Dan H.

I have my car up on jacks to perform a bunch of wintertime maintenance and upgrades. I have it mostly back together in preparation for my first track day in a few weeks. I changed my brakes over to my track rotors and pads which require compressing all my calipers to put everything together.

I need to do a bleed, my question is can I bleed the system when all the calipers are compressed? Or do I need to start up the car and pump everything up before bleeding which will requires that I put it on the ground and jack it back up.

Thank you

ErnieN85

yes you can . no particular problem with that as long as everything is together

dbratten

I always start with a firm pedal. I usually have the four wheels off the car as it is so much easier to get to the calipers to do the bleed. I just reach in and pump the foot pedal with my hand until I can't move it. This fills all the calipers and transfers fluid out of the master cylinder which you can then fill prior to bleeding.

I'm not saying the other method doesn't work, only that I haven't tried it.

--Dan

UstaB-GS549

I just pump the brakes with the engine off to push the pistons back out after a pad change and then start bleeding.

craig-o

What technique are you planning to use? If you are doing this as a 2-person job, where one person is pushing on the pedal while the other opens the bleeder valve, the first few pushes will likely push out the pistons before the bleeder is opened.

If you use a pressure bleeder (like one from Motive), when you pressurize the master, the pistons will be pushed out.

If you use a vacuum bleeder, the position of the pistons may not change.

But what's the concern? In none of these cases will you need to start the car to pressurize the system; only push the pedal. Just leave it up on jack stands and bleed the system.

In any case, to be sure you fill the master cylinder reservoir appropriately, you'll want to have all pistons pushed out and in contact with the pads, otherwise you risk under-filling the master cylinder.

Dan H.

Thank you guys. My logical thought process tells me it shouldn't matter. I wanted to check because I have a lot of examples where I assumed and should have asked.

I use a motive power bleeder. I'll pump the pedal a few times without the car running and go from there.

Thanks again - Really looking forward to my first 2015 event!

ErnieN85

next time you push the pistons back put a bleeder bottle on and open the screw that way all the old nasty stuff in the pistons get pushed out in stead of up the lines and then righ back into the pistons.