Daronw

Calipers are on the correct side and I did bench bleed the master cylinder. I’m pretty sure it’s the line to the load leveling valve. Thanks for the help!

Here’s my 1986 MJ 4x4. I swapped in a 3.4l stroker v6. It’s got Holley sniper fuel injection, edelbrock 4 barrel intake and headers, MSD 6AL ignition. A fiberglass cowl induction hood, 2” lift with 31’s. I’m the third owner and had it for 25 years.

The truck had been sitting for many years but when it was put away the brakes were fine. I decided to change all the parts because of it sitting. Ran out of time today to try that bleed procedure. Hope to get it tomorrow.

Thanks I’ll look for it.

I’ve got an 86 MJ and I’m having a really tough time with the brakes. I’ve replaced both rear wheel cylinders, both front calipers, master cylinder, all three rubber lines, rear steel lines on the axle and the left front steel line. I’ve looked at all the other lines and none appear to be leaking. The wheel cylinders, calipers and master cylinder show no signs of leaking. I’ve bled and bled. I get a firm pedal but as soon as I start the truck the pedal goes to the floor. I disconnected the booster vacuum hose and the pedal stays stiff but there is very little braking action. I put a vacuum pump on the booster and pumped it up to about 10 pounds of vacuum. The pressure held for over an hour until I released it. The booster and check valve don’t appear to be the issue. What am I missing here? Could it be the proportioning valve below the master cylinder or the load sensing valve by the rear axle? I’m scratching my head as I’m running out of things to try.