Brake Help Needed

[rb1949]

Drats, couldn't make it to the car show today. Brakes seemed to be working OK, but now right front is acting up. Not just a slight pulling to the right. What might be causing those shoes to jump out, GRAB the drum, lock up and squeal the tire? Have tried multiple adjustments with no success. Both front cylinders are new, no leaks. Shoes & drum OK. Springs and hardware in tact. New rubber hose.I'm baffled as to what is going on in there. Back up in reverse, hit the brakes, and everything is fine. Hoping some of the experienced wizzards here may have a clue to help resolve this issue. Have no idea why this one front would be grabbing so badly. Brake system is stock, the 49 Chrysler..

[Don Coatney]

And the service manual says....

 

[rb1949]

Perfect, my manual says the exact same thing as Don's image. Will be checking again today. Might need a bigger hammer. Frustrating when things appear correct but they are not.

[1949 Wraith]

Have you checked how warm your wheel hubs are after you have done some braking? They should all be about the same if they are all working together. If your car is pulling to the right possibly your front left brake is out of adjustment and  not applying the proper braking. The front left hub will be noticeably cooler if it is not creating braking friction.

[rb1949]

Sorry, to dangerous to be driving, even 1 mile to the show. And if it stayed locked up, I would be stuck. Testing is done in the driveway. Maybe around the block. But yes rechecking the left is on the agenda. When a helper is available want to try a re-bleed to make sure lines are open.

[desoto1939]

Did you play with the eccentrics and make any adjustments?  Did you loosen the castle nut on the back of the backing plate for either of the eccentric and if you did then did you retighten the castle nut and also put the cotter pin back into the slot.  I was getting a rumble and pul on one front brake and I discovered that the one eccentric locknut was not tight enough and this cause the issue.

 

I have found out that sometime the new brake lining is hardening and get slick and this cause also cause issues and the lining glazes.  clean the shoes with some brake cleaning spray think it a CRC product.  Check the drum to make sure there is no brake dust.  Just some suggestions.

 

Rich HArtung

desoto1939@aol.com

 

[soth122003]

I have a similar problem on my front right. For mine it is the shoe had been soaked in brake fluid and even after cleaning it well, it still sticks and grabs after not driving it for a while. Also the inside drum will lightly rust up from not being used. When I back up, I ride the brakes to clear this and then going forward the brake will still grab and catch until it clears the light rusting and wears the surface of the pad back to smooth. This usually takes a couple of slow braking stops to clear, then the brakes work normally until I let it set for about 3-4 days of not driving.

Joe

[dale]

I had this trouble once and found the shoe lining had gotten brake fluid on it.   Only solution is to throw them out and install a new set.   You cant clean them..

[dale]

Maybe replace the wheel cylinders ?

[rb1949]

Not logical to be thinking about another new pair of cylinders. But **** happens. My startup procedure mentioned good shoes, clean drums, no leaks. Adjusters are working but don't help the problem. No change by tweaking the left. This is way more than a minor pull to the right. Squealing the rubber at 5mph. Thought I was onto something with an anchor bolt out of line, so put in position, but luck refuses to come my way. Multiple adjustments are achieving nothing. Nothing was done to the brakes when this started the other day. Disgusted and confused.

[1949 Wraith]

When the car was braking properly, what work did you do on the cars brakes? Is the car braking a lot worse since you did some work on the brakes? Look at the things you changed since it worked properly.

Almost sounds like a collapsed flexible hose not allowing the fluid to return, locking up the brake on the right side. But it sounded like you replaced both hoses. With the wheel off the ground does it turn after you apply the brakes, or does it stay locked up? If it locks up, loosen the bleeder on that side and if that allows the wheel to unlock the flexible hose has collapsed and needs replacing

 

[soth122003]

Gotta go with Goat on this one, Sounds like a hose or line that is partially collapsed. It will let fluid through but is slow on the release. If the front left is good, then I would pull the right hose and check it. Even the new one (from China esp.) can be bad just from sitting on the shelf. I would also check the wheel cylinder as well and the return spring (might have broken after installation). For a one wheel problem like this, it is one of those 3 things.

[rb1949]

Agreed, it's a one wheel mystery with not many parts involved. Only work was replacing flex hoses 2 months ago. After applying brake pedal, wheel still spins freely. Which should also indicate cylinders are retracting properly(?)  What else do you look for with cylinders without removing them. Mounting hardware all good. Why is all the pressure jamming that right shoe (shoes) out so quickly. Doesn't seem possible that one side would get more pressure than the other. The old trick is to start replacing parts. Ugh. If it comes to shoes, probably should not replace just one side? Exhausted with all this jacking up and down and pulling wheel. Those ol' tires are heavy!

[1949 Wraith]

3 hours ago, rb1949 said:

 Only work was replacing flex hoses 2 months ago. 

I would look at these parts first, especially on the side that locks up.

[Don Coatney]

Also peel back the rubbers on your wheel cylinders and look for leakage and or rust. The wheel cylinders on my car were rusted up and the brakes pulled to the right. Replaced them and all is well now. I also replaced the shoes and turned the drums.

