Bleeding Lockheed series 1 brakes

[1949 Wraith]

On my 1941 Chrysler C28 with the Lockheed series 1 brakes I am having issues with proper bleeding

I rebuilt the front brake wheel cylinders and replaced the flex hoses and shoes.  The new shoe brake material is thinner than the old shoes by .05 of an inch, but it does cover the entire shoe on both sides compared to the old shoe that only had 2/3 coverage on the trailing shoe.

I have none of the measuring tools to set the brakes. I did cut a slot on the anchor pins, so I can adjust them when the hub is on. I adjust the lower anchor pin cams to get slight brake drag then adjust the upper cams to get slight drag again. I did this on both front brakes, master cylinder pumps good, using DOT 3 fluid.

I have bled the brakes and tried adjusting the cams to improve brake pedal firmness. The on first brake application the brake pedal is soft and travels near to the floor, a couple of pumps and the braking and pedal travel is acceptable.

You can see in the photo that the fluid hole is half way down the cylinder. I am thinking that there must be some air being trapped at the top of the cylinder when I am trying to bleed?

I was thinking about putting a side of the car in a ditch to get the hole near the top. Hopefully some other easier tips.

Thanks for you help.

[desoto1939]

Did you have the shoe arched to be perfect with the drums. I think you stillneed to use the Ammco Brake 1750 tool to get the perfect adjustment.  You keep saying that you have air in the brake system.  So I am assuming that when you bleed the right rear that you are getting air bubbles in the container that is capturing the brake fluid that has been pushed out from the cylinder and assuming that someone is holding the brake pedal to the floor and then you are tighenting the   bleeder screw on the back of the wheel cylinder.  If you are letting the  pedal come back to the outer  limit then you are having the issue with air coming intot he line from some place. Please explain your total process on what you are doing.

Something is not correct Do you have any leaks in the system the tipping of the car on its side willnot solve the issue.

Your lining thickness should 3/16 and be 2 inches wide. I assume you might have had some wear on the lining these measurements are according to my Wagner Brake catalog. You use the same lining as on my 1939 Desoto the lining number is 1162 which is a number that was used by all brake lining companies.

Rich Hartung  Desoto1939@aol.com  cell 484-431-8157

Edited October 17, 2016 by desoto1939

[1949 Wraith]

Normal bleeding with clear plastic hose. Assistant pumps brakes, release bleeder continue through all 4 corners until no bubbles. No leaks.

Brake peddle still feels soft initially, but builds up pressure and peddle height when pumped a couple of times. It will hold that pressure until you release the peddle. It feels like a system that still has air in it, but the fluid comes out clean with no bubbles. I was wondering if air was being trapped in the upper part of the wheel cylinder above the bleed hole?

Possible too much piston travel due to shallow brake pads and wear on drums?

The shoes were ordered from Andy Bernbaum Auto Parts. These are what they sent me the second time, the first time they sent completely wrong shoes. The brake materiel is definitely thinner than the worn old shoes. The materiel is thinner than the shoes on my 1949 Dodge, 1949 Chevy and 1937 Hudson. I am thinking of just using the old shoes!

[TodFitch]

I've had better luck if the shoes are first shaped to the drum and adjusted before I bleed the brakes. I used sticky back sand paper from my local hardware store: Line the inside of the drum with the paper and rub the shoes against until there is uniform contact. If the shoes are not shaped and adjusted then the shoes will be moving and will be working against you when you press the pedal trying to bleed air out.

I've also had better luck by making up a pressure bleeder using an inexpensive garden sprayer as mentioned in several other threads on this forum. Makes bleeding a pretty quick one man job.

[Dodgeb4ya]

Where is the bleeder screw located... at the top of the wheel cylinder where it should be or in the middle where the hose should be  bolted on?

Shoes must be properly arced and adjusted correctly for a firm pedal.

Normally if the shoes are arced correctly you can leave the anchor cam bolts in the original factory position and just do the minor cam adjustment..turn each shoe out till the drum is locked and carefully back off till just the you have the slightest drag with both shoes on the drum.

