My 1975 f150 has pooey brakes....they feel soft and feel like most of the braking is being done by the backs (back brakes lock easy, front doesnt dip when u brake hard)
Everything except the proportioning valve and the front calipers has been replaced, is it safe for me to assume its the valve?
Also questions that dont deserve their own thread thread.
Evan Young
Have all the steel hard lines been replaced?
Leo Ortiz
Only rubber, no leaks in the steel lines and they were flushed out. I get pressure front and back.
Noah Allen
I'm dealing with the same problem with my '86 F250. Feels like I have no power brakes, its all mechanical and I have to step on them to stop at all. But some times the pedal goes to the floor, other times it's as stiff and hard as can be.
Mine may be vacuum related cause diesel tho. who knows
Carson Gutierrez
>front calipers Does that old thing actually have disc brakes?
Jose Clark
Yes. Most 70s autos do.
The lighter weight trucks could be optioned with all drum though.
Asher Brooks
How old is the Master cylinder? Is it a single or dual master cylinder? I would suspect that before a proportioning valve.
Liam White
Its new and i replaced the old _also new one under this suspicion)
Jaxon Sullivan
Its dual chamber
Elijah Brooks
Could be booster. Pull hose and see if its wet with brake fluid, unless its hydro. The, i dont know. Also sounds like a bad master.
Cooper Long
If you have access to a power bleeder I would use that to make absolutely sure all the air is out of the MC.
Austin Green
Have you checked to see if the calipers are moving freely? Pistons and slide pins?
Have you bled out the fluid and renewed it?
Dylan Stewart
Its been bled but not flushed. One caliper seemed like it might be sticky but other is fine..
Brandon Garcia
Dont got, i bench bled it though.
Tyler Scott
Is it pulling to the side under harsh braking on the side with the suspect caliper?
Probably worth pipping it off and freeing up the slide pins and repacking them with high temp grease, do it on both, you'll probably find the pins are pitted and corroded.
Change the fluid and free that suspect caliper, clean the pad wells on the caliper carrier too and copper grease the contact areas of the pads.
Jonathan Anderson
You said you replaced parts, are they all correct and matched up? Make sure your master is the right size for your calipers
Caleb Lee
No, it actually isnt. If you'll read my original post it describes the way they act.
Ryder Brown
Are there any good comprehensive books on learning how auto engines work or how to diagnose and repair them?
Would buying said books along with a
Luis Jones
Yes, they are correct.
Noah Bailey
If you have the money....a chiltons manual and a old car works fine.
Jack Adams
Also these calipers don't have slide pins. Its a one piece caliper.
Luke Wilson
maybe ur fuckin cars broken bud
Noah Walker
yes and another thousand for a comprehensive set of amateur tools
David Gomez
The internal rod on the proportioning valve may have moved or be stuck. Their should be a small to push a little to reset its position. or it might be jammed with shit and stuck.
Anthony Wood
Maybe i just told you to read my previous post for symptoms instead of making needless wasteful ones like these "bud"
Grayson Harris
...
Liam Collins
Are your drums adjusted? No trapped air in lines?
Cooper Johnson
Thank you, I will check that.
Thomas Phillips
Yes, and as far as i can tell also yes.
Connor Thompson
Could be collapsed front hoses not letting enough fluid flow. It's rare, but I've seen it. Unless they're relatively new?
Ethan Martinez
They are brand new.
Also to everyone else i tried pulling the pin to rest the valve and it appears seized so i guess i have my answer.