Brakes

[muleskinner]

I had recently replaced the proportioning valve on my blue festy because I was told it was bad when I got it. Now it seems the left rear and right front has hardly any brake pressure & when I bleed them air and fluid mix comes out. Plus I hardly have any brake peddle. I hardly had any brake before this now its worse. Could it be a bad Master cylinder? .... I'm at a loss here....

[FestYboy]

Possible, but first check all plumbing joints for wetness, and double check the they're tight.

[ryanprins13]

After that^ how new are your wheel cylinders? What condition are the hoses in? Ive been told that really old seals on wheel cylinders can sometimes seal against pressure but let air back in when you let off the brake.
What are you using to bleed brakes? Just 2 people and a wrench or a bleeder tool?

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[muleskinner]

Checked all the connections, looked at the wheel cylinders. I see no leaks & the cylinders appear to be ok.
We were bleeding the brakes with a wrench and someone pumping and hold while bleeding. Everything was going as planned. Was getting good brake peddle then suddenly the peddle went almost to the floor. Now when bleeding there is fluid with bubbles coming out of the left rear & right front.

[FestYboy]

Bad master seals from the fluid flush. I see it quite often, especially with older cars that never had their fluid changed. Gunk and corrosion build up on the part of the bore that isn't typically used, so when you DO flush it, that junk destroys what's left of the cup seals. Replace the master... with an upgrade.

[muleskinner]

I just replaced the master cylinder with one I know works for now and it's still doing the same thing!!! Grrrr!!

Could the proportioning valve gone bad that I put in? It was from another festy that had good brakes,

[firebush357]

I had a Proportioning valve spring a leak in one but it would shoot brake fluid about 4 feet in the air when I got the system fully pressurized.

[bravekozak]

The brakes must be bled in the following order:

Right rear
Left front
Left rear
Right front

The proportioning valve proportions diagonally.

[muleskinner]

fixed!

Slightly loose line on the proportioning valve. Strange thing, it wasn't leaking.

Thanks for the responses & help!

Of course NOW the car will not start. it clicks like its a starter issue. It has a new battery.

[firebush357]

The brakes must be bled in the following order:

Right rear
Left front
Left rear
Right front

The proportioning valve proportions diagonally.

Didn't know that... I always just started with the furthest from the MC and worked my way up.