After each brake drum adjustment you should apply the brake pedal firmly and recheck each drum/wheel for proper very slight drag.

 

[1949 Wraith]

The bleeder screw is at the top of the cylinder, but inside the cylinder there is only 1 port and it is located half way down the wall of the cylinder. My concern is there is room in the top half of the cylinder for air to be trapped when bleeding?
 

[squirebill]

Hi.....I am in the process of rebuilding my complete brake system on a  '49 B1B.  I purchased new wheel cylinders from AB.  I just checked the old double ended wheel cylinder I took off and there are two holes,  one that goes straight in from the hose port and one that goes in straight in from the bleed port. So there are clearly two holes, the one from the hose port intersects the cylinder bore at the bottom and the one from the bleed fitting intersects the cylinder bore at the top.  If you are certain you have only one hole intersecting the cylinder at the cylinder I would say you have the wrong one for this application.  I would be tempted to run a thin wire through the hole of the bleed port to determine how it intersects the cylinder bore or the single hole of the hose port.  Maybe the bleed port hole was missed and not drilled during manufacture. 

[desoto1939]

This is rich Hartung with the 39 Desoto and I have the step down wheel cylinders just like you have on your 41 Chrysler.  There is only 1 hole in the middle of the wheel cylinder and it is in the same location as to what you have shown in the picture of your wheel cylinder. so that is not the problem.

 

You have stated that when bleeding the brakes you no longer get any air bubbles in the collection jar. So that indicates that you have bleed the system of air. If you have done this with all four brakes.  The go back to the right rear drum and bleed this line only. Let us know if you get any air bubbles. If not, then you have an adjustment problem of the shoes to the drum. With no air bubbles then the system is free of air.

I still feel that you need to use either the Ammco 1750 brake gage or the factory miller brake setting tool to get the proper setup for the shoes to not feel soft.  The softness is due to the shoes not being adjusted correctly.  I do have the Ammco brake tool.  If you have an old time mechanic then I would have them involved with the adjustment. Some of the new young guys do not understand the older systems

Rich Hartung   Desoto1939@aol.com  cell 484-431-8157  home 610-630-9188  call me

[dale]

I put new brake cylinders on front and back along with new shoes, master cyl,  and hoses on my 46 Plymouth.  Must have bled system a dozen times according to correct procedure and adjusted the shoes several times to get correct clearance and still very soft petal.   Gave up and put disc brakes on front. and used the stock master cylinder...  Bled front calipers one time and the petal is rock solid.  The petal was actually hard before I even bled them.   In my opinion stock drum brake systems on these Chrysler cars suck.

[squirebill]

Wow.....help me understand this: If there is only one hole going from the wheel cylinder bore (at the 3 o'clock position in the photo of post #1 of this topic) to the hose port and the bleed port on the back of the wheel cylinder, as 1949 Goat infers, how do you get the air out of the part of the cylinder that is above the inlet port once the fluid level comes up above the port?

[Dodgeb4ya]

9 hours ago, dale said:

I put new brake cylinders on front and back along with new shoes, master cyl,  and hoses on my 46 Plymouth.  Must have bled system a dozen times according to correct procedure and adjusted the shoes several times to get correct clearance and still very soft petal.   Gave up and put disc brakes on front. and used the stock master cylinder...  Bled front calipers one time and the petal is rock solid.  The petal was actually hard before I even bled them.   In my opinion stock drum brake systems on these Chrysler cars suck.

Do the stock brakes right and they work right.

[ptwothree]

On 10/17/2016 at 1:56 PM, 1949 Goat said:

On my 1941 Chrysler C28 with the Lockheed series 1 brakes I am having issues with proper bleeding

I rebuilt the front brake wheel cylinders and replaced the flex hoses and shoes.  The new shoe brake material is thinner than the old shoes by .05 of an inch, but it does cover the entire shoe on both sides compared to the old shoe that only had 2/3 coverage on the trailing shoe.

