I did a zf swap on my 325 a while back and wanted to update on my issues with bleeding the clutch because I’ve had people ask me about it a few times. I used a 325i clutch kit and 325i slave, the master was the shorter one out of a 1998 and up 328i.

So for my method you will require a soft clutch line, either a 2 piece one with a delay valve or a 1 piece one from bimmerworld, the one piece one definitely feels a little different without the delay but it is totally fine as long as you’re not drifting. You will also need a power brake bleeder, they are like 50$ on amazon for bmw.

Install the line onto the master cylinder as well as the feed line from the reservoir but do not hook it up to the pedals, so it’s just hanging in by the clutch pedal, then pull it away from the firewall and tilt the master upside down so the piston is facing downward, you could cycle it by hand a few times or now put the power bleeder on, it is fine if the slave cylinder is hooked up right now just make sure the bleeder is open, I prefer to let the line just shoot fluid everywhere and make a mess before I install the slave.

Now the bleeder will push fluid through the master from the bottom, this prevents air bubbles from trapping themselves at the top of the master cylinder, you might also just want to move it around some so you are really sure there’s no air trapped, if you do it by hand replicate the same thing and keep it upside down and cycle the piston, give it a few minutes or however long you like, then install the line to the slave.

Now the slave is hooked up so that now needs to be bled, so first I would install the slave onto the transmission, making sure the rod contacts the clutch fork, you should feel a bit of resistance when installing it as the piston has to compress even if there is no fluid in it. Now put the bleeder back on and open the valve on the slave. Continue to let it bleed for a while.

Once you think it’s almost ready, turn the bleeder off and remove the slave from the transmission, you now are going to hand bleed the slave, so open the valve and compress the piston then close the valve before letting it up. Do it a few times then install it back onto the transmission. And maybe give the power bleeder another go for a bit.

Now install the master onto the clutch pedal and you should have a clutch that works. If the engagement is still very close to the floor, continue to bleed it until it is where you are comfortable to drive with.

If you have any questions message me on instagram
@charlesmoreland07


Sent from my iPhone using Tapatalk