How do you BLEED the brake line?

viper7mi

viper7mi

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May seem like a easy question:
How do you bleed a brake line?
What kind of brake fluid?

I'm adding a new SS brake line and want to do it right.
Thanks
 
(The only time I have done this on my sled I had the exhaust and chaincase off so I don't know if this needs to be done to access the bleeder screws.)

-First pull the cap off of the reservoir (on the bars) making sure you clean around it first so you don't get any dirt or residue in with your fluid.
-Next find a piece of clear hose (approx. 2') that will fit over the bleeder valves on the brake caliper. (make sure the hose has a small enough inner diameter to make a tight seal)
-Put the other end of the hose in container (cool whip size?) with a small amount of brake fluid in it, keeping the end of the hose submerged in the brake fluid helps it start.
-Next loosen the hex at the base of the bleeder valve a half turn.
-Now making sure you keep the reservoir at least half full the whole time you are doing this pump the brake lever until you no longer see bubbles in your hose...
-Then retighten this bleeder screw and repeat for the other bleeder screw.
-Make sure the little rubber seal on the cap is pushed back in (it shouldn't stick into the res. very far) and put the cap back on and you're done.

-Note the bleeder screws are the nipples covered with rubber caps at the top of the caliper... they kinda look like grease zerts.
-Also it's a pain in the @** to keep such a small reservoir full but if you let it empty you have to start all over so keep an eye on it.
-Finally brake fluid is cheap so don't bother trying to reuse the stuff you drained into
your container.
 
Last edited:
SLEDuluth said:
(The only time I have done this on my sled I had the exhaust and chaincase off so I don't know if this needs to be done to access the bleeder screws.)

-First pull the cap off of the reservoir (on the bars) making sure you clean around it first so you don't get any dirt or residue in with your fluid.
-Next find a piece of clear hose (approx. 2') that will fit over the bleeder valves on the brake caliper. (make sure the hose has a small enough inner diameter to make a tight seal)
-Put the other end of the hose in container (cool whip size?) with a small amount of brake fluid in it, keeping the end of the hose submerged in the brake fluid helps it start.
-Next loosen the hex at the base of the bleeder valve a half turn.
-Now making sure you keep the reservoir at least half full the whole time you are doing this pump the brake lever until you no longer see bubbles in your hose...
-Then retighten this bleeder screw and repeat for the other bleeder screw.
-Make sure the little rubber seal on the cap is pushed back in (it shouldn't stick into the res. very far) and put the cap back on and you're done.

-Note the bleeder screws are the nipples covered with rubber caps at the top of the caliper... they kinda look like grease zerts.
-Also it's a pain in the @** to keep such a small reservoir full but if you let it empty you have to start all over so keep an eye on it.
-Finally brake fluid is cheap so don't bother trying to reuse the stuff you drained into
your container.
Click to expand...

That is a great little write-up, maybe should be in the tech section or FAQ section. I'll throw it in there.
 
Um, you don't want to be pumping the brake lever while the bleed screws are open. This can draw air back into the calliper. Below is how it should be done.

Preparation:
1. Clean and remove reservoir cover.
2. Install clear plastic hoses on each bleed screw.
3. Run hoses into small catch container. This is done because brake fluid makes an excellent paint remover and you don't want that!

Next, Gravity bleed the system:
4. Open both bleeder screws about ½ turn, watch each hose and you should see brake fluid start to run out the tubes. Let this run for a min or two until you don't see any bubbles coming out. WATCH your reservoir, you need to keep topping it up as the level goes down.
5. Once you are satisfied there is no air in the system, close both bleeder screws.

Next, Pressure bleed the system (you'll need two people to do this):
6. NOTE: You can only pressure bleed one piston at a time. Start with the bleed screw closest to the brake line. Get a friend to sit on the machine, so they can work the brake level.
7. Have your friend slowly pump the brake lever 2 times.
8. Next get them to pull it and hold it while you slowly open the bleed screw (remember to do the one closest to the brake line 1st).
9. Watch the clear hose checking for flow and bubbles.
10. When the fluid stops flowing, close the bleed screw, then have your friend release the brake. DO NOT release the lever first as it will such air back into the system.
11. Repeat steps 7-10 ON THE SAME BLEEDER at least 3 times or until you no longer see air coming from the bleed screw.
12. Repeat steps 7-10 using the other bleed screw.

Clean up:
13. Make sure your reservoir is filled to the proper level and reinstall the cover.
14. Wipe up any spilled brake fluid, again it is very proficient at removing paint.

As for what type of brake fluid you require, you'd have to consult your manual.
 
daman said:
The Gravity bleed never worked for me,,had to pump it...
Click to expand...

That can happen, but you still shouldn't pump it with the bleed screws open. When you release the brake level the pressure drops and fluid moves back towards the master cylinder. If the bleed screw is open at that time, fluid and air will be drawn back into the calliper from the bleed hose. You don't want that.

If your machine will not gravity bleeds, skip that section and go straight to pressure bleeding.

No bashing intended...
 
Can't remember how i did mine(was a few seasons ago) if
i had it open or closed, in a car caliper you close it, pump, break, repeat.
 
and you keep the loose end of the hose submerged in the brake fluid it will not pull air in. i perfer the mighty vac type that pulls from the reservoir.
 
This is just my observation, but if you do the inside one first, and then the outside one, it goes faster. JR is right as long as you keep the fule hose on tight, and the end of the hose in fluid it works. Maxdlx
 
pump the same way you do in a car its the same system but smaller ... eatch time u pump the handle just open bleeder and close bleeder before you release brake ...
 
Dot # 4

viper7mi said:
May seem like a easy question:
How do you bleed a brake line?
What kind of brake fluid?

I'm adding a new SS brake line and want to do it right.
Thanks
Click to expand...


Use Dot # 4 brake fluid...
 
gravity feed didn't work at all, that's why I didn't recommend it, keeping the end of the hose in the brake fluid keeps air from being drawn back into the caliper. I have had to pump, close the screw, release, open screw pump... etc. before but not everytime... so I didn't include it.(probably should have) Either way you have a clear tube so you can see what's going on.
 
bleeding brake line

modsrx is right the system is the same as a car so just pump the lever 2 or 3 times and hold it while a buddy cracks open the bleeder. Repeat as necessary
 
Get a mighty-vac pump. It will be the best $30.00 you ever spend. Also, no more dragging the wife out to pump the brake pedal when you change the brakes on your vehicle. Priceless! G.B.
 
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