The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board > The 1973 - 1991 Blazers, Jimmys, and Suburbans Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 02-05-2012, 03:25 PM   #1
Stringer
Registered User
 
Join Date: Sep 2010
Location: Kerrville, TX
Posts: 87
90 Burb....fan blows only @ floor

Need more hand-holding, please. Been reading old posts but it's not sinking in, I guess.

Got air and heat but it only blows out the floor vent. It'd be nice to have defrost, etc.! I know the plastic door pull is broken but the cable doesn't have any movement anyway. I mean - moving the selector switch does nothing. I don't hear any actuators actuatin' - no clicking under the dash. Is this most likely a vac problem? Any other thoughts?

finally - new CD - 2-7-12
Attached Images
 
Stringer is offline   Reply With Quote
Old 02-05-2012, 03:32 PM   #2
kwin
Registered User
 
kwin's Avatar
 
Join Date: May 2011
Location: Grande Prairie, Alberta
Posts: 368
Re: 90 Burb....fan blows only @ floor

I have had this problem with some of the Fords in the fleet that I manage, it seems to come down to actuator motors ( vacuum motors in your case ) or jammed flaps. For the new fords it's a $2000.00+ repair!

I know thats not much to work with but i think you are on the right track.
kwin is offline   Reply With Quote
Old 02-05-2012, 07:36 PM   #3
68Timber
I know the pieces fit
 
68Timber's Avatar
 
Join Date: Nov 2007
Location: MONTGOMERY, AL
Posts: 5,523
Re: 90 Burb....fan blows only @ floor

The switch does fail. If you don't hear it moving air when you move the switch then make sure it is getting vacuum.
__________________
John

79 2wd Blazer (Bruiser)
85 M1009 Blazer (Sarge) build
74 Honda Z50 build
68Timber is offline   Reply With Quote
Old 02-08-2012, 06:39 PM   #4
motornut
78K & 79C Jimmys
 
motornut's Avatar
 
Join Date: Nov 2009
Location: Ottawa Ont CANADA
Posts: 7,901
Re: 90 Burb....fan blows only @ floor

check here too,from my 88
Attached Images
  
__________________
John
1978 GMCJimmy4X4-350/203
1979 GMCJimmy4X2-305/350
motornut is offline   Reply With Quote
Old 02-08-2012, 06:59 PM   #5
Stringer
Registered User
 
Join Date: Sep 2010
Location: Kerrville, TX
Posts: 87
Re: 90 Burb....fan blows only @ floor

Thanks. I bet defrost in Ottawa is more essential than in North Texas but it's still a PITA not having it. Anybody know of a way to test the actuators-the round thing the vac line is hooked to?
Stringer is offline   Reply With Quote
Old 02-08-2012, 07:49 PM   #6
motornut
78K & 79C Jimmys
 
motornut's Avatar
 
Join Date: Nov 2009
Location: Ottawa Ont CANADA
Posts: 7,901
Re: 90 Burb....fan blows only @ floor

haha can't start the day without it lol
blow and suck......cheap n ez lol
i've used the washer/wiper hose to check them
Attached Images
  
__________________
John
1978 GMCJimmy4X4-350/203
1979 GMCJimmy4X2-305/350

Last edited by motornut; 02-08-2012 at 07:55 PM.
motornut is offline   Reply With Quote
Old 02-13-2012, 07:15 PM   #7
Jonboy
Slots go on anything!
 
Join Date: May 2003
Location: Richardson, TX
Posts: 5,957
Re: 90 Burb....fan blows only @ floor

If that clip doesn't fix it, the vacuum switch on the back of the A/C control head may be the culprit. They are prone to going bad, too.
__________________
1974 Jimmy- 5.3/4L80e/NP241
Jonboy is offline   Reply With Quote
Old 02-13-2012, 08:18 PM   #8
Stringer
Registered User
 
Join Date: Sep 2010
Location: Kerrville, TX
Posts: 87
Re: 90 Burb....fan blows only @ floor

Thanks to everybody for the help. I think I've got it fixed as of yesterday. A: broken vacuum line under hood. B: broken clip on the blend door. I artfully crafted a Copenhagen lid to take care of that. Next project is getting some lights to work behind the gas gauge. Thanks again.
Attached Images
 
Stringer is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 05:25 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com