sticky brake peddle (75 Dodge PU) Power Brakes

after giving my 75 Dodge the winter off. i went out to wake her up for some spring cleaning and a trip to the Dump. the Old Girl started up just fine : ) but when i put on the brakes the peddle was (vary hard to push) and (wouldn't return) the peddle stayed down making the brakes lock.. it felt like a broken return spring or somthing.. i could still drive the Old Girl but i would have to pull the peddle up by hooking my foot under the brake peddle to release the brakes..... my first thought was the linkage and rod from the peddle to the master-cylinder was in need of oil... i crawled under the dash with a squirt can of oil and WD-40.. but that didn't work.. i then went under the hood and loosened the (Master-Cylinder nuts) to the (Power-Brake-Booster) 3 or 4 turns to see if the plunger rod was binding between the Fire-Wall or Booster.... i pumped the peddle a few times hoping it would free up.. NOPE the brake peddle still doesn't return after depressing it... so my QUESTION is... #1. could it be a bad Vacuum-Brake-Booster?? #2. how do i check the BOOSTER?? #3.can a BOOSTER be Rebuilt?

Reply to
John G
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Possibly but unlikely. If the booster was the cause, pulling up on the pedal would not release the brakes.

I would remove the booster and check the pedal for free movement then. If it moves freely then the booster is the probable cause and if not, look where the linkage comes thru the fire wall for corrosion there and make sure that no wired came loose and are jamed up in the linkage under the dash.

Nope.

Reply to
TBone

Replace the master cylinder and flush the water out of the system. Use DOT 4 fluid or if you really want to prevent water problems, DOT -5 Silicone Fluid.

Reply to
Budd Cochran

I've heard that DOT 5 fluid is best if your vehicle sits for long periods of time. Some people say you have to flush the system completely with alcohol before switching to DOT 5, and some will swear that you do not. I'm not sure if it's really necessary but I think I'd take the time to do it anyway just to remove any doubt. If I suspected I had moisture in my brake system and was going to flush the brake lines anyway, I'd go with DOT 5.

Reply to
Nosey

Rick Ehrenberg (S.A.E.) of Mopar Action says to just flush it thru. He uses it in the Green Brick 67 Plymouth Valiant.

Reply to
Budd Cochran

it has DOT-5 fluid in it... i really don't think the problem is in the master-cylinder... the fluid is vary clean and the brakes work fine... it feels like the (power) brakes aren't working... again:: the pedal works vary hard and i have to pull up vary hard with my toe to fully release the brakes.. take no offence but i still think the problem is in the Vacuume-Booster.... but i have been wrong before...lol.. i will take your advice and bleed the brakes out tonight and post the results.... Thank you : )

Reply to
John G

John,

Hmmm, it looks like I goofed a bit ... I missed the pedal lifting part . . my bad. (smacks left hand with right hand) My apologies.

Check the vacuum line to make sure it isn't cracked between the booster and the engine. A bad line would prevent having any boost.

I took a peek into my son's Haynes manual and I didn't see any return spring on the pedal itself, however, there might be one on the booster to return the pedal. If it is supposed to use a clip on the push rod to bear against, the clip might be gone, rusted through, or slipped out of it's groove.

Reply to
Budd Cochran

Since there is no mechanical link between the MC and the booster it's unlikely that the MC is the problem; to be sure, back the MC attach nuts way off and pull the MC away from the booster enough to expose the pushrod. If the pedal still sticks with the MC disconnected the booster is the problem.

BTW, the booster IS rebuildable.

Reply to
John Kunkel

I knew you could get parts to rebuild them many moons ago, but I had figured that those, like many other things, had gone the way of the Dodo.

Reply to
Budd Cochran

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