Question about the brakes

[47heaven]

I've noticed lately that when I have to stop the brake pedal almost goes to the floor. The car will stop, but I have to pump a couple times to get brake pressure and keep the pedal from touching the floor. I checked the brake fluid, and it's fine. There is no sign of leakage from the master cylinder. So I'm assuming that it may be air in the line, but who knows?

[55 Fargo]

I've noticed lately that when I have to stop the brake pedal almost goes to the floor. The car will stop, but I have to pump a couple times to get brake pressure and keep the pedal from touching the floor. I checked the brake fluid, and it's fine. There is no sign of leakage from the master cylinder. So I'm assuming that it may be air in the line, but who knows?

Darren the lockheed brakes need periodic adjustment too, and you have hills in your area correct?

Air is alo possible, if it is spongy, do you get a fuller peddle if you pump up the brakes.

Possible remedy, do proper brake bleed, adjsut brake shoes correctly, or if all else fails, buy a disc brake coversion kit from Old Daddy, which will be useful in your Southern California trafic and elevations.........Fred

[47heaven]

Yes, Fred, the pedal seems to have more pressure when I pump it a couple times and doesn't touch the floor, but will slowly sink. I will do a brake bleed on it, and I'm sure they are up for adjustment, since it's been almost a year since new shoes were installed in the front. Let's see if this works and I'll get back to you. Thanks!

[desoto1939]

It sounds as if the brakes need a minor adjustment to get the linings closer to the drum.

remember these old system do not have automatic adjusters like the cars of modern times. As the lining wears on the shoe the arc has to travel further when you push on the brake pedal.

JAck the front of the car up and support the car. You willhave two cams for the upper adjustments. Pull one to lock the shoe against the drum then backoff and spinthe wheel so you have a little bit of drag. Then do the other shoe.

Then pump the brake pedal to get the brake fluid into the line since you moverd the shoes outward. Then do the other side.

Test to see if the pedal is now firmer. Then jack up the rear and do each drum inthe back.

Let us know what happens. Also go to the technical section on brakes to review the use of the miller and Ammco tool brake adjustments.

I did this demo at last years AACA convention in Phila, PA

rich hartung

desoto1939@aol.com

[Don Coatney]

You have air in the system and need to bleed the brakes.

If after a couple of pumps you get good pedal your brake adjustment is fine.

If your pedal slowly drops to the floor when you apply continous pressure then your master cylinder has an internal leak.

You should also inspect the entire system for leaks as a leaking system will introduce air.

Edited January 20, 2010 by Don Coatney

[cwcars88]

You said the pedal will slowly sink. Sounds to me like the master cyclinder needs to be rebuilt.

[Plymouthy Adams]

IF..you press the pedal and it goes low but is firm and does not continue to fade...and while it may be low pedal but functional AND quick successive pumps gives you a firmer pedal but returns back to the same condition next application..I would say you are in line for a brake shoe adjustment to compensate for the displacement of fluid to expand the shoes against the drum.

I would not not think air is your problem as the pedal is constant as I read your post..there is no sign of leakage so I would also assume the cylinders are not leaking and if there is no sign of fluid at the rear of the master then the system integrity is good. The fact that light pedal pressure will maintain your brake condition without further travel down toward the floor..then your master is not by-passing internally.

[47heaven]

IF..you press the pedal and it goes low but is firm and does not continue to fade...and while it may be low pedal but functional AND quick successive pumps gives you a firmer pedal but returns back to the same condition next application..I would say you are in line for a brake shoe adjustment to compensate for the displacement of fluid to expand the shoes against the drum.

I would not not think air is your problem as the pedal is constant as I read your post..there is no sign of leakage so I would also assume the cylinders are not leaking and if there is no sign of fluid at the rear of the master then the system integrity is good. The fact that light pedal pressure will maintain your brake condition without further travel down toward the floor..then your master is not by-passing internally.

Tim...what you say makes good sense, just like what everyone else has said. I think I will take it in for adjustment, since I have a lifetime free adjustment on the brakes from the place that did the rebuild on the system. If that solves the problem, then I'm good to go. If not, then I will proceed with the other options mentioned. I drove the car in heavy rain yesterday and when the brakes got wet in the front it really pulled to one side when the brakes were applied. I'm assuming because that was wet, of course.

cwcars88...the master cylinder was rebuilt and resleeved two years ago. Also, no leaks are seen from it.

