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Master cylinder resivoir question

Blaine B.

NAXJA Forum User
So I put new pads on today. I left the brake cap off so I could depress the caliper pistons, yadda yadda yadda. So when the brakes are all back on, I press the brake pedal a few times so I could see where the brake fluid level was once the pads were seated.

Well it turns out I forgot to put the cap back on! The resivoir had plenty of fluid, never ran dry.

However my question is, is it possible that air got into the lines/master cylinder from me pumping the brakes with the resivoir cap off?
 
Blaine B. said:
So I put new pads on today. I left the brake cap off so I could depress the caliper pistons, yadda yadda yadda. So when the brakes are all back on, I press the brake pedal a few times so I could see where the brake fluid level was once the pads were seated.

Well it turns out I forgot to put the cap back on! The resivoir had plenty of fluid, never ran dry.

However my question is, is it possible that air got into the lines/master cylinder from me pumping the brakes with the resivoir cap off?

As long as the ports on the bottom of the reservoir stayed under fluid, no. That's why they're on the bottom - you have to run the cylinder dry before it will suck air.

It may not be a bad idea to suck most of the fluid out and replace it with fresh (nothing to do with what you've done - brake fluid is, as you probably already know, hygroscopic. I change mine every two years,) but that's about it.
 
Yes, I was planning on changing out my brake fluid (entirely) soon and bleeding all of the lines.

It just feels like the pedal is alot mushier now. I know my rear shoes are worn but I did readjust them, and the star adjusters are working. I also lubed the slide pins and rails up front. I was just suprised to not get a firmer, higher pedal with new pads like usual. I thought it must have been because I pumped the brakes with the cap off of the res.

Well, time to investigate further....
 
Check for soft spongy brake hoses on the front also. they tend to rot from the inside out.
 
5 months old for the front hoses. Not sure about the rear.

But what I really need to do first is get new shoes for the rear and then completely bleed the system until it comes out clear from the new Dot3.

It's not that the pedal feels spongy.....I don't know, just doesn't seem as if I am stopping as quickly as I should. Maybe the rear worn drum brakes are partly to blame.

my caliper slide pins were really stuck. I did remove them and lube them up with synthetic grease (for disc brakes, etc) and also sanded down the rails and greased them. I do have a few notches on the rails but I smoothed them out.

EDIT - Also my front rotors SUCK. Need new ones as well. Stupid Chrysler recall replacements warp so fast....bah.
 
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