BRAKE BLEEDING UGH

[golddigger]

hello there  I am having problems bleeding brakes on my 88 MJ

replaced front calipers and mc  BLED 5 TIMES REAR TO FRONT  STILL SOFT PEDAL TILL LAST BIT OF PEDAL

any help would be welcome

I have done brakes hundreds of times before,  what am i missing 

 

John  

[watchamakalit]

There is a special bleeding methid for comanches due to the load sensing valve in the rear. 

[GonzoTheGreat]

 

 

 

[ratrapp]

my load sensing valve was bad and i never could get a good pedal until i bypassed the valve.also make sure your caliper bleeder screws are on top or youll never get a pedal.

[golddigger]

Thank  you all for the input,

I have followed this procedure.

on steps 9, 10, 11 it never came to be for me  I did bench bleed the MC as normally a person would let it drip then started bleeding 15 seconds between compressions till clear fluid 

perhaps the little piston  never shuttled as called out in the FSM in the front valve, the brake indicator light is working as it should when park brake is applied.

 

this is why i reached out.

Ill need to find something softer to bang my head on it is starting to hurt now.

 

John

 

[golddigger]

WELL 2 weeks later a gallon of brake fluid new master new front calipers 

no air in front lines 

no air in rear lines 

no efffn brake pedal still  only at the very end of the compression is there enough to get the truck to half @$$ stop     

come on man I have done hundreds of brake jobs  this one is beating me up   

 I tried the open the right front bleeder method  could not get light to come on with the key on ( light does work  circuit is good)

 

what else this bleeding  is bleeding me 

any help would be great 

thank you  

John

 

[ratrapp]

how tight are your rear shoes?if the adjustment is backed off too much you'll have a low pedal.once again i had to delete my load sensing valve to get a pedal on my mj.i had plenty of fluid flow to the wheels but no pedal.there is a possibbilty you have a bad brake booster.

[golddigger]

13 hours ago, ratrapp said:

how tight are your rear shoes?if the adjustment is backed off too much you'll have a low pedal.once again i had to delete my load sensing valve to get a pedal on my mj.i had plenty of fluid flow to the wheels but no pedal.there is a possibbilty you have a bad brake booster.

I already changed the booster and the master   rear brakes are adjusted perfect  slight drag  

it seems like the pedal ends traveling before the brakes can get full pressure there is no air in  the lines 

 

John

 

[llhat]

was the 'height' of the pushrod checked with the new master cylinder and booster?

If too short, full travel maybe not there, if too long, not enough stroke... 

 

 

[ratrapp]

how did this happen?did you lose brakes suddenly or were you replacing parts and then lost your pedal?

[golddigger]

Good Morning,  thank you all for chiming in 

I have the problem corrected  now    it was the new booster pushrod length I assumed it was correct out of the box      NOPE   I was able to pull the master away from the booster far enough make the adjustment without breaking the lines loose    because a one man bleeding team is no fun,

after a few tries  i was able to get my pedal back    Yaaaay     I have the booster depth tool coming today and will be able to make the proper adjustment   

 

again thank you for all your assistance 

 

John

13 hours ago, llhat said:

was the 'height' of the pushrod checked with the new master cylinder and booster?

If too short, full travel maybe not there, if too long, not enough stroke... 

 

 

 

[golddigger]

Just now, golddigger said:

Good Morning,  thank you all for chiming in 

I have the problem corrected  now    it was the new booster pushrod length I assumed it was correct out of the box      NOPE   I was able to pull the master away from the booster far enough make the adjustment without breaking the lines loose    because a one man bleeding team is no fun,

after a few tries  i was able to get my pedal back    Yaaaay     I have the booster depth tool coming today and will be able to make the proper adjustment   

 

again thank you for all your assistance 

 

John

 

that was the issue   

thank you for the input