[desoto1939]

Since you are taking the car back to the shop to have them adjust the brakes I would suggest that you ask them if you can go into the bay area with them so that you can watch what they are doing. This way you will learn what they are doing and then you can always make an adjustment if you ever had to do one.

Learning from a mechanic is great and remember knowledge can never be taken away from you. You paid for the service originally so get your moneys worth. This is just my 2 cents worth.

Case in point, when ever a contractor is doing work at my home I watch and ask questions to get some knowledge ad so I can do the same job in another room if need or make an emergency repair.

The more that you know about your car the more you will feel comfortable when taking the car on trips and long drives away from your home base.

Rich HArtung

[47heaven]

Since you are taking the car back to the shop to have them adjust the brakes I would suggest that you ask them if you can go into the bay area with them so that you can watch what they are doing. This way you will learn what they are doing and then you can always make an adjustment if you ever had to do one.

Learning from a mechanic is great and remember knowledge can never be taken away from you. You paid for the service originally so get your moneys worth. This is just my 2 cents worth.

Case in point, when ever a contractor is doing work at my home I watch and ask questions to get some knowledge ad so I can do the same job in another room if need or make an emergency repair.

The more that you know about your car the more you will feel comfortable when taking the car on trips and long drives away from your home base.

Rich HArtung

You are right, Rich, but some places, for insurance purposes, do not allow customers in the bay area, such as the place I will be taking my car to have the adjustment. They have a waiting room for the customers.

[hillbilly jack]

does this shop specialize in old cars? if not, how do they know how to set up this system?

[Don Coatney]

You are right, Rich, but some places, for insurance purposes, do not allow customers in the bay area, such as the place I will be taking my car to have the adjustment. They have a waiting room for the customers.

If it were me I would find another shop or make it known that I want to see what is going on. But that is just me. If you are comfortable with this go for it. While you are sitting in the waiting room observe how many customers are invited to take a look into the bay to make a repair decision.

[47heaven]

If it were me I would find another shop or make it known that I want to see what is going on. But that is just me. If you are comfortable with this go for it. While you are sitting in the waiting room observe how many customers are invited to take a look into the bay to make a repair decision.

I wish it was that easy, but there are not many shops around here locally that specialize in old cars of our vintage or have a mechanic that understands are cars. I would love to see how it's done, but if I'm directed to wait in the waiting room, then I will have to wait there with the others who are not allowed to go into the bay area, as well. If they have a question about the car that they want to make a decision on, then most likely they would call me in to show me.

[47heaven]

does this shop specialize in old cars? if not, how do they know how to set up this system?

Yes, they do. That's why I had them do the brake system for me because all they do are brakes.

[Reg Evans]

does this shop specialize in old cars? if not, how do they know how to set up this system?

I'll have to agree with that statement. Do they have an Ammco 1750 to get the shoes centered ?

[blueskies]

I...I would love to see how it's done...

If you have a jack, and a wrench, it would take you about 10 minutes to make a minor adjustment of the brakes. This is assuming they set up the shoes with the AMMCO gauge in the first place.

If they don't have the AMMCO tool, and know how to use it, your brakes will never work as good as they did from the factory. It is the only way to get the shoes centered in the drum. This can not be done by "feel" (If Norm had a dial-up connection from the afterlife, he'd be disagreeing with me now... ). The shoes are not self centering, I wonder if the shop knows this?

Pete

[Dodgeb4ya]

If you have a jack, and a wrench, it would take you about 10 minutes to make a minor adjustment of the brakes. This is assuming they set up the shoes with the AMMCO gauge in the first place.

If they don't have the AMMCO tool, and know how to use it, your brakes will never work as good as they did from the factory. It is the only way to get the shoes centered in the drum. This can not be done by "feel" (If Norm had a dial-up connection from the afterlife, he'd be disagreeing with me now... ). The shoes are not self centering, I wonder if the shop knows this?

