Just got a used '02 F4i - there is no fluid in the front brake system. I read the manual and it says to have a mechanic do it so no air gets in the lines, or they have to be bled. Is this really something you need to take to a shop or is it an easy DIY job?

 

Adding fluid to your brake reservoir can be a simple as taking the top off and adding fluid to the full line then replacing the top. If your brakes feel good before the resivior was full then bleeding the brakes is probably not necessary after filling the resivior. If your brakes feel mushy then they need bled and it is a DIY job if you know what you are doing. If you personally don't know what you are doing then get a friend who has bleed brakes before.

The process is as simple as loosening the bleed valve on the caliper and connecting a clear hose from it and running the hose into a small clean container of clean brake fluid. You then pump the brake lever to get all the air out. The point is to have the system filled completely with fluid and no air what so ever. While you pump the brake lever you fill the brake reservoir making sure it doesn’t get low enough to let air get into the brake lines. You continue pumping and filling until you no longer see air bubbles coming out of the clear hose that is connected to the bleed valve. When you are sure there is no air you tighten the bleed valve, fill the reservoir to the full line and put the top back on. If you did everything correctly you should have a good solid feel when you squeeze your brakes.

There are brake bleed valve replacements called Speed Bleeders that only allows the brake fluid to be bumped out of the caliper when you pump the lever prohibiting air to back up into the caliper. Do an internet search for them. They are worth the money because they make bleeding brakes an easy one man job.

 

That was a good write up but you weren't clear on how to pump and bleed. When you're doing it you want to pump up the lever until its firm, then have a friend open the bleed valve while you squeeze the lever down to the bar. Then before releasing the lever have him close the bleed valve so you don't suck any air into the system. PM me if you need more details.

 

Mity-Vac also makes a brake bleeding kit.. basically its a pump system. I had one when I put braided lines on my FZR. I've done the old pump and squeeze method before and it sucks! especially if you get air into that master cylinder. But then again do you want to spend apx. $30ish for the Mity-vac thing? IMO i would have a friend do the pump and bleed method and save yourself money.. KEEP A CLOSE EYE ON THE FLUID LEVEL UP TOP WHILE YOU'RE BLEEDING DOWN BELOW.. good luck!