Power steering fluid / brake problems

Let me start by saying i am a car noob. My grandpa bought me my first car a couple of months ago, a 1977 buick Lesabre. I've noticed two problems going on lately. The first is the power steering fluid. It burns right through it and i have to add more every month it seems like. The 2nd is a bit more important, the brakes are loosing pressure. I added more brake fluid and pumped them up, they loose all pressure within seconds. I explained the problem to my grandpa (a mechanic) and he said the maser cylinder sounds like it needs to be replaced. there is a small puddle under the car directly to the left (passenger side) of the master cylinder. I was told that is not brake fluid, although the liquid appears to be transparent. it looks though like it hasn't leaked the a couple of days though because it is drying up. How do i replace the master cylinder? and about how much should one cost?

It's a good bet that your '77 LeSabre likely doesn't have antilock brakes (it was extremely rare in the '70s). Changing the master cylinder is fairly easy, but the entire system will have to be bled afterward. Loosening brake bleeder screws on a 34 year old car will require patience, good penetrating oil, the right tools, and some luck. Once the bleeders have been freed and can be operated, the system can be bled.

You will need a six-point bleeder wrench with probably 5-16" and 3/8" ends. You will need a line fitting wrench (flare nut wrench) with probably 7/16" and 1/2" ends. You will also need some threaded fittings and hose barbs with tubing to bench bleed the master cylinder before installing it.

A remanufactured MC for that should probably cost about $30. A master cylinder, a quart of brake fluid, and an assistant to bleed the brakes should be all that is necessary. Having a little bit of lithium grease to dab on the tip of the plunger for the master cylinder will also be a good idea.