It seems my axle for the floor heat door/flap is broken. Have serched a bit and found this tread:
https://blazerforum.com/forum/2nd-generation-s-series-1995-2005-tech-41/98-blazer-no-floor-heat-17808/

I just dont like the idea about sawing it apart for gaining access to the axle with the flap.
Anybody who knows how much of the dash that has to come out to remove the heater "box"
Thanks!!

 

just did this to replace the heater core on my 04 blazer.....its a real pain in the a**. Also there is not much help to be found.

there is about 100 or so screws and bolts to remove to get to the box that is attached to the firewall on the inside of the truck.

1. remove lower pannels under the dash (3 of them)
2. remove pannel under steering wheel >you will have to remove the parking break cable it disconnects rather easy<
3.remove glove box
4 remove defroster vent and remove the 4 or 5 screws up there
5. remove speaker grills on dash. there is 1 or 2 in each speaker location also
6. remove dash cover two screws on either side of the s. wheel and one right above the gauges the rest should be clips 4x4 buttons and rear window and hatch need to be disconnected
7. disconnect the radio and hvac controls and the connections for the air bag
"this is a good time to take the gauges out and clean them while you got it open"
8. remove the "L" brackets on both side of the steering column
9.there is a main connection for all the wireing on the passenger side that need to be undone
10. there is main bolts that hold the dash into the truck one on the driver side and 1 or 2 on the passenger side. once you remove these the dash should tilt forward and up and out...you will have to put the truck in 1st gear if its an auto to remove some of this stuff the gear shifter will be in your way

then you will see the box don't know if that would be far enough to reach what you need.. if not there is a few bolts holding it on to the fire wall one on the passenger side inside the truck and 4 on the outside of the fire wall.

2 of the bolts i had to remove the inner wheel well to get to them. so you gotta remove anything attached to it >overflow, computer, battery tray<

one is inside the box where the evap. coil is and another next to the heater core hoses


im sure i missed something so good luck...by the way i now haveing some issues with some of the stuff on my dash...you can find a thread in lighting and electrical


i would replace the heater core while in there unless you are confident yours will hold up

ps there is some connectors that have to come undone all over the dash one i failed to mention is the light switches and a main power connection over there also

 

See my new post on the link you have already. Hope it helps.

https://blazerforum.com/forum/showthread.php?t=17808

 

yeah. i think im going to put this off for awhile sinc emine still blows i cant control it but.ill wait.......till the summer maybe

 

winters are long and cold. if you have a warm garage to work in, then I would recommend the above link. it's a pretty easy job to do. that's if your flap is broken. you could have something else going on. Could be a vacuum issue. if you don't have a garage, then I would probably postpone it.

 

Thank u all for answers!

I have to say that I cind of liked gnpower`s idea a lot!! At first I didnt want to saw the heater box, due to the problems a cut would cause the flap`s axle to possible bond. But as gnpower shows, its possible to accsess the flap trough the front of the heater box. Brilliant. I`m going for that solution myself. I think I`m going to use a FEIN saw though. Theyre exelent for that kind of jobs.
In addition to fix the flap I`m going to modify the actuator so the sucker wont break again. I`m thinking of make the hole on the actuators metal rod elongated, like a slit. (sorry my bad english.....I`m Norwegian) That way the actuator wont put any stress to the axle when its in open position.
Anyway, does somebody have the GM part number for the heater flap axle, or does it come with the flap as one piece? I cant find it on rockauto.com
Thanks again!!

 

The part I used was p/n 15-50554 from www.oehq.com (defroster valve)

 

Well, I havent done anything yet. Its close to -17 C (1,5 F) outside so I`m not to keen starting the repair! I`m thinking about cutting a slit in the acuator, and make up a spring loaded mechanism which will relieve tension on the flap when its in "all floor" mode. I`ll try my idea out, and post some picture of it, if its a sucess. Thanks for all the answers!!

 

Hey there,...I got a 98 Blazer, I'm having the same problem,..my heater works but wont blow out on the floor, i swith it to the floor setting and it'll blow out the vents or defrost. What wound up working for you?
Thanks

 

Hi jdepew

Actually, I bought a Tahoe............
Havent done anything with the Blazer yet, but will go for sawing the heater box up front. Dont like the idea of sawing the heater box where the flap exits to the actuator. Still tinkering about an idea of spring loading the actuator to relief the flap from the stress it takes. I will look at the problem in a month or so, since I`m thinking of selling the blazer. If I find a solution I`ll post you some pictures.
Good luck!