Rear brakes dragging (1 Viewer)

[MaltbyPenn]

I have a 76 resomod with a SBC and hydroboost brakes. I've been trying to tune the sniper so I haven't driven it since the rebuilt other than in and out of the garage.

Pulling it out of the garage, I felt the brakes pretty heavily on. I have a new 1" willwood master cylinder, stock disc's up front and Monte Carlo conversion in the rear.

When I loosen the master cylinder off the hydro boost, the brakes release. I installed a couple washers to space the MC off the booster and the brake unlocked and seemed to work.

I machined down the "bullet" spacer inside the MC that the booster pushes on the thickness of the washers. The brakes seemed to work and release.

I've ensured the brake petal is loose and not applying pressure on the booster.

Today I ran the engine "tuning" for about 20 mins. After that, brakes were locked up again. I've remade most of the brake lines so I'm sure I dont have a residual valve inline. I also have a proportional valve off the MC but it's not adjusted. Other than a couple elbows or connections that I haven't replaced, which theoretically could have crap in there, the whole system is pretty much new.

Any thoughts on why my brakes keep locking up?

 

[aljollano]

Did you measure the length of the booster pushrod the proper way/tool?

A J

 

[MaltbyPenn]

Did you measure the length of the booster pushrod the proper way/tool?

A J

Yeah, I used this tool: JEGS 631315: Master Cylinder Push-Rod Length Gauge - JEGS High Performance - https://www.jegs.com/i/JEGS/555/631315/10002/-1?gclid=Cj0KCQiAk4aOBhCTARIsAFWFP9EE9GwD5HNwyoCl6uSBuiVTup7MFxNzeGwsdKpqaXYp9_qX6z8GxYwaApO4EALw_wcB#

I appreciate the question and fortunately, I've found my problem. I was under the rig looking at elbows and fittings and noticed my estopp electric parking brake was half engaged. I had an under sized fuse and it blew at half pull. This also disabled the brake warning light on my dakota digital. So much for all the high tech