Vacuum brake bleeding

TeGGer=AE wrote:
> Nate Nagel > floridly penned in
> :
>
>
> >
> > I've found that on older cars using the pedal-pump method is a good
> > way to end up replacing the MC. Unless it's been meticulously
> > maintained the inside of the MC will be rusty outside the normal
> > travel area of the piston, and wiping the seals over rust will
trash
> > them.
>
>
>
> Agreed. But I've found that even in cars where the fluid's never been

> changed, you're OK with the pedal-push as long as the car is less
than
> roughly 7 or 8 years old. It's over that when the neglect really
seems to
> take its toll.
>
> If the fluid's been changed annually since new using the pedal-push
method,
> the MC will the life of the car.
>

Less than 7 or 8 years old? I don't think I've ever owned a car that
new! (one exception, a car that I bought new, but I other than that I
can't remember ever having a car less than 15 years old...)

nate

Ted Mittelstaedt wrote:
>
> They don't work - I have an A/C vacuum and I've tried different vacuum
> levels with various Rube Goldberg contraptions on the bleed screws.
>
> Other than a pressure bleeder, the next best thing is an assistant sitting
> in the car pressing the brake petal while you have the bleed screw open.
> I usually use my wife for this when I do our vehicles and the procedure
> works well except for a rather annoying whining noise. (from the
> wife, not the car ;-)
>
> Ted
>
try out speed bleeders. One man brake bleeding, no special tools
required. Loosen bleeder, attach hose into jar, pump pedal. Done.

Ok, so I still do it two person so I can watch the fluid come out, but
it's definitely quicker and less work.

Ray

"ray" > wrote in message
...
> Ted Mittelstaedt wrote:
> >
> >
> try out speed bleeders. One man brake bleeding, no special tools
> required. Loosen bleeder, attach hose into jar, pump pedal. Done.
>

I already tried those, a waste of money. The slightest amount of brake
fluid contamination will clog the valve with grit, then the pressure builds
up and blows the hose right off the bleed screw. If you want to pay
the shipping for the last one of those I bought and try to unclog it you
can have it for free.

The other problem is the positioning of the bleed screws, never in a
good area for attaching a rubber hose to them. not to mention that
fluid not only comes out the screw hole but all around the threads of
the screw, so you never catch it all.

Ted

Ted Mittelstaedt wrote:

> "ray" > wrote in message
> ...
>
>>Ted Mittelstaedt wrote:
>>
>>>
>>try out speed bleeders. One man brake bleeding, no special tools
>>required. Loosen bleeder, attach hose into jar, pump pedal. Done.
>>
>
>
> I already tried those, a waste of money. The slightest amount of brake
> fluid contamination will clog the valve with grit, then the pressure builds
> up and blows the hose right off the bleed screw. If you want to pay
> the shipping for the last one of those I bought and try to unclog it you
> can have it for free.
>
> The other problem is the positioning of the bleed screws, never in a
> good area for attaching a rubber hose to them. not to mention that
> fluid not only comes out the screw hole but all around the threads of
> the screw, so you never catch it all.
>
> Ted
>
>

You can solve the last problem by removing the bleeders and putting a
little Teflon tape on the threads (note: the little hole and the seat
area must be kept clear)

nate

--
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Ted Mittelstaedt wrote:
> "ray" > wrote in message
> ...
>
>>Ted Mittelstaedt wrote:
>>
>>>
>>try out speed bleeders. One man brake bleeding, no special tools
>>required. Loosen bleeder, attach hose into jar, pump pedal. Done.
>>
>
>
> I already tried those, a waste of money. The slightest amount of brake
> fluid contamination will clog the valve with grit, then the pressure builds
> up and blows the hose right off the bleed screw. If you want to pay
> the shipping for the last one of those I bought and try to unclog it you
> can have it for free.
>
> The other problem is the positioning of the bleed screws, never in a
> good area for attaching a rubber hose to them. not to mention that
> fluid not only comes out the screw hole but all around the threads of
> the screw, so you never catch it all.
>
> Ted
>
>

If it's coming out around the threads I think you've got the speed
bleeders out too far. IIRC I only loosen them about 1 turn or less -
the minimal amount needed.

I'd buy them off you... but I only need one more set for the front of
the race car... and they probably aren't the ones you have. (There's
two types for the front of 70's F-Bods - I need the other ones...)

Ray

Get a Mityvac hand vac pump (about $25), then make your jar with tubes.
Mityvac makes some other options too, including a big reservoir with
built-in pump, and an adapter for the bleeder screws. #07400

Put teflon tape on the screw threads so they won't suck air around the
threads.

To pressure bleed, you really need a pro pressure vessel with a membrane
separating fluid and air pressure. Pressurized air over brake fluid
forces air and moisture into fluid and ruins it. Most shops no longer
use them.

It is possible that you vacuum cleaner might pull enough vacuum to get
the job done. Worth atry.


Peter wrote:
> I was trying to bleed my 95 Cherokee brakes, but the fluid hardly
> comes out.
>
> I thought of vacuum bleeding, but I wonder how much vacuum do I need.
> I don't have a pump, but can I use my household vacuum cleaner as
> suction source?
>
> I can take a big jam jar, drill 2 holes on the lid to put in the
> tubes, I already have an adaptor to fit the vacuum hose to the tube.
>
> Would there be enough suction to bleed the brakes? Any better ideas
> apart from spending a whooping $90 on a bleed kit?
>
>
> Pete