Spongy brake pedal after winter storage

[mp470]

Hi all,

Big red is coming out for the spring and i have no brakes. The larger part of the reservoir was empty for some reason and I have replenished it. Did not see any leaks at the master cylinder though. The pedal goes to the floor only when the vehicle is running but pumps up fine when off.  I did a stupid thing and left the e-brake on all winter so the light is on but I don't think it's related.  Please and thanks for any suggestions.

[Gary Lewis]

You might want to read this post, or the whole thread for that matter.

As for the e-brake, sometimes that moves the shoes out so far it lets the pistons get into a rusted area of the brake cylinder, and causes leaks to start.

[mp470]

Thanks. I suspect the master cylinder seals went from the extreme cold of our winters (-40C at times) and it's leaking internally as I didn't see any leaks at the wheels either.

[Gary Lewis]

That might do it.  I think I'd lose my seals at that temp.  

[mp470]

New cylinder did it, leaked out internally and through the rear. When bleeding the two rear brakes, couldn't get much to come out though. It wasn't a dribble but not the powerful flow I'd expect with as much vacuum as was applied. Tried with a vacuum pump to 20-25 psi and the manual method.  Couldn't do the fronts as they face forward for some reason and had no way to get wheels off out there. Nonetheless, the pedal is good enough for the road now.

[Gary Lewis]

Did you bleed the master itself?  See Page 12 here: Driveline/Brakes and on the Factory Shop Manual tab and then the General Brake Service tab.  (That's a new section, so you didn't miss it.)

[mp470]

I sure did, on the bench before installing. Wish I could've tried the fronts to compare.

[Gary Lewis]

Ok.  Might the fronts be swapped side-for-side?

[mp470]

Never crossed my mind, are the bleeders supposed to face the rear?

[Gary Lewis]

I'll check the shop manual tomorrow to see if it says which way they should point.

[Frank Wyatt]

The bleeders on my front brake calipers face forward, and they can't be swapped from one side to the next. If they were your bleeders would be on the bottom and would make bleeding out any air in the system impossible.

[Gary Lewis]

Good to know.  Thanks.

[Frank Wyatt]

It's been done before at least on a Dodge that I saw on You Tube, and they mixed up all 4 calipers.