I finished swaping out my master brake cylinder from 17 to 19mm, no leaking. I keep pushing down the brake pedel with no resistance. If I keep pushing it down, will I eventually feel resistance or do I need to bleed the brakes first?

I pulled the new master cylinder and did not do anything before mounting there isn't anything special I should have done to it should I?

Feedback is appreeciated.

Thnx
Brian

Yes you need to bleed your brakes, a bunch!

Some recomend bench bleeding the MC when you replace it, but I have no idea how you would do that. I put mine in dry then bleed the brakes

oh, and stop bottoming out on your MC while it is dry, you can damage the seals.

I would at least bleed the left front caliper first to purge most of the air from the line and M/C. The last thing you want is to get air into the rear proportioning valve.

Then start bleeding at the furthest caliper and work back to the LF.

I think I ran a good quart of fluid through the system when I replaced my MC. Speed bleeders are a great help. Use the top bleeder.

Just learned how to bleed my brakes a month ago... so I'm not an expert but this technic worked really well.

Go buy 25' of clear irrigation hose (I'm pretty sure I got 3/8" ID, but it could have been 5/16") any way you could take a bleeder nipple with you to test fit.

I don't know what the best order is for which caliper to bleed first- but essentially hook up your 'return' irrigation hose to the top bleeder nipple on the caliper and run the hose back to the brake fluid reservoir and secure it in place so it can pour in there.

Loosen the bleeder nipple 1/4 to 1/2 turn... pump away on the brakes, monitor the bubbles in the hose (you want them all gone) and stop every 10-20 pumps to make sure you still have plenty of fluid in the reservoir (don't let it go dry!)

use nails (and elevation control) to plug the hose while you swap it between calipers.

clean up any spills since brake fluid smells sweet to animals but is highly toxic.

that's how you can bleed your brakes without an assistant. Super easy and fast and now I have a super firm break pedal.

1.) Fill brake fluid reservoir.

2.) Crack lines leading from MC to brakes and let it drip for a period of time (you can slowly push on pedal also) to fill the MC ... This assumes you have the push rod centered correctly.

3.) Tighten MC connections.

4.) Starting with caliper fartherest away (Pass side rear to you), start bleeding.

5.) Move to Drivers rear.

6.) Move to Pass front.

7.) Move to Drivers' front.

8.) Repeat 4 - 7 as many times as necessary.

I use a vacuum pump. Some use a pressure bleeder. Some use somebody elses' leg.

We've heard that about you...

You should have taken it to a mechanic............



(Brian - check the local board about the caravan out)

This is the technique I have used for a long time. But before you start 'recycling' fluid, make sure you flush each line with clear fresh fluid. Old fluid needs to be replaced not just bled.

I would start by spending a lot of time with the line hooked up to the drivers front caliper. You want to bleed all of the air out of the MC first. You should spend a long time pumping fluid. This will take more than 5 minutes. Think, more like 30 minutes. And this is why recirculating fluid is so handy, your reservoir won't go dry and you don't need an assistant. Just pump and pump and pump some more. If you get a long enough line (15' should be good), you can route the hose so you can see any bubbles that are coming out. Remember that you'll see no bubbles for a long time, and then every once in awhile a little one will come out. So keep after it. Also, I've found it helps to close the bleed nipple every once in awhile and slowly pump the pedal. This causes pressure fluctuation in the system that can free up some stubborn bubbles.

Good luck!

Well done sir.

I thought of doing something like this before but I think your hose would hold alot of fluid before. i have to bleed my breaks again. I had to rebuild a caliper and after putting everything back together and bleeding, the pedal is still not as tight as it was before. Pretty close but not as good.

I bought the solo bleeder valves and put three of them in. I twisted off the fourth nipple. It didn't want to budge. So it will need to be drilled out and I don't have the stuff to do that.
Bleeding breaks sucks on older cars.