Installed a booster off a 73-79 in my 67 F250. The body is a donor and is installed on a 78 F250 4x4 chassis. I kept the original brake pedal and hanger system.

Stupid question of the day... but now that it's all together with new pads and bled.....when the brakes are depressed, they do not force the pedal up ( in other words the front brakes stay on ) you have to pull the pedal up the last 1/3 of the way by hand to get them to come off. Now the rotors are crap and the calipers are so so..not sure if that would have any adverse effects on the system. I thought maybe proportioning valve also a possibility as I was getting kinda crappy flow to the rears when bleeding ( and well it's only the fronts holding on when the pedal is "stuck"..but I also still need to adjust the rears so I think that point is moot)

Anyone ever encounter this? I've never seen / there should be no reason a brake pedal needing a "return spring" ( trying to imagine how wrong that would be...lol)

Give me some opinions for my situation

 

could be bad brake lines (the rubber ones) blocking the return flow of fluid. ive also had a caliper go bad and do the same thing.

 

My VW's had horrible problems with corrosion inside of the rubber lines.....to the point where only a trickle of fluid would flow to some drums.....I would advise you to replace ALL the rubber lines....they will break eventually, especially if they are old....You may then want to double check the compatability of your Master with Drums....it may have different output for Disc brakes.......then replace all those wheel cylinders, replace broken adjusters....and plan on spending the cash for shoes and drums.....they always need to be replaced when you have the least cash flow!

Good luck with the project!

 

Update time: Took the booster off today.. think that's it. Looks like the master has been leaking into the booster...and when push the rod from the back ( pedal side) it doesn't want to return all the way ( till you pull it like I was doing)....

So... I had a spare one off another 78 3/4 (this one is off a 2wd) they look a little different, but not overly so. The master on the spare has the lines coming out the other side( pass), and the bore looks smaller. SO..I will just head off to the parts place tomorrow and get a reman correct one. Also took the time to vacuum bleed the brakes completely removing all old fluid. I had just bled them, but the crap that came out was amazing. Also just in case crap got from the master to the proportioning valve, I also vacuum bled the backwards ( bottle of fluid on the nipples- sucking from the lines at the master. That produced some crap too. All nice and clean now... will re bleed after I throw on the new master and see how it goes.

No doubt, the calipers and wheel cylinders are next... I am sure given the condition of the master/booster...the other stuff is crap too.

Oh and I found the adjustment for the booster..it's on the rod on the master side. I will try and turn it in 8 turns so I can move my pedal down some inside too.( it's sky high, would be higher if I take the stop out too.) Would have been a nice idea to use the pedal and hanger off a 73-79 , but then it doesn’t bolt up to the dash the same way... oh well.

What's a little more money right ? When I get her bled I'll let you know how it went.. Thanks for the advice so far.

 

Well with new Rotors/Calipers and my spare used ( but good) booster.. I have perfectly functioning brakes !!! Whoo hoo... I am sure the booster was the big problem, calipers second. Still going to open the rears and see what's up there. Can't get a good bleed back there. ( the only parts I haven't changed yet- axle lines, hose and wheel cylinder.. which I guess will be next.

 

I had a weak booster on my F-100 and I was going to put a spring on the pedal to pull it up, when it totally went one day. I replaced it with a F-350 disc brake booster/master set up and it works great.