Need Help PLEASE
 

i have a 1988 Dodge Dakota have tried everything i can think of , i broke a rear brake line after replacing it cant get brakes to build up put 2 master cylinders on , changed power booster ,cleaned n adjusted rear brakes , cleaned n checked front brakes , i have tried resetting proportional valve still no luck PLEASE HELP

Welcome to TF

I'm assuming the brakes were bled & in the correct order after the line was replaced? Get a helper & start Bleeding the air out @ the passenger rear , then the drivers rear , then passenger front & the drivers front last. Sounds like air in the system.

Exactly, there must be air in the system. You should blow the air out.