Help! Bled the air assist slave brake cylinder Instant no brakes

[Torisco]

Bled the air assist slave brake cylinder Instant no brakes

I changed the front axle boots and had to remove the two brake lines from the wheel cylinders.

During the boot replacement I inspected all brake components, then adjusted the brakes and bled the two wheel cylinders on the front of the truck.

Everything was fine. Good brake pedal. Then I kicked myself for not bleeding the slave brake cylinder attached to the air assist cylinder FIRST (as instructed to in the TM bleeding procedure)

So I bled the slave cylinder and immediately lost the brake pedal all the way to the floor.

Re bled the slave cylinder and the front two wheel cylinders and still have a brake pedal to the floor.

The troubleshooting section of the TM shows that it can be the air assist cylinder, the master cylinder or the slave cylinder. Before getting deeper nto trouble, can anyone give me a clue on what to do next.

Any suggestion will be greatly appreciated

 

[Srjeeper]

First you need to remember this is a single circuit system. There's no front or back like in a car....it's all one system. So follow the TM...start bleeding at the MC, then air pack, back to right rear, left rear, right front rear, left front rear, right front steering, then end at the left front steering.

You need to bleed the entire system from the farthest wheel ending at the closest wheel.

If your doing this by pumping the pedal, expect to do this several times before you have the correct brake pedal.

If your using a power bleeder, you should still go around everything in the proper sequence more than once.

Good luck....

 

[Heavysteven]

Dito

You need a power bleeder

M35A2 Power Bleeder 2 of 2 - YouTube

 

[Katahdin]

If you had first clamped the hose going from the frame to the front axle before removing the lines, then you might have gotten away with just bleeding the airpack and front wheel cylinders.

 

[Kaiserjeeps]

The duece power bleeder is the cats meow. I just made a duplicate DOT 3 bleeder with a aluminum block master cylinder cover for civi applications. I was so impressed with the first bleeder I had to make another for dot 3 fluid.

The duece power bleeder is definately worth the time to make. The return is huge.

 

[joshs1ofakindxj]

If you had first clamped the hose going from the frame to the front axle before removing the lines, then you might have gotten away with just bleeding the airpack and front wheel cylinders.

Clamping a house risks damaging it.

Pressure bleeders are the way to go. Spend $20 or less and whip one up.

 

[Torisco]

Makin a pressure bleeder

Well, a great big thanks for the replies so far.

It seems that I should pressure bleed the system thoroughly and then see if the problem remains.

I am going to look at threads for doing this. At $20-25.00 cash investment I cannot go wrong.

Will let you know what happens, Ordered one gallon of mil spec silicone brake fluid and have to wait for it to arrive.

 

[Srjeeper]

Couple tips..

When you do get your bleeder and get it hooked up, there's some things to remember.

You don't need more than 20psi. in the bleeder to do the bleeding properly.

Always use a small hose in a clear plastic bottle from the wheel cylinder, to see what and how much air and other junk comes out each wheel.

When you have the bleeder hooked up and pressurized 'Do Not' touch the brake pedal till you've gone completely around the truck. Then remove the bleeder before trying the pedal.

I do my truck every spring and bleed each wheel cylinder till I get fresh fluid coming out. You'd be amazed at the rust particles that come out each year. This is the 7th. year on this truck and I've yet to have any issues..."Touch Wood"..!!!

Also you don't need to have the truck running or have a full load of air to 'test the pedal'....if it's bleed and the shoes are adjusted properly, you'll have a good pedal right away.

The real beauty of a power bleeder is ya don't need Soldier B, the Wife, Girlfriend, Neighbor, Kid, Mother, Father, Sister, Brother or Homeless Guy down the street looking for some $ for a bottle, to get this job done. As is usually the case, it's some much nicer to be able to do a job, on your truck, by yourself with out all the other crap that always goes along with a helper.....and that list is endless!!

 

[Floridianson]

Sorry your haveing trouble but why did you disconnect the lines? If you replaced the slaves I see but if not I just hang the whole backing plate with wire on the frame of the truck when serviceing nothing but the boots/ seals.

 

[Torisco]

Sorry your haveing trouble but why did you disconnect the lines? If you replaced the slaves I see but if not I just hang the whole backing plate with wire on the frame of the truck when serviceing nothing but the boots/ seals.

I thought of doing that...but the length of the brake line hose and knuckle housing removal intimidated me , as well as the TM instructions to disconnect the brake line.

I knew I would have to bleed the system but was not prepared to have the pedal go imediately to the floor and then stay that way after bleeding the air pack cylinder and both front wheel cylinders...Oh Well?

 

[Torisco]

Thanks to all who helped me in this matter. I made a homemade pressure bleeder and bled all the l;ines from the farthest to the nearest after doing the slave cylinder FIRST.

Got my pedal back and am now adjusting the brake shoe clearance for all six drums.

THANKS AGAIN!

 

[BigEMobileTech]

This is a reply to my original post i believe i put in the wrong section, someone had asked where the MC was vented. It is vented ight at the resevoir plug with a standard breather. I have been thinking about it and the next thing i want to do is adjust all brakes before continuing. The vehicle is in the middle of a field on a farm or I would have removed all wheels and hubs by now to check each wheel cylinder. If using the 2 soldier method to bleed the brakes should i disable the booster when doing so? I do plan to make a pressure bleeder of my own but for the time being i want isolate the issue because i have bled the lines several times as well as the air pack in proper sequence as well. I purchased some plugs and unions to use to block off sections of brake line at various locations but since i am not losing any fluid anymore i am really confused as to why i cant get any pedal.