I have none of the measuring tools to set the brakes. I did cut a slot on the anchor pins, so I can adjust them when the hub is on. I adjust the lower anchor pin cams to get slight brake drag then adjust the upper cams to get slight drag again. I did this on both front brakes, master cylinder pumps good, using DOT 3 fluid.

I have bled the brakes and tried adjusting the cams to improve brake pedal firmness. The on first brake application the brake pedal is soft and travels near to the floor, a couple of pumps and the braking and pedal travel is acceptable.

You can see in the photo that the fluid hole is half way down the cylinder. I am thinking that there must be some air being trapped at the top of the cylinder when I am trying to bleed?

I was thinking about putting a side of the car in a ditch to get the hole near the top. Hopefully some other easier tips.

Thanks for you help.

Did you remember to install the copper sealing washers?  Two for the fronts and one for the rear hose.  It happens.....

[1949 Wraith]

Yes, I did replace the copper washers. The system is sealed and does not leak, it does maintain pressure.

I replaced the new thin AB shoes and put on the old worn thicker shoes and I have an improvement in pedal firmness. I will try adjusting brake shoe position to get further improvement.

15 hours ago, squirebill said:

Wow.....help me understand this: If there is only one hole going from the wheel cylinder bore (at the 3 o'clock position in the photo of post #1 of this topic) to the hose port and the bleed port on the back of the wheel cylinder, as 1949 Goat infers, how do you get the air out of the part of the cylinder that is above the inlet port once the fluid level comes up above the port?

This is why I thought of putting side of car lower to move the position of the port from 3 o'clock closer to 1 o'clock to aid in bleeding off any trapped air .I have had some older motorcycle calipers where I had to remove and re position them so the bleed was at top position.

[desoto1939]

The single hole in the wheel cylinder is not an issue.  These stepdown cylinders were used for many years on the chrylser products. I have them on my 39 Desoto.  Since 1949 Goat has stated that there is no more air bubbles when he bleeds the brake then it is an adjustment issue.  The drums might have been cut a couple of times and they might have been overcut. Another suggestion is to take the drums to a repair shop and have them officially micrometer the diameter of the drum opening. If they have been over cut them there is not enough  thickness on the drum and they should be replaced.  If at the max then the brake lining would need to be shimmed with the proper thickness behind the lining and against the metal brake shoe.  This is what was done in the old days when they used riveted linings and the drum was cut to the max.  I still fell that it is a brake adjustment issue because when he pumps the brake pedal he gets a hard pedal so that is meaning that the shoes are moving outward but they are to far inward and the second push moves them out more then the first push. As I have suggested he needs to get the Ammco brake gage to officially adjust the shoes and to eliminate the adjustment issue. Then if a problem we can at least make more suggestions. I told goat 49 that I have the Ammco tool.

Rich HArtung

Desoto1939

 

[squirebill]

1949 Goat,  I'm with you.  I don't understand how you can get a complete air bleed from the wheel cylinder with only one hole at the 3 o'clock position of the wheel cylinder.  My brake cylinders have two holes in them  at 6 & 12 o'clock.  If I had cylinders like yours I would bleed them as follows:  Remove drum and shoes.  Place "C" clamp across the wheel cylinder to prevent the internal spring from pushing the pistons out of the bore.  The large rubber end caps on the cylinder usually prevent this but I use the c clamp as insurance.  With the brake hose still attached to the cylinder unbolt the cylinder from the backing plate. Pull the slack out of the brake hose and orient the cylinder so the brake bleed fitting is facing up.  I attach a clear poly hose to the bleed fitting arching it up then down into a container.  Crack the bleed fitting open and wait for the fluid to start filling the poly tube.  It may take a minute or two but the head pressure from the fluid in the reservoir will slowly fill the cylinder pushing the air out. You may see air bubbles coming into the poly hose.  When the bubbles stop and it is just fluid filling the poly tube, close the bleed fitting.  Reassemble everything.  Turn all adjustments back so drum spins freely then adjust each adjustment out so it just locks drum then back it off a bit to a free spin.  Go to next adjustment and do the same.  Oh, while the drum and shoes are off, check the fit of the shoe to the drum.  Sand the shoe for a fit you are happy with.  Personally, I have never done this shoe fitting but it seems highly recommended by others on this forum.  Regards. 

