bleeding brakes,,,3 of 4 normal,,,, but the 4th??????

[harmony]

I bleed my brakes today on my 48 Chrysler Windsor.  Starting with the rear, right, then rear left, using the Mityvac and it worked fine and it didn't take long to get the air out.  Then I moved to the front right since it was the next furthest from the master cylinder.  It has 2 wheel cylinders and I started with the top one.  I hooked the Mityvac up as usual by putting that right angle rubber boot on the bleed screw and built up a bit of vacuum and it held.  Then I cracked open the bleed screw, and I was puzzled.  Nothing came out. gradually I could see tiny bubbles and a trickle of brake fluid.  I pumped up a but more vacuum to around 20 and it was still holding.  After about a minute of watching basically nothing happen there was maybe less than an 1/8 of brake fluid in the container.  I closed it off and tried the bottom wheel cylinder and I got the same results.  Then I went to the front left and on both wheel cylinders I got the normal results.  Filling the container with air and brake fluid in about 10 seconds.   Then refilled rthe master cylinder and did it again.    

I have lots of hard brake pedal and it doesn't fade.  The reason I bleed the brakes was because I just replaced the rear seals so I had to disconnect the brake lines back there to remove the backing plates.  Before I started the wheel seal project I was using the car regularly and I had no issues of the brakes pulling to one side or having to pump them or anything like that.

 

So I'm curious about what's going on and I'm wondering if anyone has had this issue?  Before I bleed the brakes, since the car is up on 4 stands it was a good time to repack the front wheel bearing and as a normal procedure I always check the wheel cylinders and brake mechanism for oddities whenever I'm doing that and everything looked fine.  I may take it for a short test ride to see if it stops normally, or firstly, I might disconnect the rubber line feeding the top wheel cylinder to see if it might be blocked.  I pulled out the bleeders and they were both clear and I looked in the wheel cylinders as best I could with a mirror and they both seemed to be clear.   As I said the car has been stopping just fine.

[kencombs]

It's possible that the flex line to that wheel has begun to de-laminate inside.  The loose pieces could be stopping the flow..  Only way to tell is to unhook it,preferably completely remove to check it out.

[harmony]

46 minutes ago, kencombs said:

It's possible that the flex line to that wheel has begun to de-laminate inside.  The loose pieces could be stopping the flow..  Only way to tell is to unhook it,preferably completely remove to check it out.

Yeah that was probably going to be my next step.  Even though it looks good on the outside, it makes sense that since both wheel cylinders won't bleed that it has to be something before it.  If it's not that hose, then the next place is that fitting at the brake light switch.  I'll just start working backwards I guess.

[Veemoney]

You get a lot more pressure pushing the brake pedal pushing fluid through the line then you would with the vacuum tool using air. That may be the reason the brakes seemed to work well during use previously. If you have someone to help you could try pumping the pedal up and have someone open and close the bleeder to see if that pushes fluid and if anything else comes out of that side. 

 

[harmony]

12 minutes ago, Veemoney said:

You get a lot more pressure pushing the brake pedal pushing fluid through the line then you would with the vacuum tool using air. That may be the reason the brakes seemed to work well during use previously. If you have someone to help you could try pumping the pedal up and have someone open and close the bleeder to see if that pushes fluid and if anything else comes out of that side. 

 

My thoughts exactly as I was scratching my head when it happened. But there just wasn't anybody around at the time.  I actually prefer the old school way of bleeding the brakes with 2 people.  I even was trying to rig something up that would keep constant pressure on the brake pedal similar to a persons leg pressure while I loosened the bleeder.  I was also thinking about setting up my camera pointing it at the bleeder, then hit video, then go apply pressure on the brake pedal, to see what happened.  If nothing happened, I'd try removing that rubber flex hose and try again.  

[Bryan]

If the rubber hoses have been on there several years I would replace them anyway.  I have the same bleeder as you, my brother and I were using it on a Saturn.  It should work the same on both sides.  I also saw a video that hose clamps can sometimes be too tight and restrict the hose.  One thing I learned, but not applicable here, that on any wheel cylinder or caliper, the bleeder should be on top. That's why some parts are designated Right and Left.  Glad these cars don't have powered brake pumps with individual circuits like that Saturn.

[jfish]

I noticed on this page the brakes technical section says when bleeding the front brakes do the top cylinder first.

But the service manual says to do the bottom cylinder first.

[Tom Skinner]

Harmony,

jfish is correct. Bleed bottom wheel cylinders at the front first or you will not achieve full brake fluid flow (without bubbles) at the tops, or a firm brake pedal.

Other than that you may have blockage in an old flex line (at least that doesn't cost anything to disconnect and check). Don Coatney a few years back sent me an extra Master Cylinder Lid with a cut out for a Brake Fluid Bottle to attach to. I fill it with DOT 3 screw it into the top of my M.C. and commence to bleeding the brakes using a small bottle and magnet and hose. This is achieved with keeping the bottle above the wheel cylinder (basically gravity fed) while my wife, kid, or friend pumps the pedal slowly to the floor and holds it there numerous times until the fluid comes without bubbles and clear/new color - not dark or dirty). In this way a nice hard brake pedal is achieved.

