Heater Core Replacement (Non-Air)

[curtmacd]

I've been reading about replacing the heater core on my 78 Cherokee, no a/c with the 258.

It looks pretty straight forward, but it appears that I need to remove two nuts under the dash and two nuts in the engine compartment to remove the assembly so I can split it to replace the core? Can someone verify this process?

[tgreese]

That sounds right. I've done this to one of my trucks, though I can't recall which now. Not difficult. The typical obstacle is the nuts under the dash, which are usually blocked by the A/C.

[Stuka]

I have done this on a 75 and an 81, both were pretty similar. The ones under the dash on my '81 were pain because it has A/C, so there was stuff in the way. On the '75 it was pretty easy.

Once you have the box out, it comes apart (clamshell like) and the core is just sitting in there as I recall. You may also find it has leaves and debris in there.

[curtmacd]

Thanks guys! Got it done, really easy. I found a cut in the vacuum line just as it passes through the firewall by the fuse box. I replaced the entire vacuum line and have vacuum to the switch now. Both actuators work good and select perfectly. I also adjusted the turnbuckle in the cool/heat cable to seat the door perfectly in both directions. Great heat and defrost now!

[Stuka]

Good to hear