the core is covered with dirt. Cleaning this out made my air flow 200 % better. I washed the core with a broken toothbrush and soapy water. Not easy to do but it makes a big difference in air flow.
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Cruising
Joined: May 2012
Posts: 14
Likes: 1
From: Normal IL
Just replaced the heater core in my 89' It was also one of the reasons for seller selling it, piece of cake, a little tedious didn't think I was gonna put that one screw back in but I actually put all of them back in did it. I put it off for 6 months til it was cold cause I thought it was gonna be a 6-10 hour but I did the job in under 3 hours drinkin beers. I too was also amazed that cleaning the evaporator really increased airfllow.
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Two more (1989) picture threads from this forum....
http://forums.corvetteforum.com/c4-t...ol-delima.html
http://forums.corvetteforum.com/c4-t...ore-issue.html