Notices
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks Discuss the Early Eighties Bullnose Ford Truck

A/C won't blow

Thread Tools
 
Search this Thread
 
Old Aug 17, 2014 | 11:06 PM
  #1  
ramirezbrandonc's Avatar
ramirezbrandonc
Thread Starter
|
New User
Joined: Aug 2014
Posts: 3
Likes: 0
A/C won't blow

I am looking for a diagram of the air conditioning system of my 1985 F-250 XLT Lariat. I don't know if this matters, but it has a 351W H.O.

My blower motor is blowing, but I cannot get the vents to open. I don't know if this is the plenum, the vacuum, lines, or a switch. If anyone knows a way for me to troubleshoot this I would greatly appreciate the input. Also, if someone has any drawings, or knows where on the internet I can find some drawings, I would appreciate the information.
 
Reply
Old Aug 18, 2014 | 06:54 AM
  #2  
CountryBumkin's Avatar
CountryBumkin
Posting Guru
Joined: Apr 2011
Posts: 1,636
Likes: 5
From: Orlando area
Everything you need to know is in this thread: https://www.ford-trucks.com/forums/1...t-working.html
 
Reply
Old Aug 18, 2014 | 07:49 AM
  #3  
Gary Lewis's Avatar
Gary Lewis
FTE Legend
15 Year Member
Photogenic
Photoriffic
Shutterbug
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
CB - I would rep you if I could. Good job.

RBC - On all but the dealer-installed AC trucks vacuum is used to control the doors of the HVAC system. And dealer-install AC won't have the standard AC vents in the dash, so if you have the vents your system uses vacuum.

The default position for the system without vacuum is Defrost. So if yours is blowing air on the windshield you probably have a vacuum problem. But, I have seen pencils or other things that fall into the defrost vents jam the doors. So check it out and let us know.
 
Reply
Old Aug 18, 2014 | 08:22 AM
  #4  
NumberDummy's Avatar
NumberDummy
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 785
From: Simi Valley, CA
Club FTE Gold Member
Originally Posted by ramirezbrandonc
I am looking for a diagram of the air conditioning system of my 1985 F-250 XLT Lariat. I don't know if this matters, but it has a 351W H.O.

My blower motor is blowing, but I cannot get the vents to open. I don't know if this is the plenum chamber (aka A/C heater box), the vacuum lines, or a switch. If anyone knows a way for me to troubleshoot this I would greatly appreciate the input. Also, if someone has any drawings, or knows where on the internet I can find some drawings, I would appreciate the information.
E1AZ-19B888-B.. A/C Vacuum Control Selector Valve Assy (Motorcraft YH-380) / Obsolete ~ Dozens available NOS from Ford dealers & obsolete parts vendors.

Applications: 1983/89 F100/350 & Bronco / 1981/89 Crown Vic/Mercury Grand Marquis-all w/factory installed integral A/C.

This valve bolts to the back of the A/C/heater control panel (19980). All the vacuum lines connect to it, then route to the blend door motors (18A318A).

When you slide the lever on the control panel, this valve opens one door, closes another.

Besides this little charmer, one or more of the vacuum controlled blend door motors could be defective.
 
Attached Images   
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
dino360
Cooling, Heating, Ventilation & A/C
0
Jul 3, 2018 09:09 AM
TobyM
Excursion - King of SUVs
8
Nov 13, 2013 10:33 PM
Normspeed
1978 - 1996 Big Bronco
4
Dec 7, 2009 10:08 AM
78Ranger_GARedNeck
1973 - 1979 F-100 & Larger F-Series Trucks
4
Jan 12, 2009 06:13 PM
tombob
1978 - 1996 Big Bronco
2
Oct 11, 2004 01:13 PM




All times are GMT -5. The time now is 01:05 PM.

story-0
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-1
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 10:59:05


VIEW MORE
story-2
Rezvani's Latest Post-Apocalytic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-05-30 18:33:59


VIEW MORE
story-3
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-4
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE
story-5
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-6
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-7
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-8
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-9
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE