heater core?

sccrewzer

Registered User
My heater core went out yesterday night I was looking through the book to see if its difficult to change it seems like alot of work. My question is it neccasery to relieve the AC systems pressure or can it be done with out the step?
 
What year?

I think only the '94/'95 need to have the AC discharged...what does your book say?

You realize you'll get yes and no answers either way, right? ;)
 
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What year?

I think only the '94/'95 need to have the AC discharged...what does your book say?

You realize you'll get yes and no answers either way, right? ;)

It's a 92 the books says to discharge it but I can't see teh reason for that.

<There is no need to evacuate the AC system to R&R the heater core on any year/engine MN12.>

Thanks for info i'm gonna try it without disconnecting the AC.
 
Here's the factors involved:

The heater core can be extracted from the evaporator case without removing the case from the firewall.. however.. its a tight fit and you'll rip the foam seals up some. If instead, you decide to remove the case and split it open to remove the heater core, then you'll have to discharge the A/C and disconnect the hoses at the evaporator.

If you split the case, you'll need a good epoxy to reseal it.

If your A/C is working well, I'd suggest you leave it alone and just pry the heater core out.. There is a big block of foam that seals the tubes poking through the firewall.. bend the tubes towards each other and it should come off easily. :cool:
 
Back from the dead post

Well put off doing this for a few years :eek: cause i was kinda intimated by what i read and heard but sense i had four days off from work this thanksgiving week if figured what the hay plus it sucks driving with a fogged up windsheild.
After it was said and done i didn't know why it took me so long to start this job it only took me about 5.5 hrs. to complete and thats including the drive to the parts store to get the heater core and fixing my speedometer gears:D
keep in mind that this is my first heater core job so it's not that bad of a job so to those that wanna tackle this job go for it it's easy use the seach feature on this site it helps abunch
 
It really is one of those things where after you do it once, you can cut the time way down the next time. I think the first time, I spent ~4 hours from draining the coolant to reconnecting the hoses. The last time it was just under 2 hours.
 
As a note - since the car IS 21 years old (build date of August 1990), I'll be replacing the evaporator and all the inner foam also while the box is out.

That's a consideration, you know. Worth thinking about, anyway.

I may pick up the heater box from the boneyard and rebuild it before I tear into the car, so I have less chance of being down (since it's my ONLY car right now - and going into winter, no heat sucks.)

RwP
 
I may pick up the heater box from the boneyard and rebuild it before I tear into the car, so I have less chance of being down (since it's my ONLY car right now - and going into winter, no heat sucks.)
Only 1 running Supercoupe? Thats sad Ralph.. very sad. How do you make it day to day? Everyone should keep at least 2 of their SCs running while working their 3rd, 4th, etc. ;) :D

On the evap side, having done A/C work on my flock many times and pulled dashes more times than I can count, I would advise this... If you have a good working A/C... don't open it up :cool:
 
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Only 1 running Supercoupe? Thats sad Ralph.. very sad. How do you make it day to day? Everyone should keep at least 2 of their SCs running while working their 3rd, 4th, etc. ;) :D

On the evap side, having done A/C work on my flock many times and pulled dashes more times than I can count, I would advise this... If you have a good working A/C... don't open it up :cool:

It's worse - it's not even a SuperCoupe, but a 1991 XR7 with the 5.0HO!

I'm a poor working man, can't afford but one car right now. At least I have a great car to drive :cool::cool:

And currently, no, it doesn't work - the pressure is down to about 15PSI over atmospheric (slow leak somewhere), and I have a short to ground in the wiring to the A/C clutch. Both are due to be fixed at the same time.

I MAY see if someone around here can adapt the 5.0HO suction hose to match the V6 accumulator - for the 5.0HO, it's a one-piece assembly, and MAN it sucks buying that every time the A/C needs to be worked on!

RwP
 
MAN it sucks buying that every time the A/C needs to be worked on!
You need the source.. A/Ckits.com. I know.. chinese.. but they're cheap and AFAIK, dessicant is dessicant inside a sealed aluminum can. Of course, IMO, if its been sealed and it is only opened up briefly.. whats a few air molecules between friends.. :D I cap it off while working on other parts and then use a vac pump to dry it out.

I have heard of people baking them on low heat to revive them, but don't know how well it really works. :)
 
You need the source.. A/Ckits.com. I know.. chinese.. but they're cheap and AFAIK, dessicant is dessicant inside a sealed aluminum can. Of course, IMO, if its been sealed and it is only opened up briefly.. whats a few air molecules between friends.. :D I cap it off while working on other parts and then use a vac pump to dry it out.

I have heard of people baking them on low heat to revive them, but don't know how well it really works. :)

Yah.

I live in Louisana. We have > 90% RH days pretty darn often here. Dessicant sees where it is, screams in terror and dies within seconds :eek::eek:

I took a look there. They show the V6 accumulator, but no hose to match it. The accumulator below it? Look at the price difference.

http://www.ackits.com/merchant.mvc?Screen=CTGY&Store_Code=01&Category_Code=Mercury91Cougar_5-0

Ouch. BTW - I pay about that at RockAuto. Wait, no I don't, I take the 5% discount :D

RwP
 
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