I have a rusted out rear left brake line on my 1997 blazer. Is there a replacement and how difficult a job is it?

No reset on 98"s bleed all the lines. Replace all the lines in my opinion...That's what I do. we are talking almost 15 years of rust and fatigue...

brakes are a critical safety issue
the flares on the lines are double flairs ( required by law)
it would be cheaper in the long run for you to go to accredited brake and clutch professional shops and get quotes to replace the steel lines
they have the equipment , material and the knowledge to do the job properly
or you can diy by going to a wrecker/junk yard that handles your make of vehicle and get good rust lines as replacements

I will try to inform you about the rear brakes. Depending on trim level, the higher end vehicles have rear rotors. This means that the Emergency brakes are contained inside the rear rotor housings and are actually drum brakes

You will have to see a pair of these linings to understand what is possible with these units. The E-brake drums will severely pit and rust unless used regularly. The E-brake shoe material often detaches from the metal housing and is in no way as thick as regular service linings.

Frozen cables are another possibility. Or the E-brakes are compromised and there is no brake material left on the shoe.

This particular job is best left to a Brake shop. It is more difficult than changing oil, installing a muffler or starter, and on par with Ball joint repair.

Please comment on my info.

you most likely have a brake line rusted threw, cut the line ahead of the leak and after the leak and splice in a new piece of brake line, it will have to be steel, you can not use rubber. if you take the line to a parts store they can size it up and get you a piece of steel line and some pressure fittings to put it back together, after you repair the line then you will need to bleed the rear brakes.

Did you remember to bleed the master cylinder itself? When the master cylinder runs dry you should start bleeding your brake system at the master cylinder and then continue on to each of the four wheel cylinders.

No you need the make a new one. The best way is to buy a coupler napa sells them. The line rusted out in a spot ware you can't even see it but i know. You will need some speical tools a tubeing cutter a torch propane is fine and a flareing tool. The coupler needs to be three feet long it will have flared ends and fittings on it. You must remove the fitting that attaches to the end of the brake line at the rear fitting unscrew this is what you need the torch for. Hit it for 30 secounds with heat and spray with wd 40 it will break loose. Then screw the new line in the fitting you don't need to tighten all the way then carefuly snake the line back over the axle don't crimp the line use something round and slowly shape it . Then cut the old line with the tubeing cutter toward the front of the vehicle you need a stright cut but make sure that the coupler is long enough to reach to cut, Then you need the flareing tool to flare the end you just cut off don't try to dubble flare single is fine.But before you flare this end you need to slide a fitting on because after its flared it woun't go over the new flare. Then you just screw everything in place and tighten. Then bleed the brakes a lot of times you can just bleed the rear drivers side cylinder then check the master cylinder resiovier for fluid level

Since the brake line is under high pressure when the brakes are applied,patching the line is not possible,but the brake line comes in many different sections so you would only need to replace the bad section.

This could be very difficult due to access and being able replace line from its 2 union points. you will have to purchase stright brake lines and bend to fit then bleed the brake system

You have a raptured brake line. Mostly from rust. Everytime you apply pressure to the brake pedal that is why its taking brake fluid. Keep adding brake fluid to your master cylinder-don't let it go dry or you will lose all of your back brakes if you didn't already. You have to have your brake lines replaced and have your brakes bled. Should be about a $100 job at a good brake shop.

Brake lines are not expensive, you can purchase different diameters, and lengths at any parts store. If the line is rusted and leaking, the rest of the brake line system needs to be visually inspected, as usually when a line rusts through, the rest of the system is probably rusting away and may also need replacement.
So, although the parts are not expensive, this is a lousy labor intensive job. The lines will be rusted at connections and difficult to separate, and brake system will have to be bled to remove all air. Your safety is of the utmost importance, so get this fixed before you drive it. To fix the one line should not cost much, to replace all the brake lines could cost several hundred $. If you can do it yourself, you can save a lot, but as I said, it's a lousy job, especially if you don' have a lift to raise the car for easier access. Good luck.