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Speaking to a mechanic friend a few years ago he told me that the best way to bleed hydraulic lines like brakes and clutches was to use a vacuum, apparently pumping the peddle can cause all sorts of damage to your brake booster diaphram and possibly the piston and bore of your master cylinders, and pressurising the resevoir needs a lot of different adapters and has been known to blow seals.

So on and off for years I've been trying to figure out a cheap simple way to make a vacuum pump for this task, it came to me the other day and I could have slapped myself for not thinking of it sooner.

Ingredients:
Standard $2 spray bottle
Length of fish tank tubing
Tubing joiner

Using this gear create this device:


Then all you need to do is push the tubing over the bleed nipple, unlock it and bleed your brakes, clutch, whatever, I used the bottle that goes with the trigger to squirt the fluid into, didn't want to spray brake fluid everywhere.

Brilliant!

Now patient it, and sell it as the "BYB Bleeder".... then we can share the profits

yeah awsome!..... i'm sure my old master cylinder sh*t itself after too much pumping during various brake system alterations. and the best thing is no pumping assistant required

timmo

Matatak wrote:well it is a good idea alot simpler than the usual way which people seem to have problems with for some reason dunno why.

but i will never beleive tthat bleeding brakes can do damage to the booster or Master cylinder.

Yes, good idea.

"Junk" within the bottom of the master cylinders' travel is what usually causes master cylinder failure.
Half pedal travel is the best way of avoiding M/Cylinder internal leakage failure.
And of course, any form of fluid flow out of the bleeder nipples without moving the pedal is a better way still.

Top stuff Jordan!

Hah! - How good is that. Cheap & Brilliant.

Beers on me when I come down to Coffs at the end of the month for the Brumbys maiden Road Trip!

Good on you for sharing it.

Mate have you heard of the show 'The New Inventers' on the ABC... wink, wink, nudge, nudge haha.

Now wait on.. you could think up a few more uses for this device and then sell it on late night TV before someone copies you...let them waste time and money on the patent!

There is a warning in the factory manuals about when removing booster that the rod does not drop or the booster is rendered useless. This may be able to occur when bleeding ?

The Canyon (looks like you have one) brand squirters are the most durable. Do you include care instructions ? BF is pretty harsh on some stuff, do you wash out with water after use ? or frow it away ?

and the other advantage is it'll only take one person to operate, no more getting a mate to pump the pedal while your under there waiting for the bubbles to stop, this invention has come at perfect timing, i was dreading having to bleed all the brakes on the b4, through the abs and all (is there any tricks for bleeding them through the abs or just do it as normal?)

BRILLIANT!!!!!!!!!!!!!!!

steptoe wrote: There is a warning in the factory manuals about when removing booster that the rod does not drop or the booster is rendered useless. This may be able to occur when bleeding ?

The master cylinder doesn't move using this process.
So no risk of internal damage.

The way I bleed my brakes is to get some tube like Jordan has, attach the tube to the bleeder nipple and put the other end into a container. Then you can just push the pedal yourself, because of the tube no air is sucked back into the system.

To do the ABS there is a special mode you have to put the car into to open the cylinders inside the abs unit. Consult the service manual

1) I like this idea

2) How does the spray head allow chunky stuff if in the fluid (if present for some reason) to pass through?

3)

BaronVonChickenPants wrote:...apparently pumping the peddle can cause all sorts of damage to your brake booster diaphram and possibly the piston and bore of your master cylinders

So I should just use my handbrake for braking now?

Mate have you heard of the show 'The New Inventers' on the ABC... wink, wink, nudge, nudge haha.

Now wait on.. you could think up a few more uses for this device and then sell it on late night TV before someone copies you...let them waste time and money on the patent!

The mechanic that I spoke too actually had a commercially available hand operated vacuum pump that captured the fluid into a chamber, came complete with pantent, but I couldn't justify the ~$150 for the odd occaision that I need to bleed something hydraulic.

The Canyon (looks like you have one) brand squirters are the most durable. Do you include care instructions ? BF is pretty harsh on some stuff, do you wash out with water after use ? or frow it away ?

I have no idea what brand it is, just tripped over it in the laundry and had a "light bulb moment." I washed it out with water when I was done but more so it didn't leak fluid in the back of the car rather than for it's own protection.

"Junk" within the bottom of the master cylinders' travel is what usually causes master cylinder failure.
Half pedal travel is the best way of avoiding M/Cylinder internal leakage failure.

So I should just use my handbrake for braking now?

but i will never beleive tthat bleeding brakes can do damage to the booster or Master cylinder.

So I am told the damage to the diaphragm is caused by pushing the peddle all the way to the floor, which extends it beyond it's natural position, particularly a problem for old cars where the diaphragm doesn't have the flex it used to.

The problem with the master cylinder is if there is a ridge worn in the bore it can destroy the piston seals and as littlewhiteute said, a build up of crud in the bottom of the bore won't help either.

How does the spray head allow chunky stuff if in the fluid (if present for some reason) to pass through?

So far I haven't had any issues with chunks, but you can remove the fine nozzle from the front of the trigger for cleaning, maybe even leave it out all together.

If you wanted you could screw a couple of fittings into the top of a jam jar or similar air tight container and have it as a capture chamber but the trigger is much more effective at moving fluid than air.

And cheers, glad I could help.

Jordan.

BaronVonChickenPants wrote:The problem with the master cylinder is if there is a ridge worn in the bore it can destroy the piston seals and as littlewhiteute said, a build up of crud in the bottom of the bore won't help either.

That's easily prevented: when you use the brakes, push the pedal all the way to the floor, Problem solved! :-D

wow that is a brilliant idea!
I'd be extremely careful to adjust the nozzel to be a thin stream rather than a mist spray, it would be very hazardous to breath this in! Better yet perhaps seal some kind of chamber or bottle around the end of the nozzel.

A1 from me. You are the man.

hahaha thats great! cheers for sharing
im gonna give it a go now, not that i need to just for fun

Matatak wrote: any1 still thinks pushing the pedal to the floor can do damage is wrong. ill never beleive it (ever) if ur master cylinder is gonna go when u bleed the brakes coz its 'worn' then u probly dont want to drive with it as it culd jsut as easily screw up on the road.

Mate, I've been a mechanic a little bit longer than yourself, you'll also see others have agreed with what I said about applying full stroke to master cylinders that have seen some service.
Any cylinder will eventually fail, but full stroking a cylinder that's been in service for a while WILL damage the cups, then you WILL have early failure.

Same goes for replacing rear brake linings, you should replace the wheel cylinders at the same time, because the old existing cylinders will now start to leak after the linings have been replaced.

Matatak wrote:my boss disagrees with u aswell no offence meant and i aint tryna start an argument.

That's ok, ,we all have own theories, it's just I've seen too many fail not long after having calipers or wheel cylinders replaced.
A sinking pedal while stationary is the first sign.

Suparoo wrote:Brilliant!

Now patient it, and sell it as the "BYB Bleeder".... then we can share the profits

Nice one Suparoo! He does all the thinking, we do all the profit taking... Thats about how it goes in the real world isn't it?

Good effort BVCP, I need to replace my rear brake cylinders but don't have time to do them when someone else's around, this will make things a lot easier!

Cheers

Bennie