master cylinder install question(another one)

got the old one out(73) when i bolt the new one in do i just connect all the lines and fill resevoir with fluid and let gravity take over before bleeding or is their a trick to getting air out early.

Bench bleed the mstr cylinder -

http://www.vw-resource.com/bench_bleed.html

I've never had a lot of luck gravity bleeding a VW system. Gravity works great on most British cars, but VW's seem picky.

Even if you have access to a pressure bleeder (which work GREAT, BTW) I would still use Wolfgang's link and bench prime the MC before installation. Otherwise, sometimes it's a devil of a time getting the system bled.

Bench Priming looks like (and is) a PITA, but it's an even BIGGER PITA to try to get the system bubble-free without priming first.

Plan on using at least 1 quart of fluid for the entire priming/bleeding process and DO NOT re-use any fluid.

I made my own pressure bleeder by drilling a hole in a variety of caps that fit just about evey combination of VW reservoirs I then mounted a metal vlave stem in the cap and removed the schrader valve.
I have an air chuck that is used by Tire mounting shops and has a lock on the chuck and doesn't require a shrader valve to to allow air to pass through the chuck. (This is the kind of air chuck tire shops use to inflate a tire until it seats on the safety bead. Once they remove the chuck, air comes rushing out the valve stem until they install the shrader vavle) I

turn my compressor down to about 10 to 15 PSI Attach the air chuck to the valve stem then bleed the brakes. Works great and it didn't cost anything to make.

Bob,
Larry has a great idea there - I used a system I found on one of the VW help lines. I used a garden sprayer w/ the hose hooked up to a brass nipple threaded through a plastic cap of a regular oil can. It fit the cap of my brake fluid holder and w/ about 5 to 10 pumps on the garden sprayer I can bleed the hole system w/o pumping the brakes. I replaced two master cyl's before I figured out that it was the bleeding process that was kicking my butt. VW's are real hard to bleed the normal way. It also gets rid of those bubbles that Cory was talking about on the other post. You can bleed the brakes w/o help this way.
Let me know if you need more help to make one.
Dale

Brake bleeding made easy:

http://www.bmw-m.net/TechProc/bleeder.htm

gn

Gordon,
Yep that's it.
Worked great for me except I used the top off a 1 qt oil can and it fit my VW bug brake fluid canister - use a rubber washer inside to help it seal better.

I guess I should have patented my cheapo brake bleading system back in the early 70's when I first experimented with it.

After bench bleeding, are there check valves inside the cylinder that keep fluid from leaking out while you are installing the cylinder?

No....just put the ust caps back in while you move it, then pull'em out and install the threaded tububg ends.

No more wine before typing, Gordon.

Gordy - that must be how you do your master-cylinders when you're ON CRACK!!!

GN...youz went to the same typing school as me !