If minor adjustments are called for at the cams I then do that as well. Brakes are like new after this procedure.

Tom

[harmony]

I found the problem.  This wheel cylinder is the top one.  The bottom one was also seized but it didn't look as bad, just a ring of rust around the edge of the piston.  What I can't figure out is why the car stopped so "normally"  It didn't pull to one side or act up at all.   I checked the fluid level from time to time and it was fine.  I never saw signs of any leakage.   As you can see by the casting, it's not rusted.  I was told when I bought the car a few years ago that it had a recent brake job and all wheel cylinders were replaced.  The rear brake lines were replaced at that time, but not the front.  So now is as good a time to replace them, while I wait for new wheel cylinders to arrive.

[Andydodge]

Yep, thats replacement time, but I'd try pulling the cylinder apart and check whether the cylinder maybe able to be honed or sleeved to be kept as a spare or if need be reused......if so then I'd not keep it assembled but coat with a rust preventative and trust that keeps the bore clean ........andyd

[harmony]

2 hours ago, Andydodge said:

Yep, thats replacement time, but I'd try pulling the cylinder apart and check whether the cylinder maybe able to be honed or sleeved to be kept as a spare or if need be reused......if so then I'd not keep it assembled but coat with a rust preventative and trust that keeps the bore clean ........andyd

I could be wrong, but I don't think you can with these front half cylinders. There is no way to get the piston out.  I tried blowing air in from the bleeder hole and from the other hole that feeds the other cylinder with my compressor, but the piston didn't budge.  I suppose I could soak them in ATF for awhile and see what happens.   

[Veemoney]

I seen a lot worse with pitting and they still cleaned up well. Try cleaning a bit and pushing it in and then use air in the fluid port working it back and forth. Careful as they can shoot out when applying the air. I have that style on the rear of my truck.

[oldodge41]

If the car seemed to stop normally with one front wheel not braking at all, chances are good the other front wheel wasn't doing much either. I would be checking the cylinders on the other front wheel very closely too. With one front wheel braking and one not braking I would expect a significant pull to one side when braking. If all you had was rear braking, your new normal will feel much better.

[harmony]

3 hours ago, oldodge41 said:

If the car seemed to stop normally with one front wheel not braking at all, chances are good the other front wheel wasn't doing much either. I would be checking the cylinders on the other front wheel very closely too. With one front wheel braking and one not braking I would expect a significant pull to one side when braking. If all you had was rear braking, your new normal will feel much better.

I've ordered all 4 wheel cylinders.  I'm replacing all the brake lines as well.  I'm thinking that the brake lines are original because they have the spring sleeve around them in vulnerable places.

[harmony]

11 hours ago, Veemoney said:

I seen a lot worse with pitting and they still cleaned up well. Try cleaning a bit and pushing it in and then use air in the fluid port working it back and forth. Careful as they can shoot out when applying the air. I have that style on the rear of my truck.

The forced air from my compressor didn't budge the piston on the one in the picture.  However I could see slight signs of bubbles or air coming out around the perimeter of the piston on the other one.  Out of curiosity, I'll try filling the cavity with ATF and make  a wood dowel and try squeezing slightly after awhile with a clamp, then a bit of air from the other side and back and forth.  My curiosity is how moisture got in there to create that much rust, in light of the fact that I was driving her almost daily.  As I mentioned the wheel cylinder casting looks almost new.   ????

[Dan Hiebert]

10 minutes ago, harmony said:

I've ordered all 4 wheel cylinders.  I'm replacing all the brake lines as well.  I'm thinking that the brake lines are original because they have the spring sleeve around them in vulnerable places.

At first glance, that wheel cylinder doesn't look all that bad, and should clean up well.  They'll make good spare parts.  What you described when bleeding that one does not sound like a problem with the wheel cylinders, though.  That's exactly what was happening with the right rear when I bled the brakes on my VW this spring.  In my case it was that the flexible line had deteriorated.  I did not have noticeable differences in the wheels braking either, but that one just wouldn't bleed.  Always a good bet to replace / rebuild brake systems with an unknown history.

[harmony]

3 hours ago, oldodge41 said:

If the car seemed to stop normally with one front wheel not braking at all, chances are good the other front wheel wasn't doing much either. I would be checking the cylinders on the other front wheel very closely too. With one front wheel braking and one not braking I would expect a significant pull to one side when braking. If all you had was rear braking, your new normal will feel much better.

I had the front wheels adjusted up pretty well, I'd gradually adjust front and back adjuster gradually so they grabbed equally.  Then back them both off ever so little.  They would free spin about a half rotation.  I had tested them on a gravel driveway a few times and then looked at the skid marks on the driveway to check that they grabbed at the same time. 

[TodFitch]

34 minutes ago, harmony said:

I've ordered all 4 wheel cylinders.  I'm replacing all the brake lines as well.  I'm thinking that the brake lines are original because they have the spring sleeve around them in vulnerable places.

