Brake lockup?

[GLTHFJ60]

In one of your early posts you asked Johnny about a nicked line. Clearly the line you're talking about is not leaking but did it get hit in such a way it may have kinked?

To elaborate on what happened, while cutting the DS u-bolts on the rear axle, the grinder skipped and hit a brake hard line. It put a small nick in the line from the grinding wheel. The line is not visibly deformed other than the shiny spot. I would not expect this to be related, but I suppose it may.

 

[Rice]

To elaborate on what happened, while cutting the DS u-bolts on the rear axle, the grinder skipped and hit a brake hard line. It put a small nick in the line from the grinding wheel. The line is not visibly deformed other than the shiny spot. I would not expect this to be related, but I suppose it may.

I would have to agree. My wonder was whether an axle dropped on it such as to cause a collapse. Really looking forward to learning the outcome of this one.

 

[GLTHFJ60]

I would have to agree. My wonder was whether an axle dropped on it such as to cause a collapse. Really looking forward to learning the outcome of this one.

There was no other damage to the hard lines done to my knowledge during the suspension swap. I suppose it's possible that just stretching the soft brake lines has caused them to fail internally? Maybe they're swelling?

 

[Rice]

There was no other damage to the hard lines done to my knowledge during the suspension swap. I suppose it's possible that just stretching the soft brake lines has caused them to fail internally? Maybe they're swelling?

Failing soft line is my thought if the problem is in the rear. It happens on the front also but is a much smaller occurrence compared with just having a frozen caliper.

 

[ontherxs]

I'll try to get some time to reproduce it driving around the hood and I'll jack it up and inspect further. Thanks for the input. @Rice if the fluid is at a point you have fade, the e-brake would also have less tension in it, correct. Things cool down and ebrake has normal tension when engaged. Just checking my thought process. This is my first brake adventure.

 

[Rice]

There was no other damage to the hard lines done to my knowledge during the suspension swap. I suppose it's possible that just stretching the soft brake lines has caused them to fail internally? Maybe they're swelling?

Failing soft line is my thought if the problem is in the rear. It happens on the front also but is a much smaller occurrence compared with just having a frozen caliper.

I'll try to get some time to reproduce it driving around the hood and I'll jack it up and inspect further. Thanks for the input. @Rice if the fluid is at a point you have fade, the e-brake would also have less tension in it, correct. Things cool down and ebrake has normal tension when engaged. Just checking my thought process. This is my first brake adventure.

On paper the e-brake is independent from the main brake circuit, however, if the rear shoes have already been pushed up to the drum by pressure in the main circuit the work of pulling up the e-brake handle has already been done. This is a clue since the e-brake is rear wheels only. Still can't rule out a bad master cylinder but we will know more when you get a chance to reproduce the problem.

 

[ontherxs]

OK I haven't had a chance to take the wheel off yet but I am certain now it's the rear passenger side. In trying to reproduce the problem, I took some temperature reading of the discs and drums and then rode around for a bit. When I stopped the disks and the read DD drum where between 150-180F the rear PS was over 250F.

So next I'll pull of the drum and take a look and see what's sticking. I was half tempted to bring it down to the guys at the Oberlin Exxon since I really want to drive it and either way the system needs to be flushed. I cancled the appointment bxs I want to figure it out then have the work done. I've had no weekend time wrench else I'd tackle it all myself.

Thinking pad is stuck closed which causes the fluid to boil and lose pressure, soft line collapses enough with the loss of pressure to act a check valve and brake is stuck full closed. Things cool off pump the system backup and we're back to square one. Or none of that cause this IS my first brake rodeo.

 

[Rice]

OK I haven't had a chance to take the wheel off yet but I am certain now it's the rear passenger side. In trying to reproduce the problem, I took some temperature reading of the discs and drums and then rode around for a bit. When I stopped the disks and the read DD drum where between 150-180F the rear PS was over 250F.

So next I'll pull of the drum and take a look and see what's sticking. I was half tempted to bring it down to the guys at the Oberlin Exxon since I really want to drive it and either way the system needs to be flushed. I cancled the appointment bxs I want to figure it out then have the work done. I've had no weekend time wrench else I'd tackle it all myself.

Thinking pad is stuck closed which causes the fluid to boil and lose pressure, soft line collapses enough with the loss of pressure to act a check valve and brake is stuck full closed. Things cool off pump the system backup and we're back to square one. Or none of that cause this IS my first brake rodeo.

This is good info. Now it's time to determine if the lockup is happening because of a fault in the main brake circuit or in the emergency brake. If the E-brake is not completely releasing it can be the cause of the heat AND it can easily be happening on only one wheel. If it is safe for you to temporarily unhook the E-brake long enough for a test drive you should be able to determine if the issue is there.

EDIT - My money is still on the flexible hose going to that wheel being constricted due to interior degrading.

 

[dbenke]

there should only be one flex hose going to the rear IIRC

 

[Rice]

there should only be one flex hose going to the rear IIRC

Ehh, you're right. And it's really doubtful that one is locking up one wheel.

 

[ontherxs]

Some updates for us over in my main build thread. Short story, not sure exactly the issue but going to refresh the rear brake system and start over.

 

[runningdaddy]

Looking forward to hearing what you find. I've started having the same problem. My PS rear wheel was smoking one night coming home. Had the brake cylinders replaced and brake fluid system flushed. I couldn't get Firestone to swap the brake hoses though.
Things ran well until yesterday when I had the same initial problem you did. Backing into a parking spot and the cruiser felt like it was tied to a stump. No power. Brake fluid level was fine.
Frustrating!!! Hoping the MUD team can help resolve this issue.

 

[ontherxs]

@runningdaddy check out my main build thread in the signature. For me it was a collapsed line toward the front of the truck. Bunch of pics and steps in the thread. Replacing the lines was not hard. I couldn't find one long enough to run the full length of the truck so it's actually two lines coupled mid way.

 

[runningdaddy]

Thanks! I missed the link in your signature block.
On to the build thread.