Newbie with questions

[90cnfranger]

Im new to this forum but have used a lot of useful information from all that post and respond on here. So a little background on my truck. its 1990 Ranger xlt 2.3l. This truck was given to me by my late father who got it from his dad. It hasn't been driven in a few years and recently got it up and running. I made a 100 mile trip in it and noticed the passenger side brakes seem to be sticking then began to smoke. I've replaced the calipers, brakes, inner and outer bearings along with the rotors. Test drove it few mins ago and the same side is do the exact as before. So should i replace the flex brake line to the caliper or jump into a new brake booster. Sorry about the long post, and if anyone one has suggestions feel free to chime in.

 

[RonD]

Welcome to TRS

Yes, could be flex line is broken inside and acting as a valve

Jack up that wheel and open bleeder valve to see if there is any pressure inside caliper, shouldn't be.
Now spin the wheel, should spin easily, but pads will rub slightly.
Now start the engine and pump the brakes a few times, turn off engine
Spin the wheel again, should spin same as before, if it is tight then open bleeder again and you should see pressure released.

If this happens then yes, replace flex line

When you open the bleeder valve on any wheel brake fluid will flow out, but just by Gravity since Master is higher than Bleeder, it shouldn't squirt out
And no you won't be letting air into the system by opening a bleeder if you don't touch the brake pedal while it is open

 

[90cnfranger]

When I was replacing the calipers the passenger side which is the side in question, no fluid was coming out of the flex hose. When I did the driver side once the caliper was unhooked I had a constant flow of brake fluid coming out. I've read on here of the hoses swelling on the inside and acting like a one way valve. Would like to mention that when driving the truck the brakes will drag on the passenger side then you can feel them release.

 

[RonD]

No flow would be a good sign that its time to replace it.

There is a lot of pressure pushing fluid thru the brake lines when you press down the brake pedal.
But very little pressure to push fluid back to Master
Flex hose shows no flow without pressure, gravity is not enough, and should be.
So it would pass fluid with brake pressure but not release it very fast

There are no "return springs" on disc brakes like there are on shoes/drums
Basically the pressure of the clamping force being released is all that pushes fluid back out to Master and releases pressure on the pads

 

[tomw]

The 'square cut' sealing rings on the caliper pistons are flexed when you step on the brake pedal. When you release pressure, the rings will want to return to their relaxed position, square in the caliper bore. That force along with any uneven rotor surface is all that will return the pistons and make the pads relax from the rotor. If the flexible hose is internally blocked, it can keep the pads in touch with the rotor, and either make them drag, or get the pads & rotor heated up beyond normal temperature(or both).
tom

 

[90cnfranger]

So after replacing the flex hoses and a good bleed it fixed my problem. I appreciate all that helped narrow this down.