Need Help Diagnosing a Brake Issue (1 Viewer)

Joined
Nov 26, 2017
Messages
149
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Macclenny, FL USA
Hey everyone. I need some help from the good folks on MUD. Sorry if this a little long. I want to provide as much info as I can.

Some context: My right brakes seized up on me last Friday evening and the rotor was nearly molten by the time I could get safely pulled over. I had come to a stop at a stop sign and then turned out into traffic on a small highway. I immediately noticed the resistance. I pulled over as soon as I could in a church parking lot and my front right rotor was smoking. I was within reach of the Lord's water hose, so I cooled it down and got a steam face treatment (that part was nice). After a few minutes, I started the Cruiser up, tested the brakes gingerly in the parking lot a few minutes and then limped 3 miles home slowly. The caliper on the right seemed fine all the way home.

I inspected the next day and ordered new calipers and pads from Napa. I installed those yesterday and tested out the brakes on my road and then drove to Walmart to get some degreaser. When I exited the Interstate I could feel resistance and by the time I pulled into the Wal-mart parking lot, I could not budge without red-lining the tach. I went in and got my degreaser and let it cool off. I came back out, loosened the banjo bolt on the right caliper to let off the pressure, and then I drove home about 1 mile without any brake issues.

I am looking for suggestions on what I should look for. I have brand new calipers and pads. Right Caliper was the culprit again this time. What is causing the brakes on the right to not release when I let my foot off the pedal. Looking at the fluid last night, I feel the need to change it. It's getting dark. It's dark at the calipers but light in color in the reservoir.

As always, thanks in advance for your help! If there is another thread on here that sounds like this point me at it, because I missed it.

IMG_5257.jpg
 
Joined
Sep 15, 2016
Messages
697
Location
Chattanooga, TN
Are the soft lines/hoses old? I've seen these collapse and cause a single wheel to not release pressure and lock up like this. This is my top vote since it happened with two different calipers and seems to be related to retained pressure.

Are your wheel bearings tight? While not directly in line with the symptoms if the wheel bearings or caliper bolts are loose that could cause dragging in some scenarios. Always worth a check if you don't know that your wheel bearings are tight without slack in any case.

Are the pins that hold the brake pads in new or old? These can be crusty and cause the pads to get stuck in place. Releasing hydraulic pressure wouldn't be helpful in this case so this is less likely given your description. You can wire brush, sand and then grease the pins so that there is no chance of the pads sticking if it seems like it may be helpful.

Have you messed with the master cylinder lately? If the plunger rod is a bit long it can cause the master to not fully retract and thus retain brake pressure. Like dirty pins above this doesn't match your description that well because this would cause more than one side to lock up typically but if you've had the MC changed and/or adjusted the plunger this could be related.

Another cause of this would be corrosion causing the pistons to not retract in the calipers but since this has happened with two sets of calipers and since relieving pressure helps this also doesn't seem likely but I wanted to mention it just in case.
 
Joined
Nov 26, 2017
Messages
149
Location
Macclenny, FL USA
Are the soft lines/hoses old? I've seen these collapse and cause a single wheel to not release pressure and lock up like this. This is my top vote since it happened with two different calipers and seems to be related to retained pressure.

Are your wheel bearings tight? While not directly in line with the symptoms if the wheel bearings or caliper bolts are loose that could cause dragging in some scenarios. Always worth a check if you don't know that your wheel bearings are tight without slack in any case.

Are the pins that hold the brake pads in new or old? These can be crusty and cause the pads to get stuck in place. Releasing hydraulic pressure wouldn't be helpful in this case so this is less likely given your description. You can wire brush, sand and then grease the pins so that there is no chance of the pads sticking if it seems like it may be helpful.

Have you messed with the master cylinder lately? If the plunger rod is a bit long it can cause the master to not fully retract and thus retain brake pressure. Like dirty pins above this doesn't match your description that well because this would cause more than one side to lock up typically but if you've had the MC changed and/or adjusted the plunger this could be related.

Another cause of this would be corrosion causing the pistons to not retract in the calipers but since this has happened with two sets of calipers and since relieving pressure helps this also doesn't seem likely but I wanted to mention it just in case.
Thank you very much. I do not know how old the brake lines are, so they could potentially by 26 years old. Time to change them.
 
