Great Lakes 4x4. The largest offroad forum in the Midwest - View Single Post - Hydroboost brakes- no pressure to rear?
View Single Post
Old November 29th, 2006, 12:28 PM   #1
Senior Member
Strangler's Avatar
Join Date: 12-12-05
Location: Howell
Posts: 4,843
iTrader: (53)
Mentioned: 40 Post(s)
Default Hydroboost brakes- no pressure to rear?

I converted my FF 14 bolts brakes to disc, using 78 K25 calipers and rotors on my 97 K2500. When I did this (4 months ago), I threaded the stock rear brake line into a small adapter (to change thread) and then into the caliper.

I bled the brakes like any other vehicle... pump, pump, pump. hold, bleed.

I then did the front when I put the Dana 60 under it. Changed the brake lines (to longer ones), filled the m/c and pump pump pump , bleed.

Brakes worked great! They were a little strong in the rear with the disc, but they worked great for 4 months. I then developed a squeal in the rear, which was caused by gear lube leaking from the hub seal, onto the rotor.

I dissasembled the axle, brakes and hub to repair.

Upon re-assembly I cracked the stock hardline when the caliper slipped out of my hand, so I ran to the parts store, bought some line and replaced the lines from the rear axle "T" to the calipers.

The M/C never ran completely dry.

I filled the m/c, and proceeded to pump and bleed as usual...... nothing.

I now have very little pressure at all. I disconnected the lines at the "T" and checked again.... with someone hitting the brake I still have very little pressure thru the line. I reassembles the lines and gravity bleed everything, then used a mity-vac, then tried bleeding as usual, and I still have no pressure- the pistons arent even moving in the calipers.

The pedal blows right thru the first half of its stroke, and is SSLLOOOOWWWW to return.

Any ideas? What did I do wrong? How do the proportioning valves work- could it be "stuck" and not allowing pressure to the rear?

When my assistant has the brakes pumped up, and I crack the bleeders, fluid just peeters out, instead of spraying whether the engine is running or not.

Ideas? Bueller? Bueller?
Strangler is offline   Reply With Quote
Page generated in 0.31163 seconds with 22 queries