Brake fluid flush + slave install

[MacaveliMC]

Hey guys quick question for those of you who have done a brake fluid flush and also replaced your slave.

I'm gonna replace my slave soon with the extended one, and I'd like to also do an entire flush as well. I'm just trying to figure out exactly how to do it correctly at the same time.

The video on youtube for how to use the power bleeder says to evacuate all old fluid from the reservoir first, then fill and connect your power bleeder, and pump it for pressure. So my questions are:

Will the power bleeder fill the reservoir enough to reach the connection point for the master cylinder? I know it's high in the reservoir and you need a high fluid level to properly bleed the slave cylinder.

Should I bleed the brakes in order from farthest to closest first, or can I bleed the slave first?

I was gonna try to pull all the fluid out of the clutch system from the old slave bleeder using a vacuum hand pump before I disconnected the slave and replaced it, to reduce mess. Do you think this is a good idea?

Just trying to figure out the correct order to do all this in to make it quick/efficient and reduce headaches/problems.

Thanks for the input!

[agentsmith988]

Hey guys quick question for those of you who have done a brake fluid flush and also replaced your slave.

I'm gonna replace my slave soon with the extended one, and I'd like to also do an entire flush as well. I'm just trying to figure out exactly how to do it correctly at the same time.

The video on youtube for how to use the power bleeder says to evacuate all old fluid from the reservoir first, then fill and connect your power bleeder, and pump it for pressure. So my questions are:

Will the power bleeder fill the reservoir enough to reach the connection point for the master cylinder? I know it's high in the reservoir and you need a high fluid level to properly bleed the slave cylinder.

Should I bleed the brakes in order from farthest to closest first, or can I bleed the slave first?

I was gonna try to pull all the fluid out of the clutch system from the old slave bleeder using a vacuum hand pump before I disconnected the slave and replaced it, to reduce mess. Do you think this is a good idea?

Just trying to figure out the correct order to do all this in to make it quick/efficient and reduce headaches/problems.

Thanks for the input!

I did this a few weeks ago. Used a Sachs slave and 2 liters of ATE DOT 4 TYP 200 Brake Fluid from FCP Euro.

Removed the old fluid from the reservoir with a syringe, added some new fluid to the reservoir (not sure if necessary), swapped the slave, and pressure bled/flushed (with the power bleeder filled with new fluid) at 15-20 psi until clean fluid came out at the slave. I then flushed the brakes at 15-20 psi (right rear, left rear, right front, left front). I finished up with one last quick bleed at the slave and was done. I connected some 1/4" ID tubing on each bleeder port to drain into a bottle while bleeding to avoid any mess.

Don't worry about fluid loss/mess when swapping the slave. Barely anything comes out with the reservoir still capped.

During the entire process make sure you don't run the reservoir dry or you'll have a bad day.

[MacaveliMC]

I did this a few weeks ago. Used a Sachs slave and 2 liters of ATE DOT 4 TYP 200 Brake Fluid from FCP Euro.

Removed the old fluid from the reservoir with a syringe, added some new fluid to the reservoir (not sure if necessary), swapped the slave, and pressure bled/flushed at 15-20 psi until clean fluid came out at the slave. I then flushed the brakes at 15-20 psi (right rear, left rear, right front, left front). I finished up with one last quick bleed at the slave and was done. I connected some 1/4" ID tubing on each bleeder port to drain into a bottle while bleeding to avoid any mess.

Don't worry about fluid loss/mess when swapping the slave. Barely anything comes out with the reservoir still capped.

During the entire process make sure you don't run the reservoir dry or you'll have a bad day.

So you said you removed the old fluid from the reservoir, but you also said don't run it dry....so how much did you remove?

[agentsmith988]

So you said you removed the old fluid from the reservoir, but you also said don't run it dry....so how much did you remove?

Exactly. Don't apply the brakes or push the clutch pedal with the reservoir empty. It can be empty while you're swapping the fluid. Static hydraulics aren't going to cause an issue.