Joined
Nov 26, 2017
Messages
149
Location
Macclenny, FL USA
Still not fixed. Looking for more advice.

Sorry this is long, but I wanted to tell the entire story (again) to provide as much context as I could in case I left something out the first time.

Been having some issues with my brakes. My front right caliper seized up. I replaced it because it looked like it had 413,000 miles on it (which it did). I also changed my front pads while I was at it. Took it for a test drive and it started dragging. I pulled into a parking lot and then it would not budge without reving the engine to 2000+ RPMs. I grabbed a wrench and loosened the banjo bolt to release the pressure. The caliper released and I drove it home.

Next, I replaced the hoses on the right side. (I have hoses for the rest of the locations, but have not gotten to changing them yet.) I drove the vehicle about 200 miles over a week since changing the hoses and thought all was well.

Today I got in to run to the hardware store and felt significant drag. It wasn't far, so I pressed on got the stuff I needed an came home. The drag was there on the way home. I checked everything and decided to take it for another ride to determine full symptoms. 1st couple of miles, no issues. Then the drag started again. I could not get the vehicle above 60 at 3200+ RPM. Also, the engine temp got up to about 225 (I normally run about 186-195.) I pulled over popped the hood and checked all my vacuum lines and looked for anything that might stand out. Nothing. After 10 minutes. I closed the hood and cranked the engine. I drove back towards home about 15 miles at 60 mph with no drag and the temp stayed at 185-190 the whole way. I made a stop 3 miles from my house, shut off the engine for 10 minutes, cranked back up and immediately had the drag again as I backed out of the driveway where I was stopped. The engine temp climbed to 220 and I pulled over and popped the hood. I crawled under and looked at the brakes, and wheels. I could not see anything wrong. However, the hubs and rims were almost skin-burning hot. I could not hold my hand on them. I stayed there about 1 minutes and then drove the 1.5 miles home and the drag was with me the whole way home.

When I got home, my hubs and rims were still extremely hot. My engine temp was about 205 (I stayed at now speeds on the way home, but 205 is still hot for my Cruiser. also, let me add that when I feel this drag, the vehicle will not roll at all in drive without pressing the gas. I let everything could down and loosened the banjo bolt on the front right caliper again to let off the pressure. With the banjo bolt loosed, I pumped the brakes several times with my right hand and watched underneath the vehicle as fluid freely came out with each pump (into a bucket).

I tightened up the banjo bolt and took it for a test drive. I drove 3 miles down the road without any issue---No drag and engine temps were between 186-192. I pulled into a parking spot and shut the engine off. I sat there 10 minutes browsing mud. I cranked back up and drove home---No drag and engine temps were between 186-192.

Another detail: The pedal is high and I barely have to touch the pedal to get a response.

And one more detail: I did a rebuild on my front axle---birfs, seals, bearings, etc. About 2 months ago. since then I have driven the vehicle about 1000 miles and loved every second of it until this issue started.
This is baffling me. Probably because I do not know enough about brakes. Or I am keyed in on brakes and the brakes are not the problem at all. I am looking for any suggestions at this point. what should I do next? Is it time to replace all the brake components?

Thanks in advance for your help.

Nathan
 
Joined
Sep 15, 2016
Messages
697
Location
Chattanooga, TN
the hubs and rims were almost skin-burning hot

Does that mean that more than just the front right wheel was hot? This is a very important clue and different from what I recall earlier in this thread.

Either way I think it's very possible that the master cylinder plunger rod is adjusted a bit too long on your 80. This is really easy to confirm if/when the dragging scenario happens again and you need to check this. I think I mentioned this before but here it is again in case I didn't.

If/when you get back into the dragging/hot brakes scenario loosen the 4 nuts that hold the master cylinder to the brake booster. Don't remove these nuts just loosen them until there is a visual gap between the MC and booster. You can unthread the nuts to the end of the studs they are on and then pull the MC away from the booster to help create that gap. Then, with the gap in place and the nuts backed out to the stud-ends drive a short/slow distance to test and see if the problem is resolved. Your brakes will still work but don't drive more than necessary with the nuts loose. If the plunger is too long your binding will be resolved immediately and then you'll know you just need to adjust/shorten the plunger rod.

