i had a brake line burst on me the other day, thankfully while i was in my driveway, and decided to replace all the lines. i got my new lines in and there are no leaks in the system that i can find. i bled from all four calipers twice and im not getting air from the calipers anymore. when i start it up the pedal goes the whole way to the floor. how do i know what the problem is and how do i fix it. its a 97 bravada awd abs. thanks

 

You did not happen to suck air into the master cylinder did you? If so, then you have to bleed the master cyilnder first, then move to the wheels. Bleeding the master cylinder can be challenging sometimes.

 

i paid very close attention that the fluid didnt run low. is it possible air got in the mc when the line blew? the break was only 2 or 3 feet from the mc

 

It depends on how many times you pumped the brakes after the line blew. Was the reservoir empty when you started working on it?

It is possible that air sucked back in through the broken line...

 

no it wasnt. but i did pump them a couple times after it blew. im guessing i sucked air in through the busted line. also i can here a strange noise coming from the reservoir when releasing the pedal sounds like the gasket is sucking air, could that cause problems?

any tips on bleeding the mc in the car?

 

You need to disconnect the lines, then put some other lines on that you can direct back into the reservoir below the fluid line.

You can tell when there is air in the master cylinder by watching the fluid in the reservoir as you apply the brakes. If it shoots back up in the res, then there is air in the cylinder.

 

what size fittings are on the mc? 9/16-18 for the front and 1/2-20 for the rear ? also if there is air in the abs unit how do i bleed that

 

The ABS unit should bleed out during normal bleeding procedures. The older units required a special procedure using a Tech1 scan tool, but the newer ones used in the 2nd gens should not.

 

i havent been able to look at my car in the past few days but i bled the mc and bled each wheel 3 times after that. the pedal feels normal when braking normal but if i slam the brakes the pedal goes almost to the floor, it seems to stop good but i dont want to drive it like this. any ideas or should i just flush another bottle of fluid through the system

 

This can be a very tedious process... you just gotta keep bleeding the air out. If you get to your wits end then maybe find a shop with a vacuum bleeder. Shouldn't charge you too much to bleed them out.