Go Back   Ford Truck Enthusiasts Forums > Older, Classic & Antique Trucks > 1987 - 1996 F150 & Larger F-Series Trucks
Sign in using an external account
Register Forgot Password?


1987 - 1996 F150 & Larger F-Series Trucks 1987 - 1996 Ford F-150, F-250, F-350 and larger pickups - including the 1997 heavy-duty F250/F350+ trucks

Welcome to Ford-Trucks Forums!
Welcome to Ford-Trucks.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Ford-Trucks Forums community today!





 
Reply
 
 
 
 
LinkBack Thread Tools Search this Thread
  #1  
Old 08-18-2014, 10:22 PM
Le Juggernaught Le Juggernaught is offline
New User
 
Join Date: Aug 2014
Location: Sacramento, CA (florin)
Posts: 10
Le Juggernaught is starting off with a positive reputation.
No Brake Boost on 1990 f250 xlt lariat gasser

So i just took over a title for my buddies 1990 f250 xlt lariat gasser thats been sitting in his back yard. I was inspecting the brakes and noticed the truck brakes work but only when it reaches the floor with no boost. Engine running or not there is not resistance to assist in braking. I did notice and air hissing leak sound coming from under the steering column in the cab as if a diaphram or seal had torn. My guess is if I had a blown seal or diaphram in the firewall mounted brake booster. I did bleed the brakes and saw no external brake fluid leaks coming from the lines, calipers or master cylinder. So my guess is a bad brake booster. Does anyone else have any advice or ideas what it could be and what should be replaced?
Reply With Quote
  #2  
Old 08-18-2014, 11:00 PM
UNTAMND's Avatar
UNTAMND UNTAMND is offline
Postmaster
 
Join Date: Jul 2009
Location: Lansdale, PA
Posts: 3,048
UNTAMND has a great reputation on FTE.UNTAMND has a great reputation on FTE.UNTAMND has a great reputation on FTE.UNTAMND has a great reputation on FTE.
Vacuum leak under the dash..... Do these trucks have a cruise control purge valve under the dash. You know, to let out vacuum from the vacuum servo to close the throttle.
As far as no assistance, booster must be bad. It's not unheard of. But check the hose and check valve to see if they are plugged.
If your brakes were good, assisted or not, the pedal shouldn't go to the floor. Double check for leaks, and maybe look for a swelling brake hose when you push the brakes. Possibly need to bleed brakes more or the master is also bad and not building pressure.
__________________
JR Strout..aim UNTAMND..00psd4x4ccsbLariet37sTwinTurbo
http://www.youtube.com/profile?user=untamnd#g/u
90 F150 xlt lariat supercab 4x4 long bed 5.8 auto red interior (stock for now) 61000miles
67 Mustang GTA Fastback 390 UNTAMND.com
Reply With Quote
  #3  
Old 08-18-2014, 11:09 PM
Le Juggernaught Le Juggernaught is offline
New User
 
Join Date: Aug 2014
Location: Sacramento, CA (florin)
Posts: 10
Le Juggernaught is starting off with a positive reputation.
ill check out the swelling hose. as far as the the leak under the dash it is only when i push down the brake pedal pushing the the rod through the cylinder causing a forced air release as if an o ring or seal has ripped and pushing it back out. almost as if its preventing it from applying the pressure it needs to activate the booster resulting in just applying the brakes mechanically. I hope I made sense somewhat.
Reply With Quote
  #4  
Old 08-18-2014, 11:10 PM
UNTAMND's Avatar
UNTAMND UNTAMND is offline
Postmaster
 
Join Date: Jul 2009
Location: Lansdale, PA
Posts: 3,048
UNTAMND has a great reputation on FTE.UNTAMND has a great reputation on FTE.UNTAMND has a great reputation on FTE.UNTAMND has a great reputation on FTE.
Yup. That also. Leaking booster you could probably hear inside cause of the gasket.
Check it out and let us know.
__________________
JR Strout..aim UNTAMND..00psd4x4ccsbLariet37sTwinTurbo
http://www.youtube.com/profile?user=untamnd#g/u
90 F150 xlt lariat supercab 4x4 long bed 5.8 auto red interior (stock for now) 61000miles
67 Mustang GTA Fastback 390 UNTAMND.com
Reply With Quote
  #5  
Old 08-18-2014, 11:20 PM
Le Juggernaught Le Juggernaught is offline
New User
 
Join Date: Aug 2014
Location: Sacramento, CA (florin)
Posts: 10
Le Juggernaught is starting off with a positive reputation.
will do. dont have time tonight but ill get back to you guys either tomorrow or wednsday
Reply With Quote
  #6  
Old 08-25-2014, 01:34 PM
Le Juggernaught Le Juggernaught is offline
New User
 
Join Date: Aug 2014
Location: Sacramento, CA (florin)
Posts: 10
Le Juggernaught is starting off with a positive reputation.
So i ended up replacing the brake booster and then also realized I needed to get new rotors and pads. But it still is not working as I had hoped, yet the braking is alot better. So my last thought is the master cylinder with an internal leak.
Reply With Quote
Old 08-25-2014, 01:34 PM
 
 
 
Reply

Go Back   Ford Truck Enthusiasts Forums > Older, Classic & Antique Trucks > 1987 - 1996 F150 & Larger F-Series Trucks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Remote brake booster question GB SISSON 1948 - 1956 F1, F100 & Larger F-Series Trucks 16 03-13-2014 09:12 PM
FORD F-250 Brake pedal sucked! Ford5.8XLT88 1987 - 1996 F150 & Larger F-Series Trucks 26 07-21-2011 04:29 PM
Need help with vacuum ladiabla74 1997 - 2003 F150 6 07-30-2008 09:03 PM
Vaccum leak under dash? danray35e 1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks 7 12-01-2006 01:04 AM
Brake Power Booster Trouble 75ford250 Aerostar 2 03-15-2004 01:25 AM



All times are GMT -5. The time now is 11:55 PM.


Powered by vBulletin® Version 3.8.7 AC1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Advertising - Terms of Use - Privacy Statement - Jobs
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.

vbulletin Admin Backup