If this is the problem shortening the plunger rod is really easy. A pair of pliers to hold the rod and 8mm (or close to that size) combination wrench will do the trick. You don't have to disconnect any lines on the MC just remove the 4 nuts and then pull the MC away from the booster until the MC is past the end of the 4 studs. Then use a short rod or something similar to press and hold the brake pedal down so that the end of the rod is accessible in the gap between the MC and the booster. Then, hold the rod from turning with the pliers and turn the threaded end in a bit and try again. Since it's pretty easy to get to this adjustment start small and test a few times. When there is a slight gap between rod end and the MC plunger your pedal should feel less tight and your brakes take a bit longer to engage. There is also a tool that will help you get this to factory spec but you can at least resolve the problem by shortening the rod til the pedal feels a bit looser to stop the brake binding. I doubt you'll need more than a turn of adjustment but that's just a guess.

The fact that your brake pedal is so tight is a big clue here. Also, it's possible to get the rod adjusted so close to the limit that there is no problem when things are cool but where the brakes will start to drag when it gets hot under the hood (yep, I've adjusted it too tight and discovered this on a hot day) so leave a bit of room for thermal expansion.

Hope that helps.
 
Joined
Nov 26, 2017
Messages
149
Location
Macclenny, FL USA
Does that mean that more than just the front right wheel was hot? This is a very important clue and different from what I recall earlier in this thread.

Either way I think it's very possible that the master cylinder plunger rod is adjusted a bit too long on your 80. This is really easy to confirm if/when the dragging scenario happens again and you need to check this. I think I mentioned this before but here it is again in case I didn't.

If/when you get back into the dragging/hot brakes scenario loosen the 4 nuts that hold the master cylinder to the brake booster. Don't remove these nuts just loosen them until there is a visual gap between the MC and booster. You can unthread the nuts to the end of the studs they are on and then pull the MC away from the booster to help create that gap. Then, with the gap in place and the nuts backed out to the stud-ends drive a short/slow distance to test and see if the problem is resolved. Your brakes will still work but don't drive more than necessary with the nuts loose. If the plunger is too long your binding will be resolved immediately and then you'll know you just need to adjust/shorten the plunger rod.

If this is the problem shortening the plunger rod is really easy. A pair of pliers to hold the rod and 8mm (or close to that size) combination wrench will do the trick. You don't have to disconnect any lines on the MC just remove the 4 nuts and then pull the MC away from the booster until the MC is past the end of the 4 studs. Then use a short rod or something similar to press and hold the brake pedal down so that the end of the rod is accessible in the gap between the MC and the booster. Then, hold the rod from turning with the pliers and turn the threaded end in a bit and try again. Since it's pretty easy to get to this adjustment start small and test a few times. When there is a slight gap between rod end and the MC plunger your pedal should feel less tight and your brakes take a bit longer to engage. There is also a tool that will help you get this to factory spec but you can at least resolve the problem by shortening the rod til the pedal feels a bit looser to stop the brake binding. I doubt you'll need more than a turn of adjustment but that's just a guess.

The fact that your brake pedal is so tight is a big clue here. Also, it's possible to get the rod adjusted so close to the limit that there is no problem when things are cool but where the brakes will start to drag when it gets hot under the hood (yep, I've adjusted it too tight and discovered this on a hot day) so leave a bit of room for thermal expansion.

Hope that helps.

It does help. I will do this tomorrow.

Would the master cylinder issue affect my engine temp? And if so, why? Thanks!

And on the hubs and rims, both sides were hot.

Thanks again.
 
Joined
Sep 15, 2016
Messages
697
Location
Chattanooga, TN
Would the master cylinder issue affect my engine temp? And if so, why? Thanks!

This is probably a yes and simply because you are pushing the engine hard to overcome a lot of resistance. I qualify it with "probably" because there are possibly other factors at play etc. but that seems academic. If your brakes are dragging and you are heavy footing the throttle to maintain speed then the engine is going to run hotter.

