2001 Honda Foreman 450ES
When I pump the lever, brake fluid will not come out. I am assuming this is a problem with the cylinder set inside so I will be replacing this. Would you agree? Also, I can't figure out how to get the cylinder set out. Diagrams show a circlip(c-clip) which holds the cylinder set in, but I can not find it. Your help would be much appreciated. Thanks.

 

Unusual to have to do that on a bike 10 years old, much less 2 years. I would guess something else is going on. Why are you trying to bleed the brakes?

 

This all started because I had no pressure in the brake lever. When I squezed, there was zero pressure. I'm no mechanic, but if no fluid is going out the master cylinder then nothing is getting to the wheels. So, it would appear to me that the cylinder set within the master cylinder is, either,not letting fluid down from the resorvoir or not pushing it out into the line. Like I said, I'm no mechanic, but surely I can fix this. Your response is appreciated and anything further will be a great help.

 

are you blowing fluid?

 

Nothing is coming out of the master cylinder. If I let it set for 5 minutes, I can get a little to spurt out.

 

First off, make sure you have your brakes adjusted properly, it makes bleeding much easier, and if they are not, it's very difficult to tell when they are bled up. Next, take out your bleeder spigots on the calipers and make sure they are not clogged. If you have air in your system up by the banjo bolt fitting on the master cylinder it can be real difficult to bleed out without a vacuum pump (like a mity vac brake bleeder ie.) sucking down by the spigot. Sometimes it helps to use the banjo fitting on the master cylinder as a bleeder valve, but it's a bit messy. If all else fails, you can bench test (or leave it on the machine) the master cylinder by removing the banjo fitting, then put your finger over the hole, fill with fluid and VERY SLOWLY, pump the lever, using your finger to bleed the cylinder. If there's air in your master cylinder you will see tiny bubbles, after several pumps you should notice that the fluid is pushing your finger off the brake line hole when you engage the lever. If it does this there is nothing wrong with the master cylinder. The idea here is to use your finger to simulate the rest of the system. CAUTION, it is possible to squirt brake fluid with enough pressure to hit your ceiling (or get it in your eye) out the relief hole inside the cylinder, if you pump the lever too hard (that is if it bleeds up). So observe this procedure from an angle, not looking directly down at the top of the reservoir.

 

Thank you very much for the detail. I will give this a try tonight(Tues.). You hit on something that I noticed before when pulling the lever. Tiny air bubbles were coming out of the master cylinder, but I did not have my finger over the outlet to try and simulate as you stated. The way I understand this procedure is, if I can feel pressure on my finger and fluid spurts up out of the cylinder then the master cylinder components are ok. The remaining task will be to get the air out of the lines. Thanks again.

 

db, essentially yes that's correct, except you want to avoid squirting the brake fluid out the top of the master cylinder by pumping the lever slow and deliberate.

 

I felt pressure on my finger over the outlet so I guess the master is ok. I assume I need to do this once again then put the hose back on the master. Now, since I have air out of the master will I be able to pump fluild into the lines? Thanks once again.

 

Yup db, if it wants to push your finger off the hole it's good. You might be able to just pump the fluid through, the trx's I've bled brakes on have been cooperative. Fill up the master cylinder and open up both bleeders and wait a minute or two and see if your fluid goes down in the mc, if it does, keep it full and let it go for a while, if not, close off one bleeder and SLOWLY, pump it through until no bubbles show in the fluid. Then do the other bleeder. Make SURE your brakes are adjusted. Sometimes air will set up by the mc, at the banjo bolt fitting. If you're having trouble it may help to bleed it there, slowly loosen the bolt while holding the brake lever the the bar. Wrap a shop rag around it to absorb the fluid, if your careful it's not messy, but it can be if you do things too abruptly. If it's stubborn, really the best way to do it is with a vacuum pump type brake bleeder.