Thread: Bleeding master cylinder? Any tips / best practices?

Hello All,

Since swapping in my new motor and converting to non abs I have not found anything on bleeding the master cylinder. I read about bench bleeding etc but my stuff is all installed on the car.

My one friend said I can just open up all the bleeders and let it gravity bleed. And then once I have fluid coming out of all 4 bleeders I can close them all up and proceed to do a the standerd bleeding.

Is this correct for our cars?

Doing it this way the front calipers both starting spitting bubbles and eventually just fluid but the rears aren't really doing anything.

Any advices would be great I hope I dont have to bench bleed as the master cylinder has fluid in it and was a paint to setup dont wanna get brake fluid on my newly painted engine bay.

Thanks in advance,

problem with bleeding is that the MC sucks air back in when you release the pressure. so either keep your fingers over the

do it the right way. get the bleeder plastic attachments from NAPA or an auto store. there's 4 of em, so you'll probably need to buy 2 sets. use the hoses to dump into the resevoir and suck in fluid on release. if it's still on the car, you probably will need help to keep the hoses in the resevoir. other option is to use your fingers to cap off the holes while pumping, but you will need help. then install the hard lines.

Rule of thumb when bleeding brakes. Start at the furthest brake caliper from the master cylinder and work your way to the closest. So in our case, right-rear, left-rear, right-front, left-front. One at a time. If you dont have any of the bleeding equipment and tools and stuff just do it the old fashioned way of pumping the brakes, hold, open bleeder. I like to give it about 10 pumps, hold to the floor, open the bleeder to let the air escape, close, then let of the brake. Must hold brake down to the floor, once the pedal gets stiffer. You need to let it travel to the floor without letting it move back upwards at all or it will suck air back in. Do it to all 4 in the order i described and be done with it.

A lot of shops have machines that hook up to the master cylinder in place of the cap and actually applies a small air pressure to the brake fluid then they just go around one by one and open the bleeders until a steady stream of fluid comes out. Again working from furthest from the MC to the closest. Top off reservoir and done.

When your doing the pumping procedure you tend to go through more fluid so just make sure the fluid level in the reservoir is not to the point where air will get in and then have to start all over. Basicly do one caliper at a time and top off reservoir.

Thanks guys, I know how to bleed the brakes for the most part its just the master cylinder that concerns me since I swapped from non-ABS.

I have a friend who says he knows a way using a special vacuum or something ill keep everyone posted. Maybe it can help others out.

I was a total noob when I installed my Altima MC. I put it on the car dry, filled it with fluid and bled the brakes as normal. Worked out supremely. Never even thought about doing it differently. I guess I got lucky...

Dude I thought the same, No clue you had to bleed the M/C ( NEWB AS well )

Hopefully everything goes good I can almost taste boost, Now that 3" exhaust kicked my ass with the Kart Boy hangers OMG it like feels like its bolted to the chassis its so stiff was hard to align but now doesnt budge.

Going to have to make a new center/cat bracket though hacked the stock to work for now.

When I installed my altima master cyl, and max rear brakes I put a hose on the master cyl lines and blew them all out dry. I did that to get all of the old fluid out. It was real nasty looking. Probably never done before. I ran a good bit of fresh fluid through it in the cleaning process. I upgraded my fluid to DOT4 since it lasts longer. The DOT3 is said to be good for 1 year, while DOT4 lasts 3 years. This is all based on the rate it absorbs moisture from the air. I don't know of anyone who gets a brake fluid change, or any other fluid change besides oil. Hell some ppl skip that, and then get pissed when their car brakes down, lol. It's that good old routine maintenance.

This thread is about bleeding the MASTER CYLINDER, not the brakes....

I personally bench bleed them before installation. They sell kits that are plastic fittings with plastic tubes that you run off the brake line fittings and into the MC itself. Fill it with fluid and pump away. This is THE BEST way to do it on or off the car. If you buy a new MC they typically give you the kit....

Thanks Wes, I believe this is kinda what my buddy is talking about something about lines and a mighty vac he was saying. Ill keep everyone posted. Just wanna get everything done right the first time.

Thanks again

^^Well, if you have everything installed already, and you bleed the calipers, you are effectively bleeding the master cyl as well. Since that's the fluid's origin point. I just put that anti-squeel spray on my pad backs, and rebled my entire system last weekend. I went by home depot and picked up a roll of that clear poly tubing to attach to the bleeders. It was 1/4" I.D. x 20' for less that $5.00 I just run that into an empty oil bottle for disposal, and so I don't make a big mess. If you had some one man bleeder screws, or a one man bleeder pump then its pretty easy. If you don't it will require 2 ppl. I always use some of that clear poly hose no matter what though, it helps alot.