The spring sleeve material is available though it would take me a little time to find the catalog/website(s) I noticed them in. So it is possible that the lines were replaced. That said, it is pretty unlikely that whoever replaced the tubes would have put new but original style spring sleeves on them so you are likely correct.

 

Brake tubes usually rust from the inside out so if there is any question as to age or condition they should be replaced.

[Young Ed]

1 minute ago, TodFitch said:

The spring sleeve material is available though it would take me a little time to find the catalog/website(s) I noticed them in. So it is possible that the lines were replaced. That said, it is pretty unlikely that whoever replaced the tubes would have put new but original style spring sleeves on them so you are likely correct.

 

Brake tubes usually rust from the inside out so if there is any question as to age or condition they should be replaced.

Some of the 25' rolls of copper nickel come as a kit with the coiled armor. 

[Sniper]

1 hour ago, TodFitch said:

The spring sleeve material is available though it would take me a little time to find the catalog/website(s) I noticed them in

 

Inl9iine tube sells it

 

https://www.amazon.com/Tube-Spring-Tubing-Protectant-Stainless/dp/B07KX6Y22C

[harmony]

I'm inclined to think that the brake lines are original.  As you all know the spring is tight around the brake line, meaning it has to be slid on before the ends are put on and flared.  The brake line that goes from the differential to the master cylinder is just under 7 feet long, one piece and the spring area is where it goes under the frame then comes right back up on the other side and runs on the inside of the frame and it's held on by those spring steel clips.  No doubt protecting it from gravel, or whatever.  On the differential side of that brake line before it goes under the frame, it is fastened to the frame right beside the fuel line with a 3/8" bolt and 2 steel clamps ( can't remember the name of those things, these days they are plastic) one for the brake line, one for the fuel line, which is also covered in spring only larger.  It all looks very factory.

The car doesn't look like it has very been restored.  However the brake job may have been done by a vintage car enthusiast and did a good job of keeping it authentic. 

[Veemoney]

10 hours ago, harmony said:

 My curiosity is how moisture got in there to create that much rust, in light of the fact that I was driving her almost daily.  As I mentioned the wheel cylinder casting looks almost new.   ????

You likely had Dot 3 or 4 brake fluid in the system. Both fluids absorb moisture from the air over time. Depending on if your car sits outside or in humid conditions this  can take less time than in dryer climates or inside storage. It is common with the saturation of the oil over time that water absorbed in the oil gets to a density in the oil where it starts rusting the carbon steel. Maintenance to prevent this issue is flushing old waterlogged fluid out with new fluid based on fluid recommendations for this. 

 

There is some discussion on brake fluids on this site here concerning brake fluids  DOT 5 - Technical Archives - P15-D24.com and Pilot-house.com

[harmony]

4 minutes ago, Veemoney said:

You likely had Dot 3 or 4 brake fluid in the system. Both fluids absorb moisture from the air over time. Depending on if your car sits outside or in humid conditions this  can take less time than in dryer climates or inside storage. It is common with the saturation of the oil over time that water absorbed in the oil gets to a density in the oil where it starts rusting the carbon steel. Maintenance to prevent this issue is flushing old waterlogged fluid out with new fluid based on fluid recommendations for this. 

 

There is some discussion on brake fluids on this site here concerning brake fluids  DOT 5 - Technical Archives - P15-D24.com and Pilot-house.com

Yes I'm using Dot 4.  I'm in BC, and yes since I've had the car it has been outside year round under a cover.  ( I have a shop to keep it in now) We have lots of rain during the winters here so that could account for a lot of moisture in the air.  So what are we talking about for the time frame of changing the fluid, yearly?  

[harmony]

6 minutes ago, harmony said:

Yes I'm using Dot 4.  I'm in BC, and yes since I've had the car it has been outside year round under a cover.  ( I have a shop to keep it in now) We have lots of rain during the winters here so that could account for a lot of moisture in the air.  So what are we talking about for the time frame of changing the fluid, yearly?  

That link is a good read, thanks.   I'm thinking I might stay with Dot 4.  Even though with the 4 new wheel cylinders on the way, I'd still have to replace the 4 rubber flex lines, and I'd have to get new rubber boots for the rear wheel cylinders.  The flex lines wouldn't be a problem. just an expense, but I don't think any of the vintage MoPar suppliers offer just the rubber boots.  I'm wondering if they are a generic size on the rear.  

[harmony]

19 minutes ago, harmony said:

Yes I'm using Dot 4.  I'm in BC, and yes since I've had the car it has been outside year round under a cover.  ( I have a shop to keep it in now) We have lots of rain during the winters here so that could account for a lot of moisture in the air.  So what are we talking about for the time frame of changing the fluid, yearly?  

I just went back to the link and read what I missed the first time and that is, dodgeb4ya recommends changing dot 3 and 4 brake fluid every 2 years.  So I'll probably do it every year. 

Edited December 11, 2021 by harmony