[soth122003]

If you apply brakes and they release just fine, It probably isn't the lines or hose. Nor the return spring either. The cylinders just apply pressure and the spring pulls the shoes back. If you drive the car slow, apply brakes lightly and the right stops really suddenly but releases just as quickly, I'd say the shoes are the culprit. They can look good, but after being soaked in brake fluid, they just grab.

Joe

[rb1949]

Ah, 92° today, great work on the jalopy weather. Even though you don't know what you're doing or why. Jacked 'er up and pulled wheel again. Trying to follow all your suggestions, that we understand what was going on.The right front would GRAB first, squealing the tie, but then also release. No cylinder leaks. Lucky to have assistant stop by. We did a re-bleed of all 4 front cylinders. Nothing but clear fluid emerged. Pedal was good and solid. Agreed that shoes did not look contaminated with something. Maybe looks are deceiving. So I made a judgement based on soth's comment above. If the system is working, focus on the shoes. Sprayed the shoes good with some ancient brake cleaner, then scuffed them up with rough sandpaper. Put drum back on and did an adjustment. Installed wheel and dropped it down. Highly anticipated tire squeals in the driveway test. My God, the ol' jalopy stopped ...... perfectly straight and smooth. Did that 4-5 times, normal slow stop or hitting the pedal hard. Forward & reverse. So, is it because I currently have a "clean" shoe? If the show is contaminated, the oils will soon rise back to the surface and the problem will come back. Need to go for a short ride and see what happens when they heat up a bit. Feel better that SOMETHING has helped this issue without major investments. Will report back on what may happen. Thanks for all the advice. Get this buggy back on the road, maybe somebody will make me an offer?

[soth122003]

The brake cleaner is at most a temp solution. You will probably experience what I go through now. The car brakes fine when you drive it daily, but when it sets for a few days the contamination will rise to the surface again. When you drive the car the brake will grab the first few times you use them and then will probably work fine. Or they might not. On mine the right side will grab the first few times, so I lightly ride the brakes, then after the first couple of stops they work great and even until I let it set for 3-4 days.

Best bet is change the shoes on both sides and be worry free. Me...I am a cheap SOB.  Your choice. and glad I could help.

Joe

 

[rb1949]

Jumped in and took a ride to the local weekly cruise in. Just a drive by, didn't stay. The jalopy brakes performed well. Still happy for the moment. Agreed, this procedure which made an improvement is a watch and wait deal now. The shoes may be temporarily clean. Will be waiting and feeling for any changes which could indicate any contamination is still there, and the problem could return. Then it's time to replace shoes. Already checked, shoes are not available local. On line prices are pretty consistent from various sources. I'm a Mr. Frugal too, same as that word cheap. Those big, tight anchor bolts seem to be the biggest part to remove. Question: what is the purpose of that horse-shoe clip on the anchor bolt? I'll recheck a diagram. Too soon old and too late smart. Exhausting my bones to keep the 49 moving.

[Don Coatney]

Check with these folks for brake shoe relining. They are reasonably priced, fast service, and reliable. Many forum members myself included have had good results dealing with them.

[Young Ed]

2 hours ago, rb1949 said:

Jumped in and took a ride to the local weekly cruise in. Just a drive by, didn't stay. The jalopy brakes performed well. Still happy for the moment. Agreed, this procedure which made an improvement is a watch and wait deal now. The shoes may be temporarily clean. Will be waiting and feeling for any changes which could indicate any contamination is still there, and the problem could return. Then it's time to replace shoes. Already checked, shoes are not available local. On line prices are pretty consistent from various sources. I'm a Mr. Frugal too, same as that word cheap. Those big, tight anchor bolts seem to be the biggest part to remove. Question: what is the purpose of that horse-shoe clip on the anchor bolt? I'll recheck a diagram. Too soon old and too late smart. Exhausting my bones to keep the 49 moving.

The horseshoe clip is how you remove the shoes.

[Niel Hoback]

Spread the clip ends, unhook the spring and pull the shoe off. 

Do not loosen the anchor bolts. They are eccentric and the major shoe adjustment you don't want to get into.

[rb1949]

Thanks on the clip tip. Makes the possibility of a shoe change sound better. Might as well change my socks too.

edit: And the tip on shoe reline. Only drawback is the downtime, not getting the parts today and installed in 1-2 days.

Edited September 7, 2016 by rb1949

[William Davey]

6 hours ago, Niel Hoback said:

Spread the clip ends, unhook the spring and pull the shoe off. 

Do not loosen the anchor bolts. They are eccentric and the major shoe adjustment you don't want to get into.

If you reline or  replace the shoes, you'll almost certainly be into a major brake adjustment (as opposed to minor). In that case you'll have to adjust the large eccentric bolts anyway. You may want to read up on that procedure BEFORE you jump into this job. It's not overly difficult, but it can be time and patience consuming. Some on the forum advocate use of a special tool (Aamco 1750) while others have done without.

[rb1949]

Long before this episode I downloaded the 'instructions' for brake change and the 2 special tools recommended. Discussions vary on the procedure, with tool, with home made tool, and without tool. All seem to have accomplished the goal. PS: the jalopy was still stopping straight today.

edit: Extensive reading also found another possible tip regarding collapsed flex lines. If one is experiencing excessive stopping power on one side, check the flex hose on the OPPOSITE side. If bad, the pressure is all going to one side. Makes sense.

Edited September 8, 2016 by rb1949