Pete

Also to do these lockheed brakes faster and 100% right you also need to know each drum diameter to machine arc the shoes to fit the drum so they can be properly adjusted to the drum which =100% shoe contact= firm high pedal. Not a lot of shops use the shoe arching machines anymore because of the dust hazard and generally just are not required now days. I always arh my shoes before assembly-have my own machine.

Bob

[desoto1939]

If they had used the Ammco brake gage to adjust the shoes correctly several years ago then the lining has worn down since you have been driving the car.

In most case as I had stated in a previous post you probably only need to perform the minor adjustment.

Please call me and I can walk you throught this. I have the Ammco tool and alsothe Miller MTC19 tools. Also did you go to the Tech Archive and look at the posting on the brake tools that I also had posted.

Minot Brake adjustment is all most a yearly thing with this older cars and if you learn to do this you willsave money and get to know your car. This is a very simple job to do. If you can turn a wrench then you can do the minor brake adjustment.

Rich Hartung

Desoto1939@aol.com

484-431-8157

[Don Coatney]

If I correctly read the initial posting on this thread that the pedal goes to the floor on the first push but returns to a higher position after pumping then the problem is air in the system, not adjustment.

[Dodgeb4ya]

If I correctly read the initial posting on this thread that the pedal goes to the floor on the first push but returns to a higher position after pumping then the problem is air in the system, not adjustment.

Yep, Once again a thread got derailed.

[Young Ed]

Don not always so. I thought I had air in my system too because my truck was doing that. Bad pedal but one pump would make it work better. Dad insisted I try adjusting them and that fixed it. Pedal was perfect the rest of the summer. Didn't make sense to me either but it worked

[Plymouthy Adams]

It works because the quick pumps diplace the piston and push the shoes against the drum...once you relase the brakes however you are back to square one and the low pedal..low but firm..adjustment..pumping the brakes with air will yield a tight pedal that will remain for a short time...if they go down after a few minutes...the air that has been diplaced by busting the bubble into smaller parts spread about the fluid will again reunite to the umcompressable air bubble..

[Captain Neon]

I wish it was that easy, but there are not many shops around here locally that specialize in old cars of our vintage or have a mechanic that understands are cars. I would love to see how it's done, but if I'm directed to wait in the waiting room, then I will have to wait there with the others who are not allowed to go into the bay area, as well. If they have a question about the car that they want to make a decision on, then most likely they would call me in to show me.

If a repair shop is willing to allow a customer in to the shop area to authourise repairs then the whole argument of insurance liability goes right out the window. There is no exception to the Personal Protective Equipment policies simply if a visitor is only going to spend a few minutes out on the floor.

They take just as much risk in allowing a customer out on the floor for a minute or two to authourise a repair as they would to allow you to watch them work. They may not realise this, or they believe that the risk is less, but a customer is just as likely to get injured to authourise a repair as supervising repairs.

While the insurance disclaimer is true of most shops, I don't do business with any shop that wants to sell me a decarbonising treatment. A good shop will just tell me that they observed or suspect carbon build-up and then how to remove it myself: long trip at highway speeds or driving around town in a lower gear.

I also don't have a lot of patience for any one that wants more than $40 for an oil change. The experienced ASE mechanic is no more qualified to change oil than the 16 year old kid at Jiffy Lube.

BTW, I change my own oil because then I KNOW that the oil got changed. I've seen too many hidden camera investigations where cars brought in for oil changes never get their oil changed or vehicles are sabotaged to justify more repairs. Repair shop logic: any one that can't change their own oil probably doesn't know any thing and is an easy mark. This is why teenage and college-age girls are often seen as easy marks by repair shops. Also, if the girl is pretty they want her coming back often or at the very least staying in the waiting room as long as possible. I have yet to find a repair shop where a pretty girl can't get complimentary shuttle service if she needs to be some where else.

[54Illinois]

So what did it turn out to be? I just re did my brakes and are having the same issue.

[Guest P15-D24]

If I correctly read the initial posting on this thread that the pedal goes to the floor on the first push but returns to a higher position after pumping then the problem is air in the system, not adjustment.

Need to bleed the system. If you pump it and pedal height is OK your brake shoe adjustment is fine. Fix the main problem first before you start chasing of potential issues.