Bleedimg brake questions

[kevino]

I removed the front wheel on my new Ice bear  which has a disc brake. When done with the  wheel  I  filled the reservoir with DOT-3 fluid.    Unbolting the brake fluid tube  had caused it to drain into the dirt.  Now that the wheel is reattached I need to get rid of the air in the brake line.  I followed the method I saw on a u-tube video.  My wife pumped the handle 5 times then held it down while I opened  the drain valve for a moment.   I saw and heard air moving each time I opened the valve.   After half an hour of dong this her wrist is fatigued and never saw any fluid moving through the  line.  Just air.   Also little sign of the fluid  level moving in the reservoir. 

 Any ideas what I'm doing wrong? 

 TIA,

kevino

[aeroxbud]

Did she hold the lever into the bar when you opened the bleed nipple.
You don't need to pump it.
I just undo the nipple slightly. Squeeze the brake slowly. Hold it at the bar, and do up nipple. Repeat, repeat, repeat.
Don't forget to keep the master cylinder topped up. Otherwise you will just suck air in.
It's not good to let the chieftain into the ground. Put a pipe on the nipple. Which then goes into a bottle.

[90GTVert]

If you can't get fluid coming through the line, try gravity bleeding. Fill the reservoir and and open the bleeder. Let gravity do the work for you. Monitor the master cylinder to be sure it doesn't get low on fluid. You should see brake fluid begin to come out of the bleeder, but it may take a few. Once you see fluid coming out, close the bleeder and you can continue the regular brake bleeding process as you were trying before.

Here's another tip, in case you can't get a really firm lever feel even after the regular bleeding process. Make sure the reservoir is filled. Secure the cap on the reservoir, just like you're finished with the job. Zip tie or bungee strap the lever to the handlebar, as if you were pulling it to brake. Then don't touch it, at least overnight. Sometimes this will get a nice firm lever feel when other methods fail. Take a look at your fluid level window to be sure you don't need to add any more before you call it done.

[kevino]

Okay the brake handle is taped open, the bleeder valve is loose and the reservoir is full. I don't see any fluid moving.

[df41590]

You can also try taking the handle of a screwdriver and lightly tap on the master cylinder. Sometimes an air bubble can form inside and prevent fluid from flowing.

[kevino]

Tried it, nothing happening.

[aeroxbud]

Very occasionally if I have changed brake pipes. You might find it will not bleed by the usual methods.
If you reverse bleed it, you force fluid in under pressure from the bottom. It will work. You will need to get a big syringe to do this though.

[kevino]

I watched the video. Seems too simple to work. But I've got syringes and tubing so I'll give it a try.

Thanks,

kevino

[aeroxbud]

The bigger syringe you have, the easier it is.

[pinkscoot]

I think your getting it backwards. Fluid will only leave the reservoir when the brake handle is being pull and it pumps the fluid down to the caliper. When the handle is all the way against the bar the valve is closed so no fluid will flow. So open the valve pull the handle, hold it against the bar and close. When you have pressure all is good. If you think there may still be air then do what Brent said. But of course because you do have some pressure the handle won't be against the bar. Or get one of these and make it easy. This is all assuming the brakes worked before you started and the brake line isn't clogged.

[FrankenMech]

Oct 25, 2020 17:51:37 GMT -5 pinkscoot said:

Or get one of these and make it easy.

Nice bleeder!

[pinkscoot]

I love it. Almost all of my brakes are nice and tight. When the oil tank had drained into the crankcase on the TGB out it came to suck it out. For $34 it is a good multifunction tool.

[kevino]

Gerry-rigging with a 12cc syringe and clear plastic tubing I pumped fluid in from the bottom. The lever is still spongy but not bad. Problem now is I lost one of the two philiips holding the starter button on. I tried using #4 metric bolts but mine are too long. More Gerry-rigging to come.

kevino

[aeroxbud]

Thread a couple of nuts on. Then cut down to size. When you undo the nuts, it cleans the thread up.
Now you have fluid in there it should be easy to bleed the air out.
You could try tying the lever back to the bar overnight. The air might work it's way out. You don't need a lot of pressure on the lever, just enough so the piston is open.

[kevino]

This morning the brake lever is still mushy but not much worse than the other non-disc brake. But all the brake bleeding caused one of the starter button screws to fall out, somewhere under ankle-high fallen leaves. The closest replacement I Could find at the hardware store is fine-thread metric #4. Maybe cutting one down will work.