[Don Coatney]

37 minutes ago, squirebill said:

1949 Goat,    It may take a minute or two but the head pressure from the fluid in the reservoir will slowly fill the cylinder pushing the air out.

That may work on vehicles  with the brake master cylinder located on the firewall above the wheel cylinders. But with the master cylinder located below the wheel cylinders that will not work.

 

If the pedal is spongy and must be pumped up to get firm there is air in the system and needs more bleeding. If the pedal stays firm on the first pump but goes too far down then it is an adjustment problem. There are strong return springs on the brake shoes and they return home with every pump. They do not go half way on the first pump and all the way on the second pump.

[1949 Wraith]

15 minutes ago, squirebill said:

1949 Goat,  I'm with you.  I don't understand how you can get a complete air bleed from the wheel cylinder with only one hole at the 3 o'clock position of the wheel cylinder.  My brake cylinders have two holes in them  at 6 & 12 o'clock.  If I had cylinders like yours I would bleed them as follows:  Remove drum and shoes.  Place "C" clamp across the wheel cylinder to prevent the internal spring from pushing the pistons out of the bore.  The large rubber end caps on the cylinder usually prevent this but I use the c clamp as insurance.  With the brake hose still attached to the cylinder unbolt the cylinder from the backing plate. Pull the slack out of the brake hose and orient the cylinder so the brake bleed fitting is facing up.  I attach a clear poly hose to the bleed fitting arching it up then down into a container.  Crack the bleed fitting open and wait for the fluid to start filling the poly tube.  It may take a minute or two but the head pressure from the fluid in the reservoir will slowly fill the cylinder pushing the air out. You may see air bubbles coming into the poly hose.  When the bubbles stop and it is just fluid filling the poly tube, close the bleed fitting.  Reassemble everything.  Turn all adjustments back so drum spins freely then adjust each adjustment out so it just locks drum then back it off a bit to a free spin.  Go to next adjustment and do the same.  Oh, while the drum and shoes are off, check the fit of the shoe to the drum.  Sand the shoe for a fit you are happy with.  Personally, I have never done this shoe fitting but it seems highly recommended by others on this forum.  Regards. 

Bill if needed I had been thinking of doing something along that line. Getting a bit sick of messing with these brakes.

Yesterday I made some aluminum spacers and placed them inside the pistons where the shoes contact. I figure this should shorten the internal stroke and compensate for any hub wear. Hubs look pretty good at about 1/4 inch thick. I am reusing my old brake shoes since they are considerably thicker than the new ones I got from Andy Bernbaum and they should be basically shaped for the hub.

I will see if normal bleeding procedure gets me anywhere today.

[1949 Wraith]

5 minutes ago, Don Coatney said:

That may work on vehicles  with the brake master cylinder located on the firewall above the wheel cylinders. But with the master cylinder located below the wheel cylinders that will not work.

 

If the pedal is spongy and must be pumped up to get firm there is air in the system and needs more bleeding. If the pedal stays firm on the first pump but goes too far down then it is an adjustment problem. There are strong return springs on the brake shoes and they return home with every pump. They do not go half way on the first pump and all the way on the second pump.

I think with a clamp on the pistons, bleeder hose filled with fluid and hose end submerged into fluid.

Open bleeder and very gently apply pressure to brake pedal should expel any air.

[squirebill]

That'll work too.  I'm working with a B1B on jack stands and quite frankly it is a pain in the butt to get up and in it.  For the left front wheel I can reach in and apply the brake pedal by pulling / pushing it away from the floor board from under the hood.  Of course to be able to hold the cylinder so the bleed fitting  faces up, I find kneeling and waiting just seems to be easier.  The big deal here would be to get all the air out so holding the cylinder in your hand and tipping it from end to end as the fluid is filling it is what's important.  You guys are working with cars.  Is the master cylinder lower than the wheel cylinders? 

