Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

AC/Heater blower valve problem

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by BayouBlazer88, Oct 16, 2003.

  1. BayouBlazer88

    BayouBlazer88 1/2 ton status

    Joined:
    Jul 31, 2002
    Posts:
    353
    Likes Received:
    0
    Location:
    Lafayette, LA
    About a year ago the blower valve broke and it stayed stuck in "Bi-lev" meaning half of the air blows through the dash vents and half through the floor vents. It never was that much of an inconvenience so I just put it off. So this afternoon I pulled off the glove box and then took out the plastic duct to expose the valve. The plate was full of rust (naturally) and the part that was broken was the plastic peice that connects the metal rod to the plate. Now I'm not talking about the metal rod on top of the duct that is connected to the spring, but the one inside of the duct. Now what I don't understand is what rod opens and closes the valve when you change the AC selector to a different position, the one inside or on top of the duct? Becuase whenever I changed the AC selector to a different level, neither of the rods moved. Does the truck need to be running for the AC selector to open and close the valve? Also, where can I get a replacement plastic peice that connects the metal rod to the valve plate. Does LMC sell them? Or do I need to go to the dealer?
     
  2. fad2blk99

    fad2blk99 1/2 ton status

    Joined:
    Feb 19, 2001
    Posts:
    860
    Likes Received:
    0
    Location:
    Charleston, SC
    I'm not 100% sure which plastic piece you're talking about... is it the one that controls the flap/door inside the air distribution box? Its the only one I can think of at this moment... anyway, if my description sounds like the one, I had no luck finding one new, dealer, LMC or otherwise (These little plastic things were broken on both my previous '88 Blazer and now my current '89 Jimmy). I had to scour the junk yards to find one. It’s quite a bit of work for such a seemingly inconsequential little part, but at least my vents function properly now /forums/images/graemlins/thumb.gif

    Also, I'm not sure if the AC controls need engine vacuum or not to function properly, but just to rule it out I'd go ahead and start it up, provided your heater core lines are hooked up or hooked together in a bypass loop.
     
  3. BayouBlazer88

    BayouBlazer88 1/2 ton status

    Joined:
    Jul 31, 2002
    Posts:
    353
    Likes Received:
    0
    Location:
    Lafayette, LA
    The piece I'm talking about is the one that connects the flap door to the metal rod or beam inside the duct. It has one bolt that holds it to the flap door. So I guess we're talking about the same part. It looks like the only one succeptable to breakage. I'm sure I can rig up something. If I can't do that, I might just make something that keeps it blowing through the top always, since I never really have any reason to cool or heat the floor. Later on I might make a trip to the junkyard and see what I can find. I wonder if GM used the same system in the newer body-style trucks (88'-98'). Anyway, thanks for the help.
     

Share This Page