Mstr Cyl/brake ??(wearing stupid hat)

[Randy Whistler]

First, thanks to everyone who answered my A/C questions. Now, of course, the 'Hoe has another issue.

I've done brakes a long time, so I'm not unfamiliar with repair/replacement. However, I hadn't noticed my master cylinder getting low on fluid until the pedal seemed to travel a little too far down. I think I caught it before it ran dry(I hope) but not sure. I know that it could simply be time to replace pads on either front or back with the pedal seeming to go too far down, and it could just be I'm imagining it, as the other vehicles I drive regularly have a firmer pedal than the Tahoe does - and has always, not something new. I have tried pumping the pedal when running, and it does NOT change the feel, leading me to believe there is no air in any of the lines. When not running, it does pump up firm and holds, which I take as a good sign. I also know that i have a tiny leak in my line underneath the drivers side that I'm going to attack tomorrow. It does not appear to leak without pressure applied to the line, and only seems to ooze a tiny bit when pressure is applied. That makes me think that it's been leaking for some time and I just hadn't caught it until now.

Since it does not appear to have any air in the lines, based on my experience and testing, I'm hoping that if the leak can be tightened rather than a replacement, then it becomes something like pad replacement, etc. I'm sure if it ran dry then bleeding would be a requirement but I don't know if it got that low or not. Refilling has not changed the operation any, other than having fluid in the reservoir.

Wonder if that Flex Seal stuff the advertise on TV would seal up the leak? J/K, but the advertisements do make you wonder how well that stuff works!

TIA,

 

[OR VietVet]

I would bet the softness is related to the leaking line. The pedal holds firm as long as ALL hydraulic pressure stays in the lines and calipers and in the master cylinder. It may be seepage of fluid at that line but still some of the pressure is bleeding off because of the leak.

 

[Randy Whistler]

I would bet the softness is related to the leaking line. The pedal holds firm as long as ALL hydraulic pressure stays in the lines and calipers and in the master cylinder. It may be seepage of fluid at that line but still some of the pressure is bleeding off because of the leak.

Thanks, that's exactly what I thought as well! Or what I had hoped, any way. . . glad I may be on the right track.

 

[PNWYukon]

Pads, Rotors, check calipers and pistons and seals, fix all leaks at each caliper, then bleed each caliper starting at passenger rear, driver rear, passenger front and driver front.

If the lines are leaking then replace soft lines. Brakes are too important.

 

[wjburken]

Also check your rubber brake lines at each wheel to make sure they aren’t ballooning on you.