Outer Limits 4x4 Board

Hi guys. We have just upgraded the brakes on my friends 80 series, as the pedal was just sinking to the floor. Replaced master cylinder, rear drum cylinders, replaced front calipers and rotors for 100 series units, removed and bypassed that stupid proportioning valve which was siezed, and bled like crazy. Gone through 10 bottles of fluid. We've tried everything and to no avail. Whats the go??? Has anyone else had this problem. You can get brakes if you pump up the pedal, but it just sinks back down a few seconds later. Please help.

was all replacement parts new ?

did u bleed the left rear 1st

right rear 2nd

front left 3rd

front right last ?


are all the connections tight no leaks ?

did u adjust the rear shoes before bleeding ?

It is so hard to get the air out of the master and pipework from it.... start by taking both hoses off it and hold fingers over the ports, then pump....when all air is gone, reconnect pipes and break pipes at next joint....then the next...

Booster might be rooted.

yep did all that. ended up clamping off all the hoses and got a solid pedal. took off one clamp at a time and found that the problem is in the front pipes on the diff after the rubber hose. can you get air stuck in there anywhere?? or is it likely to be a caliper?

if there is no leaks it sounds like air

get some clear washer bottle hose connect it to the bleed nipple and fit the other end into the brake resivoir
crack nipple and pump away , have someone watch the clear hose and check for any air bubbles .

even get enough length so u can also do the rears as well and know its definitly out of air

thanks for the tip. we'll give it a try on the weekend. need to get out and do some wheeling asap.

I would just take it to a brake place. It'll do your head in trying to get it out. They'll pressure bleed from the master cyclinder. It was the best thing i did I have the best brakes, high hard pedal. I tried and tried to get the air out to no avail.