[1949 Wraith]

Master is under the drivers floorboard but the brake lines run higher than the reservoir up around the suspension etc.

If I get to this stage I think it would work better as a 2 person job.

 

[desoto1939]

OK. So I have the same setup as goat of his Chrysler. My master cylinder is located on the frame rail under the floor board so we both have the same setup with the master cylinder and also the same individual wheel cylinders that are also know as stepdown cylinder because of the two different size inner pistons.

So I have been driving my car for the past 30 years yea 30 years and the car still has the original wheel cylinders and master cylinder.  So may car is 76 years old and have a good braking pedal. I did have a soft pedal once and that was due to the adjustment issue of the shoes.  I have recommended that Mr Goat go and have his individual drums measured with a good micrometer such as an Ammco tool this will cost him some money but this will at least tell him if the drum have been over cut or not.  This then eliminates one issue or might be the issue.

Then I have told him that I have the AMMCO Brake gage tool 1750 to adjust the brakes, this tool was used by the dealers and also mechanics to adjust the brakes to the proper setting.  He has not taken me up on the offer of the tool.  So I do not know what else we can do for him  He has the stock system.  He has also stated that there are no air bubbles when he bleeds the brake so that indicates that there is no issue with air in the system because if he continues to bleed the brakes as he is stating then the air has been removed.

So the next part is on him to get the drum miced and measured.  If they are over sized I have also suggested that he get a set of brakes shoes that are riveted style but will need to have shims of the proper thickness placed behind the shoe lining to take up the extra space because the drum are oversized. also will need the correct sized rivet.  Then will still need the use of the Ammco brake gage to get the shoes set to the proper arc.  The brake shoe lining number that is the stock lining is an 1162 number this is a number that is used by all lining manufacturers so is generic across the board.  I also do have some extra riveted lining if he needs them.

 

Also to the bleed the brakes in the traditional manner this is a 2 person job. One in the car and one under the car at the individual wheel cylinder and they have to work in tandem to do the job correctly.

Rich Hartung

Desoto1939@aol.com

cell 484-431-8157

 

 

 

[1949 Wraith]

OK, so now I am convert to the brake shoe adjustment.

I had been only working on the front brakes of this car. I had only bled the rear brakes to make sure the system was flushed with new brake fluid.

Adding the spacers did aid in shortening the piston stroke in the front wheel cylinders and improve pedal height, but it still was not as good as it was before I rebuilt the front cylinders. I decided to bleed the rears again, no change.

I jacked the rear end and checked the drag on the shoes the left had slight drag but the right turned free. I adjusted the minor adjuster so there was a slight drag on both shoes and they were very slight adjustments.

After that adjustment my brake pedal is back to the way it was before I started working on the brakes. 

So if anyone is working on front or back brakes and they are having pedal travel issues. Check the adjustments on the brakes that you did not touch.

PS; I have a rear hub puller now, to get at the back brake rebuild. If the car stop good I will just drive it until the season is over and work on it then, for now a nice change I will              rebuild the Bendix brakes on my Chev 1/2 ton

 

 

[Dodgeb4ya]

He must also arc the shoes to each drum or wear them in first ( this could take years if he doesn't drive the car much ) before any shoe adjustments so there is 100% lining contact with the drum.

This causes a high firm pedal and good stopping power although with new Chinese linings no guarantee anymore!

[desoto1939]

On the latest picture of the brake shoes that were on the car I noticed that the front and bottom part of the lining was not chamfered but had a blunt end to them. These shoes should have been cut at an angle to help with the roatation all of my lining have the  slight angle cut so you have a smooth transition into the braking shoe material.

 

Rich hartung

[1949 Wraith]

I would like to correct any mis-information I might have caused about bleeding Chrysler wheel cylinders.

Working on my rear brakes today you can see on the smaller cylinders show the 12 o'clock bleed port cast in the body. This port was not evident in the larger and thicker cast front wheel cylinders.