Getting ready to replace my Master Cylinder on a 95 Sidekick.  Anyone know of an upgrade that will bolt on? I am losing brake pressure when stopped and occasionally the pedal goes to the floor and the "brake" light comes on... anyone else had this?

Getting ready to replace my Master Cylinder on a 95 Sidekick.  Anyone know of an upgrade that will bolt on?

Have you upgraded the brakes to something that requires more volume than stock (larger calipers? rear disc?).  If not, you're putting the cart in front of the horse.  If you're stock, put a new stock M/C in.

Okay, so I replaced the it with a used stock MC.  Same problem still  losing pressure and the pedal slowly falls when stopped.  It seems to hold pressure just fine when the engine is not running. It stops okay and no brake light is on the dash but they seem mushy and again lose pressure.  I thought the MC replacement woudl fix this but apparently not.

Anyone else run into this problem?  I am going to re-bleed the lines and see if it is air causing mushiness... but the losing pressure thing and sinking pedal has me stumped.

Never discount the possibility that the used MC is bad as well.  Many of these are pushing 15-20 years old.

yeah.... Are there any rebuild kits avail for these... Or again a cheap alternative?

Here's a twist.  I found that when turning full turn to the left, I lose ALL brake pressure and brakes. However, pump the pedal and it all comes back.  It doesn't do it to the right, only the left. And it does it with both master cylinders so I don't think it is the MC. 

Has anyone heard of this?

I had spongy brakes for a while... then I discovered that one caliper slide was missing and the other was loose on the driver's side where I did some bearing work recently.

Installing a new set fixed that little problem .

Also, a replacement master cylinder is always a more reliable deal than a used one.  Most auto parts stores have a "lifetime" warrenty on their parts.  If it does not work, take it back and get another one.

Be sure to follow the instructions packed with the unit dealing with bench bleeding!

BRD HNTR had a similar issue with the brakes going out when he was wheeling.  The spring was pushing up against the caliper and compressing it, you might be seeing a similar issue.  Turn all the way to the left, then go under your vehicle and check to makes sure nothing is pushing up against the calipers.

I bet thats it... what was the fix?

I bet thats it... what was the fix?

He modified the spring seats in the wishbone to get the spring sitting straighter. You should be able to adjust the steering stops to prevent it.

I probably need to go back to the 1.5" Jeff spacers to reduce spring bowing.  Do you know if OME springs bow less than stock one with spacers?  That has to be the issue. 

Here's the update... I have two problems. One is that I bought a bad master cylinder and two, the spring does hit the caliper. I went back to the 1.5" this morning so we should be okay with issue #2.  Now, why is it so hard to find 1995 4 door master cylinders?

More on the master cylinder saga... Broke down and bought a re-manufactured MC from the local parts store. It came with instructions and some bleeder nipples and small lengths of tubing. The instructions say NOT to bench bleed it but to only bleed on the vehicle then it goes on to describe a very elaborate process of bleeding with these bleeders included in the kit. Well, the bleeder nipples (plastic) don't seem to be the right thread size and will not fit. Has anyone done this? Is it necessary to bleed like this or can I slap it on and start pumping away with my mightyvac hand pump??

Also, here are the photos of the springs with the 1.5" Jeff's spacers and the 2" showing the spring bow

looks like I was correct in your bumper thread!! in a way I am happy I was, because now it forces me to modify my spring pad like BRD HNTR. let me know if switching back to the 1.5 spacers fixes this.

I feel bad for having the same topic going on two threads... as soon as I figure out the new master cylinder I will test drive and let you know!