However, if your cooling system was at full capacity it should be pretty hard to get to the temps you mentioned. Your Tstat would be wide opening, circulating coolant through a clean/clear radiator (inside and out) and your fan clutch would be driving the fan really hard pulling lots of air. Depending on how fast you were travelling, engine rpms, ambient temps etc. etc. I'm sure it would be possible to run that hot with dragging brakes and a heavy foot but it's also possible that your cooling system needs a bit of attention as well. I'm of the opinion that fan clutch tuning is a good place to start if all else looks good and is in decent shape. Of course this is a rabbit trail, back to brakes! Check your master cylinder plunger rod length and let us know what you find.
 
Joined
Nov 26, 2017
Messages
149
Location
Macclenny, FL USA
This is probably a yes and simply because you are pushing the engine hard to overcome a lot of resistance. I qualify it with "probably" because there are possibly other factors at play etc. but that seems academic. If your brakes are dragging and you are heavy footing the throttle to maintain speed then the engine is going to run hotter.

However, if your cooling system was at full capacity it should be pretty hard to get to the temps you mentioned. Your Tstat would be wide opening, circulating coolant through a clean/clear radiator (inside and out) and your fan clutch would be driving the fan really hard pulling lots of air. Depending on how fast you were travelling, engine rpms, ambient temps etc. etc. I'm sure it would be possible to run that hot with dragging brakes and a heavy foot but it's also possible that your cooling system needs a bit of attention as well. I'm of the opinion that fan clutch tuning is a good place to start if all else looks good and is in decent shape. Of course this is a rabbit trail, back to brakes! Check your master cylinder plunger rod length and let us know what you find.
Thanks again. Will do. I appreciate your help.
 
Joined
Nov 26, 2017
Messages
149
Location
Macclenny, FL USA
Thanks again. Will do. I appreciate your help.
Hey. Well, I went for a short drive and 2 miles into it I started experiencing the drag. Pulled into a parking lot and I loosen the four bolts that hold the master cylinder in. I pulled it out to create the gap I even wedged a 10 mm wrench between the gap to keep it open. Immediately I got some of my pedal back, but the drag is still there. Any suggestions?
 
Joined
Dec 24, 2018
Messages
79
Location
Denver, Co
Stopping these fun beasts is as much fun as driving them.
The engineering and dynamics of the brake system are at its peak for this big of a rig and purpose. Hence many mudders do changes.
Our rig is still factory so factory experience and mistakes.

Your issue specifically.
Brake lines as noted for backflow. Looks like you tried.
Calipers, pads, pad pins, all good.
Brake pedal Master cylinder rod length. Yes this can be adjusted and worth checking under the dash. Would not do the specific right side.

My mistakes and areas of not thinking outside or inside the correct box.
Caliper and Pads. The proper grease should be included with pads to install at contact point of pad shim and caliper piston/clamp.
The Pad pins should have different grease for the pads to extend and retract. Sil GLyde is what I use.

Master cylinder brake rod.
Many a Master cylinder have been replaced or rebuilt.
The Idea as noted of "Loosening 4 bolts on master cylinder" to increase rod length. This is concerning and not right.
Check FSM for Rod adjustment under the left dash under steering column
This lead me to possible contributor to problem

Brake Booster
If still Original or even 2nd. Replace the brake booster. Ours was bad for a long time without realizing it was the problem.
On the booster. Make sure that the valve off of the manifold and the line is providing pressure.
This is also a good time to adjust Brake rod.

Master Brake Cylinder.
this could be the culprit for the right front wheel lock up. I still doubt it though.
If replacing Booster and Master Cylinder is old, light comes on, float does not work, leaks etc replace or rebuild.

Brake fluid.
Remove existing fluid in master cylinder if reusing.
Have some one help you. For me it's my daughter.
Pour new brake fluid in reservoir. Start truck and pump lines till RR is clear. Old fashioned, open,/close/open/close as your assistant works the brake pedal.
The RR is farthest and takes longest. May even need to stop half way and check to fill reservoir again .
Commence to LR,RF and Finally LF to bleed the brake system.
Oh yeah, use proper 10mm flared brake wrench and put the rubber booties back on.

This is the most interesting for me. Have found that cleaning and clean fluids makes these trucks hum.
It is also very important use the right grease on the right part or no grease at all.