Make sure the power bleeder has fluid in it when using it as well if that wasn't clear. That will keep the reservoir full as you flush the system.

[MacaveliMC]

One more question: I'm finally about to do this today, and I'm assuming I only need to remove the rear underbody cover/panel correct? Any idea how many or what types of bolts they are?

[agentsmith988]

One more question: I'm finally about to do this today, and I'm assuming I only need to remove the rear underbody cover/panel correct? Any idea how many or what types of bolts they are?

There's a combination of torx screws, ones you can get with a flat head, and a spreader rivet that you'll us a flat head to remove as well. Simple stuff!

[MacaveliMC]

Thanks, when you did this did you connect the new slave and bleed it BEFORE installing it in the transmission? That's what the installation guide for the extended slave seems to imply, just wanted to make sure it's OK to have that 3-5 PSI pressure on the line when the slave has nothing to push against.

[agentsmith988]

Thanks, when you did this did you connect the new slave and bleed it BEFORE installing it in the transmission? That's what the installation guide for the extended slave seems to imply, just wanted to make sure it's OK to have that 3-5 PSI pressure on the line when the slave has nothing to push against.

Correct. Bleed with the pressure bleeder before reinstalling into the transmission bell.

[MacaveliMC]

OK, I successfully completed the install of the extended slave, and so far the car seems much better! The clutch seems to return better (altho could probably still be improved a tad, maybe with stiffer clutch springs?), and no push to start issue in the 3 or 4 times I've started the car since!

Overall it was not bad. I found out someone put the metal slave cylinder on this car, and recently because it had a time stamp on it from 2019! The car still had the pick up line between the clutch line & the slave which I was surprised about, but my buddy who was helping me did some quick searching and said he found out that when you use the metal slave you HAVE to use the metal pick-up line. Since I was putting in the plastic extended slave, I decided to remove the pick-up line and connect the clutch line directly to the slave (pretty much a weight reduction [:D])

The hardest part was definitely removing the slave from the trans housing. Not sure if that's true for all of them, or if this is unique to the metal slave. I yanked and yanked and yanked. I don't remember how I eventually got it out....I think I put a screw driver through the bolt hole and was able to squeeze two hands up there, grab both sides, and brace myself enough. Even then, only the body of the slave came off. The rod & the boot were still inside the hole. Pulled the rod out easy enough, but I had to use needle nose the grab the boot carefully so it didn't get lost in there [o_o]

Connected the new slave to the clutch line, and bled using the power bleeder. It's really strange, all the bleeder screws on this car have to be opened quite a bit to get them to bleed. I'm so used to just cracking a bleeder and having it flow. Had to give the slave bleeder & all the caliper bleeders a couple turns to get a good flow. Maybe I'm just not used to the 3-5 PSI of the power bleeder, vs when I bleed my motorcycles using the master.

Anyway, put the new slave in once it was bled. It went in so easily I was concerned I didn't line it up right, but sure enough the car started perfectly.

Then I bled all the brakes, and everything seems to be working great! Thanks so much for the help guys. Had to come back and write about my experience, in case anyone else has any questions they can read this conclusion. Here's a picture of the old slave & pick up line. Put it back together for the picture lol

EDIT: Looks like it was probably the USP Motorsports B8 Clutch Line & Metal Slave Conversion Kit that a previous owner installed. That's what the clutch line looks like.

[agentsmith988]

Good work!

You only used 3-5 psi for bleeding? I always use 15-20 psi and I believe that's the recommended range.

The screws do take quite a bit of turning though.

[MacaveliMC]

Good work!

You only used 3-5 psi for bleeding? I always use 15-20 psi and I believe that's the recommended range.

The screws do take quite a bit of turning though.

Oh I know why I did that. Because the installation guide on the JXB performance site says to use 3-5 PSI lol, not sure why.