Help I'm stuck I had to slam on the brakes to avoid hitting something ands now they are locked up any ideas

 

Did you extend the pistons from the calipers due to worn brakes, or maybe the guide pins are bad. You may be able to loosen the bleeder screws and get her free, but do not drive it, unless properly bled and checked out.

Calipers locking up is not uncommon. You can get everything apart and probably free it up, might just take an hour or two.

 

Thanks, Woodnthings!! My phone ran out of battery so I could not reply earlier. The drivers side rear wheel brake was stuck. I loosened the bleeder fitting and got a quick squirt and the brake released. I drove home slowly and everything seemed fine. I'll take it in tommorow to have the system bled. Is this common, or might I have something wrong with my brakes?

 

The rubber hose is shot that feeds the back axle's brakes. It causes the pressure not to bleed off. The pressure gets trapped due to the rubber brake line is collapsing. You manually releasing the pressure via the bleeder is the proof. I would put a new rear rubber brake line on your "to do" list.

 

How does excessive pressure cause hose collapse? Somehow that just doesn't seem possible.

Though I find it difficult to believe, anecdotal tales tell of a flexible brake hose failure mode that somehow becomes a one-way valve for the fluid.

I guess if this happened to me, and I got that "squirt" by opening a bleeder, I'd first think about replacing the three flex hoses on the rear. One at each wheel, and one coming down off the body to the rear-end.

I STILL don't understand this possible failure mode, but I'm not saying it couldn't happen.

Pop

 

It happened to me a couple times. Once in a 66 sunbeam. Stepped on the brakes and the pressure stayed on the calipers. Luckily at home in my driveway. Took the hoses off and the it was sealed shut right at the crimp. That was a first for me. When i took the hoses off I couldn't even blow air through with the air compressor and a blow gun. Took a lot of pressure to anything through.

And my old motorhome. Stuck along side the road in Virginia a year later. That one I used a drill bit to drill it out were it was crimped to get me going. Limped to a shop to have the hose replaced.

I think it is like all that pressure will leak through those crimp connections. But when you let off on the brake pedal, only half of the pressure will leak back. Maintaining half the pressure on the calipers.

 

Dan, I don't doubt for a minute that this HAS happened to you, and many others over the years, JUST like that. But I'm doubtful that fluids can work like that.

There's more to this. There HAS to be......

Anybody with a degree in Fluid Dynamics here?

Hello, hello, calling all Fluidicians!

Pop

 

I think it has to do with the rubber swelling(saturated) due to something. Possibly age, or the fluid. But at the ends of the hose the crimped fitting is on the outside of the hose. The hose can not swell bigger due to it being trapped. So it collapses the ID of the hose. Just at the ends. I had a picture of it but can not find it. The ID of the hose was totally blocked off at the crimps. Say it takes 1000lbs of pressure to get fluid through. But upon releasing it can't not bleed back. Trapping 1000lbs. Or 500. Similar to a Kink.

 

The ends (fittings) of a hydraulic hose have both inner and outer metal parts. The flexible "rubber" hose is crimped or "squeezed" between them. How can the inside collapse if there is an inner metal lining at the ends? You are suggesting that the inner metal part no longer is able to keep the "rubber" from collapsing?

This isn't making any sense to me.

Please look for that photo, Dan, as it might have some clues to this weirdness (at least for me it's weird...).

Pop

 

I understand your debating and it was a first for me also, Twice in fact. Both times i didn't have the elbow fittings. When i took the hoses off the sunbeam. I could not blow air through them with the blow gun. They were sealed shut. But man did they hold the pressure on the caliper. When i cracked the caliper loose i got shot with brake fluid that was when i called dad. And he said to check the hoses. When i did i discovered they were swollen shut at the fittings. I ran a .062 drill bit in the end and i got rubber out. Then i tried the blow gun again and whalla. But i didn't want to use the lines because they were faulty. So i got two new ones.

The motorhome going through virginia. I stopped a red light and when i went to go the rear brakes was locked. I got into a plaza and when i cracked the bleeder loose i got shot with break fluid again. With this vehicle, Both rear breaks operated from one rubber hose. I pulled in the back under a shade tree and when i stopped, the brakes locked again. I pulled the rubber hose off, From my experience,. The rubber hose was not allowing brake fluid pressure to bleed back through. Or me blowing on it either. So i ran a .062 drill bit through it using the battery drill to open it up, Reinstalled and Re-bleed. Brakes were working good. Then i drove to the ford dealer to have them put a new line on.

I can't explain it from the picture you posted. But i think it was at the very edge were i drew the red line or on fittings that the center portion isn't flush with the edge and possible inside a bit is were the hose is shut off due to swelling. But it wasn't deep enough that a 1/16" drill bit couldn't reach.

Can't find pic. Even had my wife looking because she took it. It was a few years back, but we save everything, Well almost it appears. Like here is the picture of the plugged hose that got us stranded. here is a picture of Dan drill out that hose. She was snapping pictures like crazy capturing the fun we were having on our trip in sweltering heat stuck in a plaza.

If you crack bleeders loose and they have pressure something is wrong. Either the rubber hoses collapsed or master cylinder is faulty. And with history with this, I have new lines on my list. Truck just turned 10 years old and it is a fear factor of being stuck in Virginia again on vacation.

 

From your vehicle descriptions, I would guess that both were rear drum types. Yes? Not that it should make a difference, fluid pressure is fluid pressure, blockages are blockages.

I wonder if these problems are caused by "faulty" crimps, or are brake hose fittings designed so that this can specifically (though not intentionally) happen?

Pop

 

Pop, Dan, the rubber hose collapses when the inner liner of the rubber separates from the outer cover and forms a valve akin to the valves in a heart. The reason they are usually near the crimps is because the inner liner of the fitting along with the external crimped collar cause the inner rubber liner to form a crease where it eventually fails after repeated pressurization/depressurization cycles. The cure is to get teflon-lined stainless steel braided flexible brake lines to replace the rubber ones.

 

Motorhome had Drums on the rear. yup I just looked up the year that i had. 1992 Ford E350 chassis

Sunbeam had rotors. Was an option for that year and both hoses were shot in the front. That car sat a lot because it scared me to drive. Drove terrible. Tube tires. 66 sunbeam alpine. = Cool but Junk.. Once car i wasn't upset to see go

I know the Sunbeam is crazy old. So a lot of weird things happen. But the motorhome was at a year we can relate to. I find it weird that it happened to me twice and not much talk about it, but you do find it with google search with the brake hose swollen causing one caliper to be pressurized or both. And using a bleeder to release the pressure as a cure to the symptom.

EDIT> yup. teflon-lined stainless steel braided flexible brake lines. On my list of "to do's" Thanks, Leonard.

 

Are DOT-approved Teflon replacements available?

I ask about the approval because if an accident occurs they look at everything to find a reason to disallow insurance coverage, especially of it's a high-profile incident.

I asked my favorite hydraulics shop about this very thing a couple of years ago and was told they would only make them "for off-road use only".

Pop

 

Pop, any custom-made hose from a hydraulic shop will NOT be DOT approved even if they are crimped fittings because of the rules behind DOT approval (testing to failure of x number of samples from a batch etc etc). Skyjacker claims their stainless/teflon brake lines are DOT approved. Goodridge should have some too but I have not been able to find any Superduty applications yet.