93 Accord brake system problem

Car has 150K miles. Was having issues with brake pedal gradually creeping to floor so I replaced master cylinder with aftermarket one. Bled brake lines on each wheel but problem didn't go away. I thought maybe fluid was bad, so I continued bleeding until 2 quarts of new fluid in system. Old fluid was dark/carmel colored. This worked for about 2 weeks. Now the brake pedal goes fairly quickly to the floor and now not safe to drive. When engine is off and brake pedal depressed, can still push it to the floor. Is my new master cylinder faulty?

I have a 95 Accord that had a similar problem. For a while, my pedal would have to be pressed down all the way in order to stop. I had my master cylinder replaced but it kept happening. The shop didn't know why. I then took it over to Meineke (who specialized in brakes) and it turned out that one of my calipers was missing a pin and was not working. After they replaced the pin, my pedals were solid. I had them clean the caliper sliding bolts as well. I have no problems now. Hope this helps.

Did you bench bleed you master cyllinder before installing it?

I have heard that old hoses may just swell. Check it out as well.

Good luck,

Sam

No, I didn't bench bleed the cylinder. How do I do that now, with it installed? Explain "bench bleed" please. Thanks.

I have never done it on Accords... I think Honda's master cyllinder is a bit different. So I dis a search...
Read these threads:
http://www.automotiveforums.com/vbulletin/showthread.php?t=635467&highlight=bench (http://www.automotiveforums.com/vbulletin/showthread.php?t=635467&highlight=bench)

http://www.automotiveforums.com/vbulletin/showthread.php?t=457379&highlight=bench (http://www.automotiveforums.com/vbulletin/showthread.php?t=457379&highlight=bench)

Took old cylinder off, took apart and cleaned, reassembled, bench bled it......still didn't work. Bought new one and bench bled it this time and everything works fine. Thanks for the help everyone.

Took old cylinder off, took apart and cleaned, reassembled, bench bled it......still didn't work. Bought new one and bench bled it this time and everything works fine. Thanks for the help everyone.
Thanks for update! I am glad it works!!!

In your first post you said you used aftermarket MC.

What did you use now?

Sam

Assume it was an aftermarket. Bought from Autozone as it was 1/4 of cost of OEM. First one bought off internet :banghead:

Master cylinders are not rocket science type devices. The reason a master creeps to the floor is that the cylinder is scored or the rubber cups are worn out. If a rebuilt one doesn't work means it wasn't rebuilt properly. I would never buy one off the internet unless I rebuilt it myself before installation.

Good for you. These were brand new master cylinders, not rebuilt ones.