I guess I'm just a 56 year old idiot. I am installing a complete interior in my 88 coupe. Thought since I had it all tore down I would replace the heater core as I have 140,000 mile on the car and it could go at any time. All of the manuals have me tearing apart the drivers side of the vehicle when the heater core and ECM are on the passenger side. I've removed everything they say on the drivers side and am now totally confused. Can anyone shed some light on this ? Any comments would be greatly appreciated.

 

I think you will find that some of the brackets that could get in the way are cross bolted... so the whole damned thing comes apart.

The instructions for removing the heater core should simply read: "Take car apart, remove core, replace core, reassemble car."

It's really a pain... I swear they build the car around the heater core.

 

If you like I can shoot a pic of the heater core R&R procedure in my '88 GM Shop Manual and e-mail to you. Just send me an e-mail at jgkov@msn.com and I'll respond.

BTW, it has no mention of going into the LH panel area aside from removing the inst panel.

 

I used the "fastguy method" (search the archives). Remove the passenger seat, hush panel, ecm, door motor, (don't break the white plastic clip), and support bar. The top bolt on the support bar is very difficult to get to. Its a 13mm bolt and I had to use a stubby wrench and then used a 1/2" ratchet with extension to turn the stubby wrench. (That bolt is in pretty tight and I couldn't get enough torque on it to losen it otherwise). I then removed 2 7mm screws that held some duct work on the front of the heater core box and disconnected the duct from an accordion style duct. Then I removed the 5 7mm screws holding on the cover. The top two were especially difficult to remove since they can't be seen. I had to sit on the ground and reach up on top of the cover. There is one on each side, you'll be able to touch them with a finger, but just barely. I just pretended I was blind and was eventually able to get a socket and extension on them. After the cover is off, you can see the core. It's held in with 2 7mm screws on the bottom. Remove the screws, disconnect the heater hoses in the engine compartment and pull out the core. You may have to cut the hoses if they've been on there a while. It took me 4 hours to get everything apart and 2 hours to get it back together. Now that I know what I'm doing, I'm sure I could do the whole job in about 4 hours, which is what the local mechanic quoted me for labor. He also said it'd come to about $350 total which is what gave me the courage to do it myself. I spent $70 on the core and about $30 on different size extensions, u-joints, etc. I didn't end up using all the tools I bought, but I like buying tools and I still saved $250. The job wasn't nearly as bad as I expected. Different years may be harder. It took me longer to replace my water pump or intake manifold gaskets.

 

Follow RondRed88's instructions and you won't have any problems. I did when I replaced the heater core in my '85. It's not as bad as everyone makes it out to be, just a very tight area to try to work in. The main thing is to remove the passenger seat and take your time. It took me two nights after work to get mine done. Also, don't try to cheap out on this part. Buy an AC Delco core. This is a job you don't want to do twice!

 

I didn't see it mentioned, but for me, I removed the dash pad and bread box too. In fact, I just kept taking off stuff until it was fairly easy to get at. Did find the white goop that GM used to seal the heater box to be fairly nasty stuff, so you might want to cover the carpet (if it's still installed) and keep some Goof Off and Simple Green handy. Other things to consider while it's all apart: - replace the Bose Amp Relay (if equipped) and the flashers (there's two - one for the turn signals and another for the 4 Ways) - reseal all the a/c duct work including the defroster (GM used foam -usually long gone and no longer available - but duct tape is better than nothing).

 

You gotta love this forum the experience here is just unblievable-and the help just keeps comming. to all the members.Another post to add to my book.

 

I replaced mine too, it was tough but not impossible. My problem is that I have these extra parts left over now and it doesn't seem to work properly without them. I have no idea where they are supposed to go, I don't even remember taking them out. They just appeared on the passenger floor. A flat metal piece and a plastic tube that is round on one end and square on the other. It's a winter project now.

 

This is one great forum ! Thanks for everyones help.I 'm glad this is a winter project so I don't need to be in any hurry. Also, wish I were 20 years younger. I could contort a little easier.

 

Take a lot of pictures so you know which pieces go where. The 7 mm screws have two different threads so notice which one go where when you taken those out.

 

Lots of good info in here; I've taken notes and hope to be prepared when my core goes.

 

I did as RonsRed88. I agree that the core is part number 1 and the car is built around it

 

I think that tube you are refering to is the supply tube for the defroster on the door sill.

 

Could be, thanks, do I need to take everything appart again?
Any idea what the metal plate is? From memory I think it is about 2"x3" and an irregular shape.

When I pulled the cover off it just fell out on the floor. I remember thinking this will be fun to put back in when I don't know where it came from .

 

The only metal plate I can think of over there is the prom cover on the ECM . Does it have a screw hole in the center on both ends?

 

It's not that one.
It fell to the ground when I removed the heater core cover. The ECM was sitting safely out of the way at this point.
It is not a rectangle but an irregular shape. Describing it is pointless. I will try to post a picture, but I'll start a new thread when I do.

Thanks