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Topic: Evaporator for Heater Core (Read 3012 times) previous topic - next topic

Evaporator for Heater Core

I am going to do yet another Heater Core Change...and yes I deserved this one. Anyways, the last time I did this I left the evaporator core (the rest of the AC has been removed) in the car in case I needed to use it as the Heater Core. Sounds crazy maybe, but if I put the proper connectors on the heater lines, and a flow control valve (VW,or old Mopar Style) it seems like it should work.

Tell me why this would be a bad idea before I try it.

Thanks,
Cooter

Evaporator for Heater Core

Reply #1
It may work,but changing the heater core isn't that bad.I used to think it was because I was going the long way of doing it.After reading the "right" way of doing it,it can be done in an hour or so,and,it'll be done the right way.Don't take short cuts.Plus,I don't know what those evaporators can take as far as water pressure and heat go.Why take chances when you can spend a little on a new heater core,do the job right,and have no worries about what "Might" happen.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Evaporator for Heater Core

Reply #2
Quote from: vinnietbird;291450
Why take chances when you can spend a little on a new heater core,do the job right,and have no worries about what "Might" happen.




yes. i dont know that it wont 'work' exactly but it wouldnt be right. they're not made to have any water in them at all, now thats all you have(with antifreeze). plus it just sounds like you would be opening up a can of worms doing that.
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

Evaporator for Heater Core

Reply #3
It has been done before by a couple of people on this board.
It makes your controls basackwards. You have to set them for cooling when you want heat.

Evaporator for Heater Core

Reply #4
Quote from: vinnietbird;291450
I don't know what those evaporators can take as far as water pressure and heat go..


When was the last time you looked in to A/c pressures? When was the last time you looked at your radiator cap rating? The A/C system operates at much greater pressures than you cooling system does. A/c 35-180psi and what does the rad cap hold to like 13-18 depending on application. So yes it will take the pressure and yes it will work.

Stuckman
84 Turbo coupe 2.3T Modded with 88 upper and lower intake, 88 injectors, E6 manifold, T3-4 AR.60 turbo, 31X12X3 FMIC, Homemade MBC , Greddy knock off BPV.
4 eyes see better than 2! 
Da Bird!

FreeBird

Evaporator for Heater Core

Reply #5
I am pretty sure the Evaporator Core can take higher pressures, I am not sure about the higher range heat cycles affecting it. I intend to do the change with a Motorcraft Core, and you're correct Vinnie, it isn't that bad at all (especially this time of year, not on the side of Interstate!). Last time I even swapped an entire HVAC Case without removing the IP from the car.

This post is here to help me make up my mind about leaving the Evaporator Core in (again) as a backup. I will be TSD-Rallying, RallyCrossing  and Ice Racing this car this Winter, and I intend to drive it to all events so this is a decision of whether or not to trust the Motorcraft Core with all of the impacts, Vibrations, and harsh conditions. (I am even considering buying two heater cores and mounting one in the old Evaporator location with an adapter.)

grutinator, I wonder about the passages in the Evaporator Core as far as flow, but most systems (including ours) have the refrigerant entering the Evaporator Core as a Liquid (it's not just a clever name). And I am pretty sure refrigerant is thinner and more corrosive that Coolant.

And Softtouch, this make sense. Our HVAC Boxes pull outside air, or inside air through the Evaporator Core First always. I could set it on MAX HEAT!!! Circulating In-Cabin air only! Do you recall the names of the people that did this?

Thanks for the replies guys, I'll think about this some more...

Evaporator for Heater Core

Reply #6
Thanks Stuckman! (Didn't see your post...) You're talking me into leaving it in there...

Evaporator for Heater Core

Reply #7
Quote from: CootersXR7;291509
Do you recall the names of the people that did this?

I am pretty sure jcassity did it. I can't remember the other one, but they were in a cold climate in winter.

Evaporator for Heater Core

Reply #8
Thanks softtouch, I'll dig around and see if I find or get some more comments from jcassity.

Thanks again,
Cooter

No more motorcraft cores?!?!

Reply #9
Plot Thickens. Motorcraft cores are apparently unavailable...(checked '93 Mustang as well)  Anyone's opinion different of what I should do now? Aftermarket gives a 1-year warranty only.

Evaporator for Heater Core

Reply #10
Quote from: ipsd;291507
When was the last time you looked in to A/c pressures? When was the last time you looked at your radiator cap rating? The A/C system operates at much greater pressures than you cooling system does. A/c 35-180psi and what does the rad cap hold to like 13-18 depending on application. So yes it will take the pressure and yes it will work.

Stuckman

You quoted me,then apparently didn't read what you commented on.I stated VERY clearly...."I DON'T KNOW" what the pressures and temp ratings are.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Evaporator for Heater Core

Reply #11
Quote from: CootersXR7;291529
Plot Thickens. Motorcraft cores are apparently unavailable...(checked '93 Mustang as well)  Anyone's opinion different of what I should do now? Aftermarket gives a 1-year warranty only.


I just checked Latemodelrestoration's website and they sell the original ford cores for $79.99. Part number is  LRS-18476AF.
[SIGPIC][/SIGPIC]http://www.fquick.com/slicksport88
88 Sport - 5.0HO, Mass Air, A9L, 73mm C&L meter, BBK CAI, 255 lph pump, 1.7 roller rockers,Professional Products damper, Chuck W motor mounts, BBK shorties & H-pipe, Flowmaster 40 series, 8.8 rear w/3.27's, 93 Cobra M/C, BAER 13in. drilled/slotted rotors front and back, cobra calipers, Russell braided brake lines front & back, C/C plates, 03cobra rims, 255/40/17 Nitto 555's all around

Evaporator for Heater Core

Reply #12
Thanks slicksport88, I'll check into this.

Evaporator for Heater Core

Reply #13
When doing the heater core replacement, make sure you get the heater hose that has the restrictor in it or you can buy the restrictor from LMS and install it in an aftermarket hose. It goes into the fatter one. What really kills a heater core (especially the cheap aftermarket ones) is handling of the rubber hoses that attaches to them. There is very little support from the tubes coming from the heater core and installing/removing the rubber hoses typically causes failure of the heater core.
Raleigh, NC.

Evaporator for Heater Core

Reply #14
Quote from: 04FordHarleyF250;291628
When doing the heater core replacement, make sure you get the heater hose that has the restrictor in it or you can buy the restrictor from LMS and install it in an aftermarket hose. It goes into the fatter one. What really kills a heater core (especially the cheap aftermarket ones) is handling of the rubber hoses that attaches to them. There is very little support from the tubes coming from the heater core and installing/removing the rubber hoses typically causes failure of the heater core.

Where can you get the heater hose with a restrictor in it?  I'd like to use one of those, but have a sneaking suspicion that my local auto parts stores wouldn't have a clue if I asked them for one.
William