This past spring the heater core in my 77 was leaking, so I bought a NOS aftermarket heater core off ebay as a replacement. I pressure tested it on the bench before installation and everything looked fine, so I put it in. Unfortunately, joy was short lived and by the end of the summer, the new one that I just put in was leaking. Again.

Direct drop in cores are getting hard to find, and are expensive, so I started messing around with alternatives. I've been reluctant to mention it because the project isn't done and until the T's are dotted and the I's are crossed, there's the chance that something will come up that kills the whole idea.  However, I'm going to jump the gun a little and mention it here just in case other 260/280 owners are getting ready to drop cash on a new heater core.

Heater core for a 91-02 Ford Escort SOHC (not the ZX2). The heater core is aluminum, and the one I got was Spectra Premium P/N 94741.

So with the caveat that there is still the chance that I'll run into an insurmountable detail and this may not really work for some reason, here's a teaser of something I've been working on. The box is done and has been sitting on the bench for a couple of weeks. I'm going to pull my dash this off season to finish the work, but here is where I am right now. And I have no idea if this idea would even work for the 240's, but this is what I've got. Aluminum heater core for a Escort with a layer of foam around the outside for a snug fit:

Build a little shelf for the Escort core to sit on. Since the Escort core is a little thinner, it allowed me to move the core up a little so it doesn't interfere with the floor duct control linkages at the bottom of the heater box (like the stock one does). Aluminum angle material screwed into place as a lower support shelf:

Escort core in place before putting on the access panel cover. Can't see it in the pic, but it's resting on the new aluminum shelf on the far side:

With access cover in place and tubes poking through new holes I cut in the cover. Tape over the original holes so air doesn't come out where it's not supposed to. There's also another support shelf on the inside of the cover as well and if you look carefully, you can see the heads of the screws that hold the shelf in place:

I need to pull the dash to finish the project and figure out how to make the hoses work, but I'm confident I should be able to figure something out.

I'll post more pics of that process when I get the dash pulled.

Looks promising. 

I wanted ask you if you've read or seen someone putting a switchable valve in the engine bay that would bypass the core until cold weather? I'm almost positive I read where somebody did that in the past. I'm not using my laptop at the moment or I could search around. Any thoughts or have you heard of this? I'm pretty sure it was a 240 because those allow some hot air releasing in the cabin when you don't need any. Maybe it was an A/C thread?

I thought it never got cold in Alabama ...     

11 minutes ago, S30Driver said:

I thought it never got cold in Alabama ...     

I live in the North.  Under 50 & I stay inside eating chili and quietly (sometimes) farting.

 

51 minutes ago, siteunseen said:

I stay inside eating chili and quietly

And drinking beer with the chili?  

2 hours ago, Captain Obvious said:

Heater core for a 91-02 Ford Escort SOHC

Not a bad price either! Going to follow this thread.

Cool idea! (Inverse pun unintended)...

Nice idea!  When you have a chance, can you take a photo of the Escort core next to the original core?

Wow ... $36 shipped from Rock Auto

This could get hot if Captain O's project is successful.

4 hours ago, siteunseen said:

I wanted ask you if you've read or seen someone putting a switchable valve in the engine bay that would bypass the core until cold weather? 

Pretty sure that CO moved his coolant flow control valve to the engine bay.  To fix the off-on nature of the system when the capillary-controlled thermostat valve goes bad.  He could probably put together a pretty good system overhaul and improvement procedure.  

There may be some pressure with this project.  I think he can keep a level flow of good ideas though.

Yeah, the prices on this thing were great. And the workmanship looks pretty good too. One thing to watch for though is there are some of these are brass and some are aluminum like I pictured. The first one I got was the slightly smaller brass version and I sent it back to Rock Auto. They sent a second one and it's the one I wanted. I never completely got to the bottom of what happened though. I'm still not positive it was simply misboxed, or a different manufacturer in the Spectra box. I know many of the manufacturers will second source eachother with the intention that the parts are form / fit / and function interchangeable. They accepted the brass one back without a fuss though, and I got the aluminum one as pictured.

7 hours ago, Mike said:

can you take a photo of the Escort core next to the original core?

By your command. The length and width are very similar to the original. The biggest difference is the thickness. The Escort core is thinner:

To be honest, with a layer of 1/2 inch thick foam along the perimeter of the Escort core, I think it fits the heater box better than the original. Of course, my "original" is an aftermarket core that came with the car, but I was not impressed with the fit.