Do you use a section of clear silicone hose over the nipple to watch for air bubbles? And if so what size would it be to bleed a set of 4pots

Thanks in advance

 

You can't see the air bubbles properly, the best method is to lead the hose into a clear jar contining about 30mm of brake fluid. THEN you can see bubbles or not.

Diameter is about 6mm i'd.

 

Get yourself a brake bleeding kit, there about £15 and make the whole job a piece of ****!!
Think halfrauds sell a Gunson one.

 

was looking at the brake bleeding kit but didn't know if they are any good? How can you see if there's no air or its fresh fluid if you'd ure in the car pressing the brake pedal?

 

It's a 2 man job really that way.

The Gunson ones run off your spare wheel so make it easier if your doing it on your own

 

Also read those kits can allow some air back in so unsure on if to bother getting one if its still a two man job

 

With the kit you get a nozel which attaches to your spare wheel, this then connects to a sort of header tank full of brake fluid, this then connects to your brake fluid reservoir. When you open the vale at the spare tyre end this fills the brake system with fluid under pressure. All you do is go round each caliper one at a time and open the bleed nipple and allow the old fluid to be forced out under pressure, use a tube to direct it into a catch tank. I went round twice just to be sure, also make sure the header tank doesn't run empty!

 

I've read on here that those systems don't work very well on the classic impreza reservoir tank?

 

i have never got the gunson to work on my newage brake reservoir.
Had to drill a hole in the reservoir cap as the ones in the gunson kit dont fit. And then the system isn't air tight on the subaru so it just sucks all the fluid in and then pushes it out through the cap.
2 man job every time for me.

 

How about a length of pipe long enough to reach from the bleed nipple to the brake reservoir? Once the nipple is cracked open it will just refill the reservoir whilst you are free to pump the brakes?.

 

Interesting idea, wonder if it would work?

 

Funnily enough i'm just about to go out and bleed my brakes, but i doubt i have hose long enough to go from rear caliper to reservoir.

 

plus by the time the fluid has travelled all the way along the hose the reservoir would be nearly empty.

 

You can also get a kit that has a one way valve so when bleeding you don't have to keep closing the bleed nipple as the fluid can't travel back into the caliper.

Have used this on the bike but not tried it on the car yet.

 

I use one of these kit's, superb for 1 man job. 1 tip is to grease or vaseline all the way around the nipple threads as this prevents air been sucked back in through the cracked off nipple. Then just wipe it off after you have finished bleeding and tightened the nipple back up.

 

Of course but you'd account for that.
So you'd link the hose from nipple to reservoir, crack it open and fill the reservoir. Then pump brake, keep an eye on level until the fluid comes through the pipe into the reservoir. All you'd do once your happy all the air is out is tighten up the nipple and pull the pipe off over a container.

I've just done mine. All i did was have a small pipe into an old takeaway container, cracked the nipple and started to watch it drip. The level in the reservoir barely moves until you pump the brakes, so i just kept topping up, pumping the brakes and repeated on all 4.

I didn't have a hose long enough to try the other idea.

 

You don't want the old fluid back. It's hygroscopic, (absorbs water) so deteriorates over time anyway.

New fluid isn't expensive enough to warrant saving the old. Not in the context of owning a Scoob, anyway

 

The correct way of bleeding is to replace the whole contents of the braking system with new fresh fluid. Never recycle old fluid and never drain the system. (clamp/block flexi hoses if parts need to be disconnected)

I usually work on feel, and bleed at least 250ml of fluid out per corner. With a few pumps on the brake pedal with the bleed valves CLOSED to asses pedal feel (engine off) to ensure its rock solid.

If the reservoir ever runs dry...start again!


Also its not just bubbles you are watching for...its also fluid colour.

 

The issue I've seen with some of these is they have to be opened via loosening the bleed valve in the caliper thread.

The problem here is when releasing the brake pedal, air can be sucked back though the threads of the bleed valve.

If you ever use a vacuum bleeder you can cleary see it sucking air through the bleed valve threads.

 

Of course you wouldn't want to re-use the old fluid that goes without saying.
Vaccuum bleeders are good if you have a compressor, but i've known them to not be the solution in the past.

There's nothing like using the braking system under its own steam to push fluid through and therefore air out.

 

A quick tip,

Bleed nipple open
Fit the bleed hose into a bottle
Press brake pedal 8 times job done,

I do this on mine and works perfectly

Although I can't be held responsible if u do it wrong, just make sure the resovoir is always full while doing it, or get a mate to help

 

Do you depress the peddle with the reservoir cap off or keep replacing it after topping up with fluid?

 

I've always left it off to allow the air bubbles to escape once hitting the top. Only pump the brakes 2 or 3 times then check the level, top up and repeat.

 

Will air not get sucked into the system if you release the depressed brake pedal while the bleed nipple is open? I have always done it by getting a mate to open bleed nipple , I depress pedal , they tighten the nipple then I release the pedal?

 

If the bleed nipple is open and the pipe connected to it is in about 30mm of fluid then in theory the only thing to get sucked through will be brake fluid from the reservoir. That is of course if you have plenty of fluid in the reservoir. If you depress the pedal you will notice a significant drop in fluid in the reservoir where it is being sucked in and back out the nipple/pipe.

 

No air gets sucked in cus the bleed pipe is in some fluid in the bottle sorry I forgot to mention that, but getting a mate to help is just as easy

 

Air gets sucked in through the thread of the actual bleed nipple itself.

Thats why it needs to be fully closed whenever the brake pedal is released.

 

^ yeah that was my understanding too, plus I notice that's how ed china does it too ( so it must be right haha)