Join Date: Nov 2008
Location: Port Orchard, Wash.
Wow... Small Jeep-world, isn't it? I'm the "Tim Taylor" that Terry Howe credits at the bottom of his how-to on the Blazer blower motor swap! Back in the Jeep-L days I had heard about this swap so tried it, then wrote some basic instructions. That was like 12 years ago! Then Chris Tucker and Terry did it and took pictures and did a really good job of writing it up.
My heater is out again in mine as I'm dealing with a lot of issues that need dealing with on my CJ. I'm going to crack my heater housing (plenum?) open and check the flaps in there. That might be part of the problem with your heater not working right. Those flaps that direct the air from hot/cold, fresh/recirc, floor/defrost have a rubberized outer edge that can dry out or tear. A friend of mine recently redid one using rubber from an old truck inner tube to freshen up those seals. I may end up doing something like that on my own.
Anyway, bottom line is, since you'd have to have your heater box out to do the Blazer blower motor swap anyway, check those seals.
But I'm telling you, replacing that blower motor makes a HUGE difference! The first time I turned that thing on, it blew old leaves out my defroster vents!
'04 Grand Cherokee