[razzle45]

So I'm changing my brake fluid with RBF600 and I'm running into issues. The first time I did a leak test with a Motive Bleeder and the pressure was dropping but I went ahead and changed the fluid regardless lol. However, I went at it a second time and flushed the fluid again. The second time around I pushed the pedal on top of putting pressure with the Motive bleeder. After the second flush, the motive bleeder is now holding pressure.

The strange part is when the car is on the pedal doesn't get firm until it reaches full travel. But when the car is off it get hard relatively quick. I didn't notice this until of course after I was done bleeding all of the calipers. I'm certain something is wrong here but I have no idea what else I could do.

Has anyone run into anything similar or any experts have any advise?

[RCM78]

There’s air in the system.
Find out the proper procedure for bleeding the system.
Also, RBF600 will absorb moisture faster than regular dot4. Be prepared to flush it more often.

[prostcfc]

Originally Posted by razzle45

But when the car is off it get hard relatively quick.

This is normal and is a function of how brake boosters work when the engine is on versus off.

The Motive bleeder is kind of hard to screw up, I've used it myself many times. The main way I can think of introducing air is if you take a pressure test with an empty brake reservoir, or let the reservoir run empty when bleeding for any reason (I make sure and pull all the old stuff out first, then fill with new stuff, then pressure test. I make sure the Motive bleeder and the reservoir aren't empty while bleeding).

[razzle45]

I followed all the directions you see on youtube for the Motive bleeder except I continued with the process even though my pump failed the leak test. From what I recall, it never got to the point where the reservoir was empty.

As it sits, could someone give me step by step instructions on how to get the air out?

[razzle45]

Originally Posted by razzle45

I followed all the directions you see on youtube for the Motive bleeder except I continued with the process even though my pump failed the leak test. From what I recall, it never got to the point where the reservoir was empty.

As it sits, could someone give me step by step instructions on how to get the air out?

I know its a really basic thing and I'm no mechanic by any means but I enjoy learning how to maintain something when you "abuse it". Would really appreciate if anyone could guide me.

[Bc2005]

It sounds like the Motive bleeder has a leak. However, it’s seems that would just reduce the bleeding pressure and slow the process.

If you have a friend who is good at following directions, you can bleed brakes manually.
- Fill the reservoir up to the very top
- Friend pumps and then holds firm pressure on the brake pedal
- with a hose on the bleeder running into a 1/2 full container of brake fluid, you crack open the bleeder and watch fluid and bubbles come out.
- close the bleeder and go up to check and refill the reservoir
- repeat the process until you see no bubbles at any wheel position. Never let the reservoir go empty, because then it sucks in air.

[razzle45]

Originally Posted by Bc2005

It sounds like the Motive bleeder has a leak. However, it’s seems that would just reduce the bleeding pressure and slow the process.

If you have a friend who is good at following directions, you can bleed brakes manually.
- Fill the reservoir up to the very top
- Friend pumps and then holds firm pressure on the brake pedal
- with a hose on the bleeder running into a 1/2 full container of brake fluid, you crack open the bleeder and watch fluid and bubbles come out.
- close the bleeder and go up to check and refill the reservoir
- repeat the process until you see no bubbles at any wheel position. Never let the reservoir go empty, because then it sucks in air.

Would I do this while the car is off or on? Because like I said the second time I did a combination of this with the Motive bleeder but maybe it makes a difference if I just did this instead of doing it in combination.