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After parking my jeep Grand Cherokee 1997 for 3 years, I've decided to get it back up and running. My problem is that the brakes are not working. I can pump the pedal but then it looses pressure again. They were working slightly when I pressed the foot down to floor. Any ideas would be great! Could it be seized calipers, ect?

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Check the master cylinder fluid level. If it is low or empty you have a leak. If the reservoir is full the likely cause is a bad master cylinder. To find the leak fill the master cylinder and pump the brake pedal several times. you should see it drip. depending on where the leak is you may have to crawl under the vehicle and look for a wet spot or stain.

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As @mikes stated, you will need to inspect the brakes to see if they are leaking. A good way to do this is to change out the fluid in the system. By bleeding the brakes all the way around, you will be putting fresh fluid into the system and allowing it to work as good as it's going to at this point. Brake fluid should be changed every two years at a minimum, so it's something which is going to need to be done anyway. While you are at each wheel, you'll be in the perfect position to check the validity of each brake component. Look for leaks (obviously). You will also want to check the brake lines to see if there is any bulging. Another common issue is the rotors will have enough surface rust on them where the brakes won't be able to grab. If this is the case, you'll need to either replace these or have them resurfaced. Check the calipers for movement to ensure they are not frozen or stuck. Also, just because you don't find a leak doesn't mean the master cylinder isn't toast. If there were enough moisture in the brake fluid, it could cause corrosion of the seals in the master cylinder, which could allow it to leak down and lose pressure. This would be pretty hard to diagnose, other than what you've described already.

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  • Cheers i have freed off the brakes, discovered that the power boost system behing the master cylinder was leaking underneath, when pumping b4akes it was pouring out maybe this has gone due to the brakes being rusted. New booster orded, fitting next week when it comes. Does anyone know what the small resevior is for just above the master cyliner one. Its says add dot 3 so im assuming that its for the brakes?Also when i have refitted the boost and master cylinder will i have to go to main dealer to have the abs system bled or can i manually bleed it and the brakes be fine. Thanks in advance – Martin Preston Feb 8 '15 at 13:55
  • Assuming you have a clutch/manual transmission, that would be a reservoir for that hydraulic system. It uses brake fluid as well. – Pᴀᴜʟsᴛᴇʀ2 Feb 8 '15 at 16:23
  • Yes i worked that out cheers. Brake pipes need replacing that go to the abs. will this mean that the abs will need to be bled by main dealer or is there a way to do it myself – Martin Preston Feb 9 '15 at 17:11

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