Do I need to flush brake lines?

I didn't see this question when I searched the forum, so here goes: I have an 85 Maxim that has been sitting, garage kept for 10 years. I'm finally getting around to getting it running again. The brake fluid level is fine, the brakes aren't mushy, and the master cylinder cover has never been removed. It is necessary for me to flush and refill the lines?

 

I would - brakes are an important item. Won't be too hard and worth the effort.

 

Brake line need flushing periodically. for me its every two years. Brake fluid goes rancid after a while as well as gather moisture especially in the small resevoirs we have in these bikes,

 

ABSOLUTELY. Mine was so bad (and the PO was RIDING IT) that I used my shop vac to suck all the YUCK out rather than pump it thru the system. My cover was so corroded I replaced it. You'll want a new gasket at the very least...

 

Yep - You will want to take apart all compnents and flush the system. You will be surprised at the amount of brown goo you find in there, which is congealed brake fluid. My brakes worked fine, and there were no external leaks, but the amount of brown "snot" in the system was a real surprise. Take the time to do it right and make sure that your brakes can be depended upon with your life each and every time, which is what they really do when you come to think about it.

 

I didn't flush mine after the 8 yrs of sitting but, I had cleaned the gunk out of the master cylinder and thought that that would be good enough. Guess what? My caliper started to stick after a day or two of use. I Ended up taking the caliper apart and finding a lot of nasty stuff behind the piston. I also, with RickCoMatic's help, found that there was a lot of hard junk behind the seal in the caliper that had to get removed.

From my experiance I would flush the system and clean behind the seal in the caliper, just becareful not to scratch the bore.

 

For what it costs to do the whole job, including buying a One-way Valve Bleeder, you can't buy better insurance for staying away from Brake trouble.

Get a couple of cans of Disc Brake Kleen
The One-man Bleeder
A can of fresh DOT-3 ... and give it a Flush and Clean.

Pull the Master Cover and Seal
Pull the seal away from the Master.
Clean the underside of the Cover.
Both sides of the seal. (Expand it if necessary)

Suck the old Fluid out of the Master with an Ear Syringe
Spray the inside of the Master and the sight window.
Evacuate the cleaner with the syringe.
Dry it all out with a Kleenex.

Put a little bit of New Fluid in the Master ... below half.
Pull the Brake Bleed Nipple off the Caliper and wrap it with Teflon Tape.
Pierce the tape at the hole in the Bleed Nipple.
Stick the Bleed Nipple back in.

Attach the Bleed tool.
Fill the Master 3/4's full.
Make sure the Bleed Nipple is open for bleeding

Pump the fresh Brake Fluid through the system until what is coming out is as clean as what you add to the Master to keep the level above half while you are flushing.

Once you have clean fluid throughout the system
Close the Bleed Nipple and Pump-up the Brakes.
Have somebody help you with the brake lever.

Pull the brake lever while releasing the pressure at the bleeder.
Pump-up and pull the lever tight to the handlebars two or three times (or how ever many time it takes to evacuate air bubbles) and you have a fresh and cleaned braking system!

 

Wow! Thanks for all the quick replies and advice, esp. the step-by-step procedures. I'll let you know how it turns out...