1986 heater core
Thread Starter
Navigator
Joined: Aug 2004
Posts: 9
Likes: 0
1986 heater core
My heater core is leaking in my 86 coupe and I have a guy that is going to fix it for me,but I remember seeing a thread on here awhile back that had the EASIER way to change it by taking the passenger seat out and not removing the dash,but I can't find it.Any help would be GREATLY appreciated.
Burning Brakes
Joined: Aug 2004
Posts: 1,174
Likes: 125
From: Dunstable MA
St. Jude Donor '05
Replaced the core in my 87 recently and removed the seat because I thought there was going to be some upside down time involved. There wasn't. The top of the dash is easy to remove, and you will need as many angles of access as you can make, so I advise removing both the seat and the top of the dash. give yourself plenty of light; with the seat out you can set up a worklight in the rear deck area. If you have a lift, I think it will help your back if the car is a foot or so in the air. It also may help to remove the roof panel. I know I was constantly swinging my head into and out of the car trying to get a better fix on what I was trying to reach. In the Helms it says to remove the heater box door controller before the ECM. It is easier if you remove the ECM first and replace the door controller first on the reassembly. Just my take on it. Others may have better ideas. Good Luck.
Le Mans Master
Joined: Jun 2002
Posts: 6,097
Likes: 0
From: High Plains Drifter Fayetteville, AR
Make sure you use a Delco replacement. I used a cheaper one from autozone and had to replace that one shortly after. This isn't a job you want to do twice.
You'll have to remove:
Passenger seat
Dash pad
Dash trim
under dash trim
passenger crash pad
ecm
under dash brace on passenger side
air conditioning ducting under passenger dash
heater control door
and you'll have to move a portion of the wiring harness under the dash.
First time it took me around 10 hrs. Second time I was in and out in 6. I don't wish to ever do that project again.
You'll have to remove:
Passenger seat
Dash pad
Dash trim
under dash trim
passenger crash pad
ecm
under dash brace on passenger side
air conditioning ducting under passenger dash
heater control door
and you'll have to move a portion of the wiring harness under the dash.
First time it took me around 10 hrs. Second time I was in and out in 6. I don't wish to ever do that project again.
Burning Brakes
Joined: Oct 1999
Posts: 843
Likes: 2
From: Nashua New Hampshire
Originally Posted by Blaines86
My heater core is leaking in my 86 coupe and I have a guy that is going to fix it for me,but I remember seeing a thread on here awhile back that had the EASIER way to change it by taking the passenger seat out and not removing the dash,but I can't find it.Any help would be GREATLY appreciated.
Opening up the dash underside
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6th Gear
Joined: Mar 2013
Posts: 6
Likes: 0
Thanks for the tips and the pictures i am getting ready to replace the heater core in my 86 in the next few days and this will help a lot... it has been awhile since i have done this kind of work so all tips are needed....lol
again thanks
again thanks
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
I pulled the heater core out of my 85 today. I did not remove the dash pad. There was one screw on the top of the heater core cover that was a real pain to reach. I bought a 6" flexible 1/4" extension coupled to a 3" extension to get at it. I did remove the seat. The extra room to work was well worth the 4 bolts. I spent most of the day just getting it out. Tomorrow I have to get it back in. This is not a job I ever want to do again.
Team Owner
Joined: Jan 2003
Posts: 20,253
Likes: 220
From: Summerland B.C. Canada
Since I have tackled the core since this ancient thread was started, I'll add this link to a thread that I added a few pics to. 
rich 1st, you may find them useful
http://forums.corvetteforum.com/c4-t...ol-delima.html
rich 1st, you may find them useful
http://forums.corvetteforum.com/c4-t...ol-delima.html
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Since I have tackled the core since this ancient thread was started, I'll add this link to a thread that I added a few pics to.
rich 1st, you may find them useful
http://forums.corvetteforum.com/c4-t...ol-delima.html
rich 1st, you may find them useful
http://forums.corvetteforum.com/c4-t...ol-delima.html
Burning Brakes
Joined: Oct 2010
Posts: 1,037
Likes: 28
From: Montclair New Jersey
Whoever wrote that huge "pull the dash out" article was a friggin' crackhead.
You don't pull the dash, instead, pull the passenger seat.
Pull the hush panel, drop the ECM and the door control module.
Remove the support bar going from the door pillar to the dash.
Use a 7mm to take the cover off the heater box.
Pull the cover, unbolt the core, re-install.
Drink beer and laugh at webpage showing guys pulling dash.
By Fastguy
Perfect!
You don't pull the dash, instead, pull the passenger seat.
Pull the hush panel, drop the ECM and the door control module.
Remove the support bar going from the door pillar to the dash.
Use a 7mm to take the cover off the heater box.
Pull the cover, unbolt the core, re-install.
Drink beer and laugh at webpage showing guys pulling dash.
By Fastguy
Perfect!
6th Gear
Joined: Mar 2013
Posts: 6
Likes: 0
well it done thanks for all the good advice on replacing the heater core in my 86 vette it was not bad at all too a total of about 4.5 hrs but the was also replacing the heater hoses and thermostat
again thanks for all the help
Richard
again thanks for all the help
Richard
