Looking at the (2001 VW Golf TDI) manual, it only has instructions to bleed when air is in the system.
How to flush out old brake fluid and fill up new? Do I need to take off all
4 wheels and open all 4 bleeding ports? Pump with pedal? When to fill the new fluid?I read that if the system is really empty, I will generate an ABS error message, need to reset in computer... Please help.
You generally don't empty the system & then refill - you just bleed enough fresh fluid through each wheel to be sure you have replaced it all. You need to take the most out the first wheel because that clears out the master cylinder. Before you start take all the old fluid out the reservoir & refull with fresh fluid. Something like a turkey baster works well. Usual bleeding sequence is RR, LR RF & LF & don't forget the clutch if that's hydraulic. Keep an eye on the reservoir as you go & top up as necessary. Power bleeders make the job a whole lot easier.
In total you will use between 2 & 3L of brake fluid as a rough guide.
I.
You want to get out as much as you can but at the same time you don't want to get air in there either.
That's what it usually works out to. the rule is start w/the one farthest away from the M/C and doing the one that's closer last...so yes...RR, then LR, then RF, then LF.
When pumping the brake pedal, try not to push it down too far. I've heard that if the piston travels farther than it usually does under normal braking it can damage internal seals etc. inside the M/C. Better to do more shorter pumps in the normal range of travel rather than longer pumps in an extended range of travel.
Indeed so.
True - sticking a block of wood behind the pedal to limit the travel is the safe way to do it. This is also one of the best arguments for using a pressure bleeder (or having one of those convenient cars that will allow you to use the ABS pump to pump the fluid through!)
I.
Some piece of transparent plastic pipe (from a hobby store?) will greatly help to do it comfortably. Just put one end of the pipe onto the bleeding screw, another into some bottle and you are set to go. This will keep the system from accidently sucking the air, and at the same time you can see when the fresh brake fluid starts to come out (that's when somehow darker fluid starts to become crystal clear). And you avoid all the mess, as the brake fluid is highly toxic and agressive.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.