I have more time than money so work funny.
Brake fluid cheap, time with daughter. First thing to do. Bleed the whole system with new brake fluid.
Test drive, may fix the problem, if not

Install new brake booster. Think about master cylinder but would not until trying new booster.
The reservoir should not of leaked so no need to rebleed, hopefully. The FSM describes the pedal resistance. Generally a slight gap then hard pedal with a slight pressure.
Test drive with new Brake booster

Side note
The description of what happened to the RF Rotors is a good indicator that new ones are also needed. When they get hot they warp.
Good luck
 
Joined
Nov 26, 2017
Messages
149
Location
Macclenny, FL USA
Stopping these fun beasts is as much fun as driving them.
The engineering and dynamics of the brake system are at its peak for this big of a rig and purpose. Hence many mudders do changes.
Our rig is still factory so factory experience and mistakes.

Your issue specifically.
Brake lines as noted for backflow. Looks like you tried.
Calipers, pads, pad pins, all good.
Brake pedal Master cylinder rod length. Yes this can be adjusted and worth checking under the dash. Would not do the specific right side.

My mistakes and areas of not thinking outside or inside the correct box.
Caliper and Pads. The proper grease should be included with pads to install at contact point of pad shim and caliper piston/clamp.
The Pad pins should have different grease for the pads to extend and retract. Sil GLyde is what I use.

Master cylinder brake rod.
Many a Master cylinder have been replaced or rebuilt.
The Idea as noted of "Loosening 4 bolts on master cylinder" to increase rod length. This is concerning and not right.
Check FSM for Rod adjustment under the left dash under steering column
This lead me to possible contributor to problem

Brake Booster
If still Original or even 2nd. Replace the brake booster. Ours was bad for a long time without realizing it was the problem.
On the booster. Make sure that the valve off of the manifold and the line is providing pressure.
This is also a good time to adjust Brake rod.

Master Brake Cylinder.
this could be the culprit for the right front wheel lock up. I still doubt it though.
If replacing Booster and Master Cylinder is old, light comes on, float does not work, leaks etc replace or rebuild.

Brake fluid.
Remove existing fluid in master cylinder if reusing.
Have some one help you. For me it's my daughter.
Pour new brake fluid in reservoir. Start truck and pump lines till RR is clear. Old fashioned, open,/close/open/close as your assistant works the brake pedal.
The RR is farthest and takes longest. May even need to stop half way and check to fill reservoir again .
Commence to LR,RF and Finally LF to bleed the brake system.
Oh yeah, use proper 10mm flared brake wrench and put the rubber booties back on.

This is the most interesting for me. Have found that cleaning and clean fluids makes these trucks hum.
It is also very important use the right grease on the right part or no grease at all.

I have more time than money so work funny.
Brake fluid cheap, time with daughter. First thing to do. Bleed the whole system with new brake fluid.
Test drive, may fix the problem, if not

Install new brake booster. Think about master cylinder but would not until trying new booster.
The reservoir should not of leaked so no need to rebleed, hopefully. The FSM describes the pedal resistance. Generally a slight gap then hard pedal with a slight pressure.
Test drive with new Brake booster

Side note
The description of what happened to the RF Rotors is a good indicator that new ones are also needed. When they get hot they warp.
Good luck
Thanks!
 
Joined
Sep 15, 2016
Messages
697
Location
Chattanooga, TN
went for a short drive and 2 miles into it I started experiencing the drag. Pulled into a parking lot and I loosen the four bolts that hold the master cylinder in. I pulled it out to create the gap I even wedged a 10 mm wrench between the gap to keep it open. Immediately I got some of my pedal back, but the drag is still there.

What did your pedal feel like after this? With the gap between MC and booster could you detect a bit of free-play in the pedal before your brakes engaged? A wrench-thickness-worth is a lot of gap and should have been enough to fully release rod from the MC plunger allow it the MC to fully retract. If you could indeed feel free play in the pedal before any braking action then I think you can rule out my theory of the rod being adjusted too long and holding the plunger in a bit.

The Idea as noted of "Loosening 4 bolts on master cylinder" to increase rod length. This is concerning and not right.
Check FSM for Rod adjustment under the left dash under steering column

I agree that loosening the 4 bolts and creating a gap is non-conventional but it is a quick/easy way to figure out if the MC plunger is being depressed after the brake pedal is fully released. I've had success using this method on an 80 series land cruiser so know it can be effective in this scenario with a tight brake pedal and major hydraulic brake drag on multiple wheels. Read above to see that Nathan has confirmed that it's no longer just the front right that's dragging which is very relevant. The adjustment under the hood, behind the the MC is a valid procedure as you can see from the FSM pic below. This is separate from the rod adjustment under the dash which is more related to pedal free play from the booster.

