Lethalv6

I am bringing an 86 iroc back from an 8 yr slumber, I've rebuilt motor/trans and just about everything else including brake hoses and complete drain and flush of the system. Took the car on it maiden voyage yesterday and noticed the pedal still feels spongy. I didn't replace pads because they still had allot of meat on them but I'm now wondering if these things age out just sitting in someone's driveway for so long ? I only got the car up to 30 mph but I stood on the brakes and it just basically eased the car down to a stop. I may be expecting too much too soon, since not driving for so long they may need higher speed to get seated ? Just looking for some advice on what to double check in this system, I bled this thing with a few quarts so I don't think it's air in the lines.
Thanks for any advice.

skinny z

If the brakes were OK when the car was put away and since then you've done a flush and fill, it stands to reason that the system still needs further bleeding.
If that doesn't remedy the situation, it may be that one of caliper pistons has seized in the bore. I've seen where the brake fluid has congealed of the piston outer diameter and won't allow for proper movement. The same can apply to the master cylinder or rear wheel cylinders in a drum brake application.
Rust on the rotors and old pads although taking away from peak performance aren't terribly likely to cause a more or less complete failure as you've described.
But my first guess is air in the system.
I use a pneumatic bleeder which all but guarantees all of the air is removed.

Lethalv6

I bought the car sitting this way so I'm not sure the feel before, this one being my 3rd gen I haven't any comparison but the fluid in the car was quite dark and now is crystal clear..I used speed bleeders and gravity bled before pressure bleeding, I can def try it some more. There doesn't appear any drag when driving so I assume the calipers are locked and I hear no vacuum leaks. I'll keep tinkering.

Tibo

iTrader: (15)

https://www.summitracing.com/parts/m...FY08gQod9L8I7Q

For anyone who does their own brake work a Motive Products Power Bleeder is the best thing you can buy. I've tried many ways (speed bleeders, assistant on the brakes, vacuum pumps) and this is my absolute favorite. Put a quart of brake fluid in it, attach to the master cylinder, pump it up and crack a valve. I've heard of guys opening all four valves and then leaving it for five minutes before coming back tapping on the calipers and leaving another five minutes and then turn it off.