Just for a break down I have replaced brake booster, master cylinder, rear drums shoes and hardware, and front calipers. The issue I'm having is my front driver caliper keeps locking up after I use the brakes for about 10 minutes. Any ideas on what could be causing it

 

Did you change the hoses?

 

Yes sorry I also replaced the rubber lines going from calipers to metal line

 

What do you have to do to release the pressure?
Do you have to open the bleeder to release fluid pressure?
Or can you simply force the caliper/piston open and unstick the caliper?
Is this a new to you vehicle?
When did this problem start happening? Was it after an incident?

 

I can release the pressure by the bleeder valve on the stuck caliper. I had a break issue where I was getting no brake power so I replaced the booster and master cylinder. Still had no brakes under up being a clogged brake booster check valve. I replaced that and my brakes worked like they should but after a little bit of driving and brake use the caliper locks up. Thia car is new to me

 

Problem started happening after brake booster and master cylinder was replaced and brakes started working properly

 

Recheck your prake pedal to booster and booster to MC pushrod length.
If the rods are too long they may not be fully releasing the caliper.

Primary circuit is Driver Front/Passenger Rear, its a diagonally split system.
So teh primary circuit is probably partially activated.
Do you have the specs for MC and pedal pushrod play?

 

No I do not I tried to line the push rod back up where it was at with the old booster.

 

Pushrods need to be verified for correct adjustment before installing the MC and again with a new booster verify the pedal rod is also the correct length/play.
Any preload on either pushrod will cause premature activation and dragging/lockup.

There should be 0-.4mm clearance between the bottom of the MC and the booster pushrod.
You can purchase a tool(07jag-sd40100) that can do the measurement of both booster pushrod and MC depth, might be easier if you are not sure on how to measure either with measuring calipers.
Have the engine running with a minimum of 20inHg vacuum on the booster to verify pushrod length.
To adjust this, you will need to loosen the locknut on the pushrod to booster, and adjust the nut on the booster side.

Verify the pedal is at the correct return height.
Under the dash on the driver side of the pedal, look for the brake switch and lock nut.
Loosen the locknut and back the brake light switch out and away from the pedal so it is no longer contacting the pedal.
Disconnect the electrical connection so the brake lights don't come on and drain the battery.

Pull the carpet back, there is a cutout for this so you can measure to the floorboard.
LHD
M/T: 192mm
A/T: 193mm
RHD
M/T: 167mm
A/T: 168mm

To adjust, loosen the lock nut against the clevis mounted to the pedal.
Rotate pushrod til the pedal is at the correct height.
Tighten locknut, hand tight is fine.

Screw the brake light switch back in until its plunger is fully depressed, threaded end touching the rubber pad on the brake pedal. BTW if this is missing you will need to replace it.
Back the switch out 1/4 turn, and tighten the brake light switch locknut.

Verify free plat at the brake pedal(engine off).
There should be 1-5mm of play.
If none or not enough, back the brake light switch out until there is enough.

 

I have noticed the caliper is free and released at first then apply brakes and it gradually grabs more and more and doesn't release back to normal state and begins locking up as brakes are used

 

Everything measured fine returned the caliper that was sticking for a new one and drove it about 15 miles and didn't lock up but there is definitely some sort of drag because the caliper is untouchable from heat

 

That is a sign that the rubber line going to the caliper is faulty. A piece of material is clogging the way it can be pushed with hydraulic force the one way...but wont go back the other much. Replace rubber line, and/or clear line obstruction.

 

Rubber line has already been replaced

 

Does it flow both ways? Disconnect it at the top and bottom, and verify that air will flow easily both ways.

If you compress/depress the caliper piston with a pair of grips did it feel smooth or crunchy ?

Thinking its an obstruction in the line. Debris or a classic flapper. Flash material on the inside of new part.

 

Take caliper off and inspect the knuckle, dust shield, and pads.
Verify the caliper is not cocked or the pads are not initially dragging.

Try disconnecting and plugging the vacuum to the booster, bleed it down. And go for another drive without the boost assist. Leave plenty of room to brake.

How much freeplay did you have on the MC and at the pedal?

 

This is not MC, MC not side related. Not ABS. Not caliper if it slides in and out normals for 15 miles.

Front drivers caliper rubber line has flapper. A clog in the rubber line part is not passing the brake fluid. However the heated rubber gives on the application of hydraluic force and expands to allow fluid around the obstruction.

 

I took the caliper back to the store and got a new one and it didn't completely lock up after driving but it was definitely starting to. It's like everytime I apply brakes that caliper doesn't release more and more as I drive. And the caliper was very hot to the touch which shows brake pad dragging. All other brakes work fine on the car without issue even when the other one is locking up the pedal does not change or get hard and the other brakes stop the car just fine.

 

Search flapper in brake hose and you will find tons of posts like this."I had a flapper issue with a brake hose on My 78 MG-B Roadster, rebuilt calipers, new pads and it still pulled right. Replaced both front brake hoses and problem solved."

WATCH

NO, I said it was not the caliper. This is common when the complaint is brand new AFTER a repair covering those items. The hose part might have been returned after having the caustic brake fluid put through it. Then it deteriorates on the inside, sitting on the shelf until the next customer. A flapper has flaked on the inside. Common story.

Honda/Acura Precision Team Tech. throwing you a bone. Take it.

 

Rainy day today will check tomorrow also any ideas on why it would idle up and down after it warms up

 

If the hoses are fine, its probably not the caliper after the third one, I still suspect the MC is dragging.
If the caliper is still clamping down, loosen the two nuts for the MC to booster.
If the caliper releases, you don't have enough pushrod clearance.

 

I'm gonna start popping lines up the brake system until it doesn't release

 

Check your FITV, if the nut inside loosens up the FITV will not close the cold idle passage and float causing RPM fluctuations.
Check the FAQ at the top of the forum on HOW TO: for cleaning and adjustment.

 

Idle up and down after warm? How much? At warm temp the rad fans kick on and causes RPM flux. Is this something more?

Do not pop them all just for fun...Attend to the affected side, the drivers front rubber line. Flappers dont happen in hard lines, but obstructions do. You already know the hard line flows.

 

Goes from about 1k to 2k up and down

 

If I'm sitting idle in neutral or in gear it idles up and down but not to the point of dying but annoying and noticeable