1996 80 series FSM brake rod adjust.png


Nathan, if you are are confident that you indeed created free play and that the rod was not engaged in holding the MC plunger down then there aren't a lot of other likely sources for retained hydraulic pressure to my knowledge. I'll mention that it's feasible that the ABS could be causing some issue here but I've never heard of that happening and I think you'd have other clues pointing to it if it was the issue. Maybe someone else can chime in on that possibility.

My next guess, based on my own experiences, would be the MC. That's not to say that I'd change the MC next but I'd have it in my mind as I tested and reviewed the system and tried to rule out all easy options before diving into an MC change and full bleed. Of course, you still need to change more hoses so you could knock it all out at once and in your shoes I would change the MC whenever you change the hoses if this issue is still present just to help rule it out.

I have seen an MC fail internally such that it braked fine but would sometime retain fluid and other times not. This was 15 or so years ago so I don't recall exactly what was wrong with it but as I recall there was a loose part internally that was preventing full retraction or was blocking the fluid release path sometimes and not others. This was a rebuilt mc that I installed and drove for 3 or 4 months before I figured out the problem. I worked through every other part of the system before finally trying another MC because I considering the MC to be new and not the issue. I don't recall what your history is with this MC but based on my previous experience this is something I'd be keeping an eye on as a possibility.

A great option for a new MC is: ADVICS BMT-046

It's a quality part, comes with the fluid reservoir and cap.

Good luck figuring this out!
 
Joined
Dec 24, 2018
Messages
79
Location
Denver, Co
What did your pedal feel like after this? With the gap between MC and booster could you detect a bit of free-play in the pedal before your brakes engaged? A wrench-thickness-worth is a lot of gap and should have been enough to fully release rod from the MC plunger allow it the MC to fully retract. If you could indeed feel free play in the pedal before any braking action then I think you can rule out my theory of the rod being adjusted too long and holding the plunger in a bit.



I agree that loosening the 4 bolts and creating a gap is non-conventional but it is a quick/easy way to figure out if the MC plunger is being depressed after the brake pedal is fully released. I've had success using this method on an 80 series land cruiser so know it can be effective in this scenario with a tight brake pedal and major hydraulic brake drag on multiple wheels. Read above to see that Nathan has confirmed that it's no longer just the front right that's dragging which is very relevant. The adjustment under the hood, behind the the MC is a valid procedure as you can see from the FSM pic below. This is separate from the rod adjustment under the dash which is more related to pedal free play from the booster.

View attachment 2517708

Nathan, if you are are confident that you indeed created free play and that the rod was not engaged in holding the MC plunger down then there aren't a lot of other likely sources for retained hydraulic pressure to my knowledge. I'll mention that it's feasible that the ABS could be causing some issue here but I've never heard of that happening and I think you'd have other clues pointing to it if it was the issue. Maybe someone else can chime in on that possibility.

My next guess, based on my own experiences, would be the MC. That's not to say that I'd change the MC next but I'd have it in my mind as I tested and reviewed the system and tried to rule out all easy options before diving into an MC change and full bleed. Of course, you still need to change more hoses so you could knock it all out at once and in your shoes I would change the MC whenever you change the hoses if this issue is still present just to help rule it out.

I have seen an MC fail internally such that it braked fine but would sometime retain fluid and other times not. This was 15 or so years ago so I don't recall exactly what was wrong with it but as I recall there was a loose part internally that was preventing full retraction or was blocking the fluid release path sometimes and not others. This was a rebuilt mc that I installed and drove for 3 or 4 months before I figured out the problem. I worked through every other part of the system before finally trying another MC because I considering the MC to be new and not the issue. I don't recall what your history is with this MC but based on my previous experience this is something I'd be keeping an eye on as a possibility.

A great option for a new MC is: ADVICS BMT-046

It's a quality part, comes with the fluid reservoir and cap.

