bleeding brakes!!!?

Question

I have tried unsuccsessfully to bleed the front single disc brake on a Suzuki 400 twin. I have replaced the caliper piston, seals etc. also the master cylinder piston, seals etc. with genuine Suzuki parts but am totally unable to get any brake fluid through , I think I've tried every trick in the book, unless you know differently! ( I hope !)

Answer 1

1st of all always remember air rises therefore start at the top at the master cylinder there are two holes in your master cyl. one large hole and one small hole the small hole is about the size of a very thin wire like you'd find on a wire brush if that is clogged then it will be impossible to get good pressure.If the hole is clear then try this trick take some visegrips and gently crimp off the brake line near the master cyl. pump the lever then crack open the bolt that secures the hose to the master cyl. do this till you get full pressure to the lever it'll almost feel like the lever is stuck. Once you get full pressure there then move to the caliper, heres what you need to do get a peice of hose(clear) that fits snuggly onto the bleeder then in the other end put a bolt that fits snuggly as well take a razor blade and make a small cut (about 1/4 of an inch) in the part of the hose that has the bolt in it right along the bolt then get an empty coke can bend the tab over the mouth of the can then insert the end of the hose that has the bolt in it into the can and pour a little brake fluid into the can just enough to cover the bolt this will allow air and fluid out but nothing in ( this is called a one man bleed kit Homemade that is) put the hose over the bleeder on the caliper then release the vise grip from the top at thew same time applying pressure to the lever forcing the fluid down then open the bleeder and leave the bleeder open and just pump it, keeping the resevoir full until you cant see anymore air bubbles come through the line at the bottom. then close the bleeder and then your brakes should be working.Be sure and get the front wheel off the ground and spin it to be sure that the brakes arent dragging until you apply pressure to the handle.

Answer 2

The fact that you have replaced the seals within the cylinder & caliper leads me to the possibility thay there may be a component seal incorrectly fitted

Normally the fluid will gravity feed through the system as the master cylinder is higher than the caliper and forcing fluid through with application of the lever merely makes the job that much easier.

If you are using a tube and bottle then I apologise for going through the process

Fill the master cylinder with fresh fluid. Put about 10mm of fluid in a clean dry milk bottle. Place a good fitting rubber tube over the end of the bleed nipple. Open the nipple about half a turn and with the other end of the tube in the fluid in the bottle gently apply and release the brake lever. Continue topping up the master cylinder and continue with the lever applications until no more air bubbles appear to be coming out in the bottle. Tighten the bleed nipple and you then should have a good brake. If you haven't the I really suggest that something has been put back incorrectly.

Now that said if you still have problems then I would suggest that you seek some professional help. Remembering that this is your brakes here and you will be really pi$$ed if they don't work when you most need them

Good Luck

Answer 3

Had this on a Suzuki, Take out calliper pistons pour in some brake fluid refit pistons and squeeze callipers back in right to the stops with a G cramp.This will push brake fluid back towards the master cylinder and drive the air upwards and out of the system. use a turkey baster to take out any excess fluid from the master cylinder so that it doesn't over flow.leave the Clamps in place ,bleed through calliper as per normal remove clamps refit callipers pads to bike and pump pistons out remembering to re fill fluid as you go.

Answer 4

I have found in the past that if you put an elastic band or cable tie around your handle bar to pull in your brake lever (with a full resevoir) and leave it like that all night you should get all the air out.
or get a big syringe connect to the bleed nipple at the calliper and rervse bleed the system making sure you close the nipple if you need to refill the syringe to keep air out. Hope this helps.

Answer 5

slack of the blied niple on the caliper, push clear plastic tube over ant suck. if nothing com then master cylinder asembled wrong.
or hose collapse insides. If Nothing com undo pipe from Master cilinder, fluid should leak out, if it do slack bottiom end, if fluid leak then it must be Caliper but not likely.
If all ok fill master cilinder wit Break Fluid, Dot 4 or 5, som pilloks uses Hydraulic fluid which swell seals and wrek system, undo caliper blid screw and haf coffee, top up master cyl efery cupel off minit. den tighten blid screw, Squeeze break lever and undo blid screw, wen lever al way bak tighten agen, Break then shud work OK.

Answer 6

Like RUDOLF M said, you have to bleed the master cylinder.
--Cover all painted parts on your bike (a plastic shower curtain works). Brake fluid disolves paint.
--Where the brake hose bolts to the master cyl. - wrap around with a rag, to further protect from brake fluid getting on stuff.
--Unbolt the brake hose and remove from master cyl.
--Block the hole on the master cyl. with your finger.
--Pump the brake lever, hold, move your finger to let the air out. Repeate until no more air comes out.
--Keep the lever pressed slightly.
--Have the bolt and hose ready and install/tighten as fast as you can to prevent air from going in.

--The same procedure you use to bleed the brakes at the bleeder valve on the caliper - bleed at the bolt & hose at the master cyl.
--Then bleed at the bolt on the caliper.
--Then again at the bleeder valve.
--Last resort - remove the master cyl cover. Continuously squeese the lever a tincy bit (careful - to much and to fast, brake fluid will squirt up in the air). Watch for air bubbles coming into the master cyl. - continue until they stop.
--Use "acetone" immediatley, to clean up any spilled brake fluid.

Answer 7

If you have install part properly.....
First
- top your brake reservior and leave the cover open
-loose the brake bleeding point nut
-start pump your brake lever until you see the fluid is out....
-slowly tight the nut and press the brake lever
-top the level and close the cover.
- and pump the brake until you have the pressure.

If no fluid out from the bleeding point.Replace the hose

Answer 8

Bleed the master cylinder at the output port then check the line for kinks, if u have fluid going into the line but no fluid out it might be clogged with debris, change it

Answer 9

Make sure That you have fitted the cup seals the right way round,for it looks like the fluid is by passing th seals

Answer 10

There may be an airlock in the master cylinder, you either need to pressurise the reservoir or suck it through. If you do decide suctions the way to go I'd use a syringe as brake fluid tastes bloody awful.