Heater core replacement
Thread Starter
3rd Gear
Joined: Sep 2024
Posts: 3
Likes: 0
Heater core replacement
I have a have a 1988 c4 I having problems with the heater core need to be replaced does that come out through the dash or does it come out off under the hood what would be the best way to take that out what tools will I need and when I replace it will that also correct the vacuums because I can't get the AC to blow out the vents it only go out of the defrost on the window please help my name is James Gilbert my number is 979-595-5582
Drifting
Joined: Aug 2002
Posts: 1,775
Likes: 125
From: Birmingham AL
Two different issues there. Fortunately, the pre 90 cars have easier access to the heater core. Still difficult. The programmer above throttle pedal is likely the issue for air flow to vents. Lots of info about both operations on the forum.
Burning Brakes
Joined: Jun 2021
Posts: 1,199
Likes: 449
From: NJ
I don’t envy you. But we will all be there one day, sooner or later. If I recall correctly, there was info on what brands were good and had good fitment. You might want to check into that before you go buying just any one. It would suck to have fitment issues when you are already doing the contortionist bit under the dash.
Pro
Joined: Nov 2013
Posts: 518
Likes: 264
From: Jasper GA
I just did this job and while your early car will be a little different, if you take your time and keep track of things, it's really not that difficult. Just lots and lots of fiddly things to take apart. Do a little googling and you will find resources for the early cars too. I bought mine from Rock Auto and it was $36 shipped to my door. Cheap part, pain in the *** job.
https://www.corvetteforum.com/forums...post1608110485
https://www.corvetteforum.com/forums...post1608110485
Melting Slicks
Joined: May 2002
Posts: 2,263
Likes: 414
From: Muskogee OK
Cruise-In VI Veteran
^^^
Step 1 at the assembly plant, levitate the heater core in the air
Step 2, tightly enclose it with as many parts as possible requiring contortionist skills so the entire caged assembly eventually resembles a car
Step 1 at the assembly plant, levitate the heater core in the air
Step 2, tightly enclose it with as many parts as possible requiring contortionist skills so the entire caged assembly eventually resembles a car
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Pro
Joined: Nov 2013
Posts: 518
Likes: 264
From: Jasper GA
Lol you guys are making it sound so bad. It’s really not a difficult job. Just have to take a LOT of stuff apart. Take your time, note where everything goes, and it’s not too horrible. The worst part is cleaning up the mess left by the blown core.
Advanced
Joined: Jun 2024
Posts: 87
Likes: 25
I have a have a 1988 c4 I having problems with the heater core need to be replaced does that come out through the dash or does it come out off under the hood what would be the best way to take that out what tools will I need and when I replace it will that also correct the vacuums because I can't get the AC to blow out the vents it only go out of the defrost on the window please help my name is James Gilbert my number is 979-595-5582
Tools are minimal and basic, screw driver, ratchets, sockets. Do yourself a favor and take the passenger seat out for "easier" access.
I'd recommend getting the factory service manual. It lists everything step by step. It's not difficult, per se, just a lot of stuff that needs to be taken out.
One thing: In my 86 there are two pairs of connectors under the dash which can be accidentally plugged into each other, making the car non-startable. Took me forever to figure out why I couldn't start the car (actually sat for years, due to lack of time to figure this out). Why they used the same connector I don't know!
Drifting
Joined: Aug 2002
Posts: 1,775
Likes: 125
From: Birmingham AL
I did this in 2011 or so on my ‘89 roadster. 2002 on my prior ‘89 coupe. What I remember the most from both was the one screw that is impossible to see. I think I used tape on the socket for the reinstall. Top side of the box, I think. Dash frame in place.
Funny memory: I had the roadster several years before the heater core replacement. Wife always said there was too much hot air in passenger footwell. Dismissed it every time. During heater core replacements, I found the issue. Heater core cover had a big crack/ hole in it. Then came the told you so.
Funny memory: I had the roadster several years before the heater core replacement. Wife always said there was too much hot air in passenger footwell. Dismissed it every time. During heater core replacements, I found the issue. Heater core cover had a big crack/ hole in it. Then came the told you so.
Advanced
Joined: Jun 2024
Posts: 87
Likes: 25
I did this in 2011 or so on my ‘89 roadster. 2002 on my prior ‘89 coupe. What I remember the most from both was the one screw that is impossible to see. I think I used tape on the socket for the reinstall. Top side of the box, I think. Dash frame in place.
Funny memory: I had the roadster several years before the heater core replacement. Wife always said there was too much hot air in passenger footwell. Dismissed it every time. During heater core replacements, I found the issue. Heater core cover had a big crack/ hole in it. Then came the told you so.
Funny memory: I had the roadster several years before the heater core replacement. Wife always said there was too much hot air in passenger footwell. Dismissed it every time. During heater core replacements, I found the issue. Heater core cover had a big crack/ hole in it. Then came the told you so.
Safety Car
Joined: Oct 2007
Posts: 4,426
Likes: 229
From: Pennsylvania
Look up "The Fast Guy Method" to change the heater core on a C4 Corvette. It's step by step instructions and fairly simple. It will save you lots of time and aggravation. You can do this job just by removing the passenger seat and knee carpeted hush panel on the passenger side. You'll be laying on your back on the floor and then you'll be able to see everything you need to move out of the way under the dash. The heater core cover is the tricky part to remove. It's held on by about 6-8 bolts. Remove the lowest cover bolts you can see and reach and then wiggle the cover back and forth to break the remaining top hidden bolt holes open. They're impossible to see and unscrew. No one will ever see them again and you really do not need ALL those bolts to hold the cover back on. NO NEED TO REMOVE THE DASH OR CONSOLE! I completed this job with simple tools in about 8 hours. Good luck!
Last edited by FOURSPEEDVETTE; Sep 24, 2024 at 06:19 PM. Reason: typo
Advanced
Joined: Jun 2024
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