Good luck figuring this out!
Great points!! IT is still the RF WHEEL? Correct
Got to ask were the brake lines you replaced "FLAKING" on the inside?
Where the brakes lines internally cracked or cracking?

As jpoole noted much else to the hydraulics.
This makes wonder if some of the internal brake line parts is some where between Master Brake Cylinder and bleeder valve/ Caliper.
Thanks for also noting the adjustment rod Brake rod at booster/master cylinder plus FSM steps!!!
Took me awhile so be safe.
 
Joined
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Messages
697
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Chattanooga, TN
@yknot123

Note this from Nathan above:

However, the hubs and rims were almost skin-burning hot. I could not hold my hand on them.

Lots of plural references and I think he confirmed elsewhere that it's no longer just the right front though I didn't look beyond the above quote.

I believe that he's only changed the hose on the front right caliper and that he changed the caliper at the same time on that wheel.

I also believe that to get the brakes to stop binding that he's opened the banjo fitting on the brake hose connecting to the front right caliper every time. That means that the brakes are dragging because of retained hydraulic pressure. The fact that the pressure is retained on more than one wheel and that one of the front wheels has a new hose pretty much removes collapsed brake hoses as the cause. It also removes binding pads in the calipers, rusty caliper pistons, rusty slide pins, loose bearings and other mechanical causes.

At this point, per the information Nathan has shared, the system is retaining pressure after the brake pedal is physically released. In my opinion this points to the MC either being slightly held in a depressed mode so that the plunger can't release or MC internal issues/failure being the most likely causes. Of course, with online/remote diagnosis it's often possible to be missing important information and therefore giving bad recommendations...
 
Joined
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Messages
149
Location
Macclenny, FL USA
@yknot123

Note this from Nathan above:



Lots of plural references and I think he confirmed elsewhere that it's no longer just the right front though I didn't look beyond the above quote.

I believe that he's only changed the hose on the front right caliper and that he changed the caliper at the same time on that wheel.

I also believe that to get the brakes to stop binding that he's opened the banjo fitting on the brake hose connecting to the front right caliper every time. That means that the brakes are dragging because of retained hydraulic pressure. The fact that the pressure is retained on more than one wheel and that one of the front wheels has a new hose pretty much removes collapsed brake hoses as the cause. It also removes binding pads in the calipers, rusty caliper pistons, rusty slide pins, loose bearings and other mechanical causes.

At this point, per the information Nathan has shared, the system is retaining pressure after the brake pedal is physically released. In my opinion this points to the MC either being slightly held in a depressed mode so that the plunger can't release or MC internal issues/failure being the most likely causes. Of course, with online/remote diagnosis it's often possible to be missing important information and therefore giving bad recommendations...


Thank you all for taking the time to respond to me. Please see my answers to your questions below.

@jpoole What did your pedal feel like after this? With the gap between MC and booster could you detect a bit of free-play in the pedal before your brakes engaged? It was not as hard and yes I got free play back in the pedal.

@yknot123 IT is still the RF WHEEL? Correct That's where I feel it most and where I keep going to release the pressure and get the drag to go away, but maybe I have been to keyed in on the RF and I should try releasing the pressure on one of the other calipers next time. I have just been loosening the banjo bolt enough to release some fluid and allow the brakes to relax.
Got to ask were the brake lines you replaced "FLAKING" on the inside? No I did not see that and I cut one in half to inspect it fully.
Where the brakes lines internally cracked or cracking? No.

This may just be a coincidence and an indication of my current luck, but I have a new wrinkle to add since my last post to this thread: As soon as I released the pressure the last time I was experiencing the drag, I started having a rough idle. The Scan Gauge showed error code P0301--Cylinder One Misfire. I read on Mud before that can sometimes be caused by a vacuum leak. The worst looking hose under my hood is the vacuum line that goes to the brake booster (already ordered a replacement). Any chance the rough idle could be related to my brake woes?
As info, the distributor cap, spark plugs and wires are all about 1 year old. I have not been able to pull the plug for cylinder one to check it yet.

Thanks again!
 
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Thank you all for taking the time to respond to me. Please see my answers to your questions below.

@jpoole What did your pedal feel like after this? With the gap between MC and booster could you detect a bit of free-play in the pedal before your brakes engaged? It was not as hard and yes I got free play back in the pedal.

