Brake Pedal Slow to return

[Ken B]

What could be the cause of the brake pedal slow to return while trying to bleed the brakes?
Bad Master CYL ?
No vacuum booster.

 

[CheemsK1500]

Check your rear drum cylinders for leakage, also look at your various rubber and metal lines for leaks. If there are no leaks present, it's likely a master cylinder issue. The proportion valve could also be a factor, since it can restrict flow during the bleeding process but I really encounter this problem.

It is also a good idea to bench bleed a master cylinder prior to installation to ensure that there is no trapped air.

 

[Ken B]

I did bench bleeding.
I tried to reinstall old master. Got a new one arriving tomorrow. No visible leaks all new lines. Prop valve may be adding to the issue.
Thanks.

 

[SirRobyn0]

I mean you no offence by this, but if the vehicle has sat for a bit and gotten moist in the interior the linkage can get rusty and stiff.

 

[Ken B]

good point , no offense. I will listen to all ideas.
i will be very well acquainted with all brake parts by the time I get this done. Just pulled the radiator, shroud and fan to check prop valve. the plastic "switch" in the prop valve doesnt want to come out I am skeered I am gonna snap it off. i used a small screwdriver to check the shuttle vavle. I can push it in and it bounces back. no pressure on the lines (unhooked all those again too). Heading out for more brake fluid .....only thing that aint new is prop valve and master cyl. and master gets delivered tomorrow

 

[fast 99]

Down stream fluid restrictions shouldn't cause a slow return. If there is a restriction in the system somewhere the internal master seals will slide by fluid in the cylinder and return. Those seals are designed to work in one direction only. Springs inside the master will return the pedal. Also if there is a restriction it is more likely that the brakes would drag or overheat. Just a few #'s is enough to apply disc pads.

It's likely a bad master or pedal shaft. My guess is a bad master.

 

[Ken B]

thanks. anziously awaiting the UPS man tomorrow. will throw in a new master and bleed and pray that fixes it...

 

[scrap--metal]

@Ken B Did your new master cylinder fix your brake issue?