Changing Heater Core

[Hutch]

The kid accross the street from me has a Grand Marquee. His heater core went out. Now that it's freezing here in Columbus Ohio he wants to have it fixed. Local shops want more than $400. So I told him we could probably do it as I did one earlier on my 1990 Mustang GT.

Bought a Haynes book. Looks like the heater core is in the dash similar to my Mustang.

Does anyone that has done this them selves have any hints or ideas to make this easier for me? Like hidden screws that I might not see, etc....

I believe the year of his car is 1984.

Thanks,
Hutch
hutchison_mark@hotmail.com

[grandpaslincoln]

This post may be dissapointing, because I don't personally have the answers for you. But, there a more than a few people here that have done heater core swaps, they just ain't online right now. Beleive me, this evening you will have more than a few posts in here on what to do.

But, buying a Haynes manual is a good first step.


Good luck man.

[Grand Marquis GT]

Welcome, hutch!

I made a stocky bout changing a heater core, and another couple postsabout it was wwell...theres a biit of info here and there...

But I havent done it myself..wish i could help out more...

[marquisman]

i ve done a heatercore in my 81' marquis and its not hard jus time consuming. first off u got to take the glove box off, that way you have some access around stuff. the next thing i did was take the main dash support from the bottom out abit by taking the one bolt out on the passengerside. next thing i did was disconnect the hoses and took out all the nuts and bolts and drop the box wit the core and take out the core bolts and it came out. it was a bit of a bitch to wiggle the thing out but, its possible, lol. hope this is some help. if u need more info, jus ask!

good luck!

[Ifixyawata]

From the looks of things it's very similar to the work you have to do in a fox chassis car (e.g. your mustang). I've done 4 fox cars and I'd have no hesitations about attempting a Grand Marquis. (Though I thank god the heater in mine is ok.)

[Hutch]

Thanks for the tips/replys.....

I'm actually hoping it's easier than my Mustang. But if they are both built on the fox body chassis it probably all pretty much the same.

Thanks again...

Hutch

[monterey1962]

$400?!

Local radiator shop around here did mine about two years ago for $130.

---------------------
Justin

[NitroNic]

Did everyone forget about this thread? :

http://grandmarq.net/forum/viewtopic.php?t=141&sid=978405fd2d4d4348b180bc46106ed4fb

Read that, Hutch, there are some good tips in there. THe main thing that makes it difficult, from what I remember, is pulling the whole dash panel back. If you have two people, it's easier... We've changed mine a few times (dad and I), and one of us usually pulls back on the dash, while the other pulls back on the heater core enough to let the pipes clear the holes, and then roll the plenum 180° forward (clockwise, if you're looking in at it from the passenger side of the vehicle).

It's also a good idea to make sure there is little or no coolant left in the heater core BEFORE removing it, otherwise you're likeley to have a mess on your interior. I suggest removeing hoses (then clamp them off, or plug them, or hold them up high so nothing else comes out), and then using an air compressor to blow the coolant out of the heater core. BUt don't have it at really high pressure, or you'll probably make another mess. ANd since you're changing the heater core, I"m going to assume that there is a LEAK in it, so it couldn't hurt to have a bowl, or newspaper, or something on your interior to put under the plenum, in case some coolant drips out upon removal, or upon blowing air into the heater core.

Whew.

[grandpaslincoln]

Woah! I forgot completely about that. And its right there in front of my face! Good job man.

[NitroNic]

Any time, Mr. Trump! :cool:

I just remember replying about 3 or 4 times in that thread, that's the only reason I remembered about it.

[86VickyLX]

It does not show up for me.

[86VickyLX]

That's right! Heater core removal time!!!

[mrltd]

It's a friggin 2 year old post MAN!

[86VickyLX]

So what? It should still be there. I need the easiest way to remove that heater core!

[85crownHPP]

nothing wrong with bumping an old thread for a good reason!!!

did you find the thread?

[86VickyLX]

No sir.

[85crownHPP]

hhmm... heres an "it was easy" how-to...

http://www.grandmarq.net/vb/showthread.php?t=84&highlight=heatercore

a more detailed account

http://www.grandmarq.net/vb/showthread.php?t=13054

[86VickyLX]

Thank you very much!!!!!!

[91LTDProject]

As our shop foreman says "ford hung the heatercore on a string inthose things and built the rest of the car around it" I'm waiting for mine to explode at the track one day. Its the last part of the cooling system I havnt replaced. Have fun and good luck

[grandpaslincoln]

Mines starting to leak, gonna tackle it this weekend. I was also going to do a tech writeup, but it looks like it's covered already.

[86VickyLX]

If you have an alternate way to do it please do it. It may be easier.

[gadget73]

we're already doing it the alternative way. Factory manual says to remove the air plenum and pull the whole thing from under the dash. I've never done this, but I know how that plenum is attatched in there, and it looks like a real disaster. Lots of vacuum lines to pull and other stuff. That, and it involves laying on the floor of the car for a long period of time.

[grandpaslincoln]

My manual says you have to disassemble the entire car in order to get to the heater core, I never knew of this alternative way. Does it still include taking the whole car apart? lol

[Lincolnmania]

much easier way
unbolt steering column, disconect gear indicator....lay on seat
remove dash pad, kick panels, pillar panels, disconnect speedo cable
unbolt lower dash support bolts, unbolt heater box, remove rest of the screws holding the dash......lay the dash on your lap, pull the heater box out a little and change the heater core and reassemble.

[87_crown_vic]

hmmmmm...when you come out this way for my engine you can get some heater cores and also install a heater core in Baby

[Mr. Land Yacht]

oh, heater cores in these cars are no fun at all
I had my uncle do mine...most of the interior(dash/steering column) had to be removed...but he's a pro, he did a great job.

our Mark V was really easy..he did that too...just open the hood and its right there...he had it done in like 20mins...he said it was the easiest he'd ever done....now I wish I had a Mark V.....wait...I do have one...its my dad's but I take care of it most of the time. :D

[gadget73]

The old cars like the Torino and similar are cake, just unscrew a plate and there you go. Shame they aren't still that way, then nobody would care about the core failing.