@yknot123 IT is still the RF WHEEL? Correct That's where I feel it most and where I keep going to release the pressure and get the drag to go away, but maybe I have been to keyed in on the RF and I should try releasing the pressure on one of the other calipers next time. I have just been loosening the banjo bolt enough to release some fluid and allow the brakes to relax.
Got to ask were the brake lines you replaced "FLAKING" on the inside? No I did not see that and I cut one in half to inspect it fully.
Where the brakes lines internally cracked or cracking? No.

This may just be a coincidence and an indication of my current luck, but I have a new wrinkle to add since my last post to this thread: As soon as I released the pressure the last time I was experiencing the drag, I started having a rough idle. The Scan Gauge showed error code P0301--Cylinder One Misfire. I read on Mud before that can sometimes be caused by a vacuum leak. The worst looking hose under my hood is the vacuum line that goes to the brake booster (already ordered a replacement). Any chance the rough idle could be related to my brake woes?
As info, the distributor cap, spark plugs and wires are all about 1 year old. I have not been able to pull the plug for cylinder one to check it yet.

Thanks again!
@yknot123

Note this from Nathan above:



Lots of plural references and I think he confirmed elsewhere that it's no longer just the right front though I didn't look beyond the above quote.

I believe that he's only changed the hose on the front right caliper and that he changed the caliper at the same time on that wheel.

I also believe that to get the brakes to stop binding that he's opened the banjo fitting on the brake hose connecting to the front right caliper every time. That means that the brakes are dragging because of retained hydraulic pressure. The fact that the pressure is retained on more than one wheel and that one of the front wheels has a new hose pretty much removes collapsed brake hoses as the cause. It also removes binding pads in the calipers, rusty caliper pistons, rusty slide pins, loose bearings and other mechanical causes.

At this point, per the information Nathan has shared, the system is retaining pressure after the brake pedal is physically released. In my opinion this points to the MC either being slightly held in a depressed mode so that the plunger can't release or MC internal issues/failure being the most likely causes. Of course, with online/remote diagnosis it's often possible to be missing important information and therefore giving bad recommendations...
Thank you all for taking the time to respond to me. Please see my answers to your questions below.

@jpoole What did your pedal feel like after this? With the gap between MC and booster could you detect a bit of free-play in the pedal before your brakes engaged? It was not as hard and yes I got free play back in the pedal.

@yknot123 IT is still the RF WHEEL? Correct That's where I feel it most and where I keep going to release the pressure and get the drag to go away, but maybe I have been to keyed in on the RF and I should try releasing the pressure on one of the other calipers next time. I have just been loosening the banjo bolt enough to release some fluid and allow the brakes to relax.
Got to ask were the brake lines you replaced "FLAKING" on the inside? No I did not see that and I cut one in half to inspect it fully.
Where the brakes lines internally cracked or cracking? No.

This may just be a coincidence and an indication of my current luck, but I have a new wrinkle to add since my last post to this thread: As soon as I released the pressure the last time I was experiencing the drag, I started having a rough idle. The Scan Gauge showed error code P0301--Cylinder One Misfire. I read on Mud before that can sometimes be caused by a vacuum leak. The worst looking hose under my hood is the vacuum line that goes to the brake booster (already ordered a replacement). Any chance the rough idle could be related to my brake woes?
As info, the distributor cap, spark plugs and wires are all about 1 year old. I have not been able to pull the plug for cylinder one to check it yet.

Thanks again!
Good day all.
Great follow up jpoole. Thanks for clarifying.
His new symptom and his repair of loosening the banjo nut. The code also points to the Vacuum pressure to Brake Booster. There is a fitting and valve that comes off the intake manifold, that the vacuum hoses attaches. If this is not working properly the diaphragm inside the booster will act funny. Some pressure no pressure, to much pressure etc Sound familiar. Check fitting/valve on intake to vacuum line to booster
Great input from all and would follow up with the vacuum line/valve, rod length, master cylinder, brake booster.
Much seems to be made of bleeding brakes. It really is not that much work. Once completely flushed, it is very easy to check for bubbles, soft pedal, etc
When you get good brakes it will all be worth it keep after it.
 

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