F100 brake issue
Thread Starter
|
New User
Joined: Oct 2012
Posts: 8
Likes: 0
F100 brake issue
thanks everyone in advance... I'm new to the forums, new truck. I bought a 1979 f-100 a couple days ago. Guy who was selling it had just installed new master cylinder but said he had not bled brakes.
brakes feel normal for one push, then get hard. if i wait a minute, normal for first push then hard.
I got it home, started to bleed brakes and no fluid from the rear passenger side bleed port. little from the rear driver side and lots of air. Fluid from fronts lots of air.
thought maybe the rears were not getting fluid. I checked at the T valve on the rear diff and got fluid from both sides of T valve. unscrewed the connection above the bleed ports on both sides and got fluid from both... lots of air from the passanger side. i took of the cylinder and made sure pin from the booster was making contact, adjusted it out a little bit. put the cyclinder back on. I re-bled the cylinder while on the truck.
went for test drive and pedal is still firm no softness... it isnt even soft on the first press anymore. at the end of test drive left front disc locks up starts smoking.
im thankful for any help!
brakes feel normal for one push, then get hard. if i wait a minute, normal for first push then hard.
I got it home, started to bleed brakes and no fluid from the rear passenger side bleed port. little from the rear driver side and lots of air. Fluid from fronts lots of air.
thought maybe the rears were not getting fluid. I checked at the T valve on the rear diff and got fluid from both sides of T valve. unscrewed the connection above the bleed ports on both sides and got fluid from both... lots of air from the passanger side. i took of the cylinder and made sure pin from the booster was making contact, adjusted it out a little bit. put the cyclinder back on. I re-bled the cylinder while on the truck.
went for test drive and pedal is still firm no softness... it isnt even soft on the first press anymore. at the end of test drive left front disc locks up starts smoking.
im thankful for any help!
Senior User
Joined: Oct 2012
Posts: 197
Likes: 0
From: Dublin CA
Can be a few things.. make sure the caliper slides are lubed and the calipers arent sticking. Old brake hoses can act like check valves. Not allowing hydraulic flow. Check rear brake shoes that they arent hanging up against the backing plate.
Thread Starter
|
New User
Joined: Oct 2012
Posts: 8
Likes: 0
I think my issue may have just been that caliper sticking... it would have caused the soft then firm and then soft again after rest. Finally froze up so now they are stuck firm. Going to replace and see.
Thread Starter
|
New User
Joined: Oct 2012
Posts: 8
Likes: 0
Thanks for the help.
Yep, the caliper fixed my hard brake pedal problem. I am still having an issue though, pedal is very soft now... pushes down to floor. No fluid leaks I can find. Not able to bleed breaks, just little drops of fluid come out.
The master cylinder is new.. but I guess it could be bad. Any thoughts?
Yep, the caliper fixed my hard brake pedal problem. I am still having an issue though, pedal is very soft now... pushes down to floor. No fluid leaks I can find. Not able to bleed breaks, just little drops of fluid come out.
The master cylinder is new.. but I guess it could be bad. Any thoughts?
Senior User
Joined: Mar 2004
Posts: 280
Likes: 2
From: Alabama
I highly recommend that you take your master cylinder off and bench bleed it again. I'd almost guarantee you will see air in the front part. I recently had the same issue (soft pedal) after replacing almost everything in the brake system. I made the mistake of bench bleeding the master cylinder on the truck and thought it was good but after taking it off after verifying everything else, it took me another 15 minutes to get it bled. Also, just verify the back brakes are adjusted right and don't assume. Just jack it up, put it in neutral, and spin the tire and listen for that slight drag.
Thread Starter
|
New User
Joined: Oct 2012
Posts: 8
Likes: 0
Trending Topics
Moderator & parts slinger
Joined: Feb 2007
Posts: 50,186
Likes: 5,792
From: S/W Missouri, Polk county
X 2 on the bench bleed, and then rebleed starting at the farthest once away.
Back R
Back L
Front R
Front L
Never let the m/s get empty when bleeding. You should have a good steady stream of brake fluid when bleeding the sys. New fluid in and bleed till new fluid out.
Back R
Back L
Front R
Front L
Never let the m/s get empty when bleeding. You should have a good steady stream of brake fluid when bleeding the sys. New fluid in and bleed till new fluid out.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
Thread Starter
|
New User
Joined: Oct 2012
Posts: 8
Likes: 0
bench bleed wasn't giving any pressure from the week old master cylinder. Took it back under warranty.
Popped new MC on today, bled it on the truck, bled brakes all around... brakes working perfectly. Thanks for all the help!
Popped new MC on today, bled it on the truck, bled brakes all around... brakes working perfectly. Thanks for all the help!
Thread
Thread Starter
Forum
Replies
Last Post
hevnbnd
1973 - 1979 F-100 & Larger F-Series Trucks
31
May 7, 2006 10:25 AM
icuhatn99
1973 - 1979 F-100 & Larger F-Series Trucks
6
Mar 20, 2006 10:23 PM