Heater core replacement for Mark X 1965

Maybe these help. They are a bit scary, so I’ll put the finished one first! Unfortunately, looks like I didn’t take photos of the new catch basin before I installed it. Keep in mind that my car has very little rust otherwise. The mk10 heater/scuttle is a major design flaw imo.


Toyjag, if you are lucky, your core may require only a repair, as did mine, which failed at the solder joint of the lower pipe. I’d take it out, then you will know what you are dealing with. If the basic core is sound, any good radiator shop should be able to do the job. If mine had not been repairable, and I had not found a suitable used item, I would have found a new core which could be modified to fit.

So its out without cam cover removing. Was rusted to car, so i poured it with antirust liquid, took off one fan to catch the heater core by hand tightly, release it with force and wooden stick under and behind the core, and after some time of wiggling, it went out (no need to mention lot of rude words :smiley: ). Car looks much better then expected, just surface rust, heater core need to be redone, bootom part and one brace are rusted through, but most of it can be used again, imo. Btw, im not sure how to remove inner flaps out without grinding the core?

With a core that big, and two blower motors, I bet that baby can really throw some heat in the Winter.
Now if someone could design a system to cool that bad boy, it would really be something for year round use.

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Good job. Glad to see that the center of the car is not too bad.
THe flaps are easy to remove. Look at the photos of the disassembled box on my earlier reply in this thread. Simply take the screw out of the locking arm of the pivot rod and it pulls out, allowing the flap to come out.

Ah, ok, easy, i got it. Thanks Ron!