Fluid holes at bottom of MC Reservior and soft brake lever

What is the function of the small hole in the bottom of the MC reservior? I rebuilt my MC and had the cover off and pulled the brake lever but nothing happened with the small hole in the bottom of the reservior. Should fluid squirt out or should I be able to see anything happen at all?

 

Re: Fluid holes in the bottom of the MC Reservior

It serves to release pressure and allow the pads to release back when you let off pressure on the brake handle. It MUST be clear for proper brake operation, otherwise you will have a sticking caliper with dragging brake pads and associated heat.

 

Re: Fluid holes in the bottom of the MC Reservior

If i remember correct, should have 2 holes(one is so miniscule it is easily clogged) the large one draws fluid down into the sytem when the plunger is pressed, and the smaller one lets the fluid return when released. it shouldn't spurt out, but there should be some action going on there which may or may not be visible. Thats the way it was explained to me, if i have this wrong would someone please correct me.

 

Re: Fluid holes in the bottom of the MC Reservior

When I rebuilt the MC I cleared the little hole and I have it all back together. When I pull the brake lever the first time nothing happens, the wheel doesn't stop, if I spin it a second time and pull the lever it stops immediately. Could this little hole be the problem or could ther ebe something else I need to be looking at?

 

Re: Fluid holes in the bottom of the MC Reservior

Sounds like you still need to bleed the brakes.

 

Re: Fluid holes in the bottom of the MC Reservior

I just bled the brakes some more and no bubbles appear to be coming out, I even tapped on both calipers and all metal fittings to see any bubbles are logged. So this is where I'm at, at first pull the brake lever it is soft (bottoms out to the throttle) after a few squeezes of the lever it gets firmer. How do I know if bleeding more will do the trick? I used a little one-man bleeded that has the clear hose going into a small plastic bottle with the air vent on top. About to give up. Please any ideas?

 

It could well be that you are experiencing bleeding past your main piston seal. When you rebuilt, did you lubricate your internal parts before assembly? If not, you might have had the piston seal drag and the lip flip over. There have been numerous times that I have had to wait a day or two to complete bleeding because of air bubbles trapped in the lines. Leave it overnight or a few days if you can and try to bleed it anew. Another thought is to the condition of the rubber brake lines. I don't think this is the bulk of your problems but it can contribute to the overall problem. Shuck those old lines for new braided stainless, you will find a whole new brake system is hiding in there.