Brake line & speed bleeders

[timbales]

I'm considering for my next maintenance to replace the brake lines and install speed bleeders..... My question is Should I do A full flush out ? or just repace the items and bleed the lines?

[Black_peter]

You will end up doing a full flush anyway..
Unless you are very quick and very very lucky
you will never replace the lines and get the system bled
with out a full flush..(pumping gobs of fluid though)


IMO:
Do not pour pumped out fluid back into the system.
The tiny bubbles created in the pumping/bleeding
process will jest get pumped back into the lines.

Castrol LMA is a very good fluid and cheap at Dennis Kirk..

Protect painted surfaces brake fluid will destroy some paints

If you have a pre 98 I would rebuild the calipers too.
(maybe master cylinder too)

Take your time fitting the lines to the front calipers to
make sure they run just right..
(no twists.. flex well etc)

[The CyberPoet]

Full flush every other year, every year in high humidity locations.
Black_Peter is right about there not being any way to change the lines without doing a full flush.
IMHO: If the lines are to be replaced, replace the caliper piston seals as well and take the time to clean the caliper pistons completely (which is 99% of what a caliper rebuild is).

TIPS:
Never reuse brake fluid. Recycle it with your old oil.
Crush washers on brake systems get used ONCE and only once. Have a few spares around in case you need to reposition a line after installing it poorly.
Wrap the tire with aluminum foil. This will keep brake fluid from getting on the rubber.

Cheers,
=-= The CyberPoet

[timbales]

Thanks great tips..

[trinc]

i would not install speed bleeders with new lines unless you have a mityvac or similar device. the speed bleeder requires a little bit of pressure to open the ball valve - with new 'dry' lines - you will pump all day and never get anywhere.

if you want them anyway - without using a vacuum pump - keep the OEM valves in until you start getting fluid out of the caliper. then you can 'quickly' remove the OEM bleeder screw and insert the speed bleeder.

tim

[timbales]

Wow!things that you learn here...Priceless...Thanks
Now;what about installing the speed bleeders before I replace any of the brake lines and then replace the brake lines? would that also work in the same way?

[trinc]

Wow!things that you learn here...Priceless...Thanks
Now;what about installing the speed bleeders before I replace any of the brake lines and then replace the brake lines? would that also work in the same way?

any time you have a large amount of air ( new lines ) you will have a hard time with a speed bleeder. the ONLY way i see to get around it is to prime the line ( and it's messy ).

$25 for speed bleeder ? you can buy the cheap mityvac for under $40.
( the mityvac - it's a vacuum pump that you attach to the bleeder screw then that vacuum draws the fluid down - it's what the mechanics use - a vacuum system )

hey, cyber - i need a new one want to become a mityvac dealer ?
i'd like the silverline mityvac 4000


tim

[Anonymous]

IMHO: If the lines are to be replaced, replace the caliper piston seals as well and take the time to clean the caliper pistons completely (which is 99% of what a caliper rebuild is).

I did this, and it was a ridiculously easy job...and improved braking more than anything for me...I used very good water retenting grease for it and it worked great.

[Black_peter]

Wow!things that you learn here...Priceless...Thanks
Now;what about installing the speed bleeders before I replace any of the brake lines and then replace the brake lines? would that also work in the same way?

any time you have a large amount of air ( new lines ) you will have a hard time with a speed bleeder. the ONLY way i see to get around it is to prime the line ( and it's messy ).

Agreed, you can also get a syringe.
I have "aquired" a few over the years. You can suck the fluid down to the
caliper or you can push the fluid up into the res. (not with a speed bleeder though). I like using the syringe because it can act like a one man bleeder. The line connecting it to the bleeder can be very tiny and it can
point up so the bubbles go up to the top and not get sucked back in.
Also before sinching the lines tight at the mastercylinder allow a little
fluid to seep out by squeezing the lever. This will assure the fluid is
flowing (it can be a bear to get air out of the MC..)

[timbales]

See I'm confused not! I tough that the purpose of the speed bleeders is to eliminate the hassle and make the hole thing easier.... No you guys are talking bout the pump or the niddle...I'll tell you. I will be doing it myself so I need the easiest and most practical and efficient way of doing it.... Which on ewill that be? In the past I've never used the pomp...had it done in my car with two guys...

[Junior]

... In the past I've never used the pomp...had it done in my car with two guys...

[tzortn]

See I'm confused not! I tough that the purpose of the speed bleeders is to eliminate the hassle and make the hole thing easier.... No you guys are talking bout the pump or the niddle...I'll tell you. I will be doing it myself so I need the easiest and most practical and efficient way of doing it.... Which on ewill that be? In the past I've never used the pomp...had it done in my car with two guys...

I think that the point that trinc and BP are trying to make is that installing speed bleeders on an empty system is a PITA. If you install and bleed the new lines with the standard bleeders then install the speed bleeders and re-bleed the system you should be alll set.

[Black_peter]

Sorry don't mean to laugh..

OK I do..
Don't get twisted up..
This isn't a hard job but you do need to be careful otherwise
it can take hours /days to get brakeing pressure back..
Speed bleeders are one way valves that are supposed to
prevent air (or foul fluid) from re-entering the brake system
once pumped out. However in order to work they have a spring
that pushes against a ball, that seals the bleeder hole once the
pressure is released (lever released) so...
Air bubbles in the lines are squeezed by the brake fluid and thus the
pressure that should squeeze the brakes gets used squeezing the air.
Air bubbles in the line = no pressure for the brakes.
Air bubbles in the line = no pressure for the speed bleeders.

When you replace the brake lines:
* all the fluid in the lines will run out..
*fluid in the Master cylinder will drip out.
*fluid in the caliper will drip out.
All this fluid may get replaced by air.. may..

The new lines are empty.
In my opinion the best way to do this job is:
Replace the lines. Tighten the caliper end but not
the master cylinder end. (not fully)
Attach a syringe (not the needle just the syringe)
filled with fluid to the caliper bleeder (stock one not speed bleeder)
open the bleeder and push the fluid up ( this may take several "loads")
once the fluid fills the system the fluid will start to enter the res.
so keep an eye out that it doesn't over flow..
Close the bleeder.

Now slowly squeeze the lever so a little fluid seeps from the
hose connection, now snug the connection.

Open the bleeder and pump out (into the syringe or into a hose)
at least half a res of fluid. (on each side if working on the fronts)
You should have at least a little pressure..
If the lever is completely dead and no fluid pumps out try pumping the lever with the hose loose (at master cylinder end)
Do try to tighten fully this connection once!
Though I have retightened these connections the crush seals are
one thim use parts.. better safe than sorry..
Once you have pumping action bleed bleed bleed...
Here is a picture of the type I have..
You can buy them (as they have no needles) at a drug store I think...

[The CyberPoet]

Naturally, I have a totally different method than both of these guys when changing hoses.

Loosen the old bleeder valve and let the system drain out through it.
Remove hoses
Install new hoses.
Install the SpeedBleeder valves, with the drain hose, valves open.
Start pouring liquid in at the reservior. Take a short break.
Start pumping the brake lever. It'll take 35 to 50 full squeezes to pump out the whole system of all the air. Keep filling from the top.

Yes, a mityvac or equivilent can be easier to use, but IMHO it can also damage master cylinder piston seals by forcing liquid past them (I've seen this happen to others -- I can't say their seals were perfect to begin with though). But in the last 20 years, I never have used any other method than the one above (with regular bleeders or with speed bleeders) and never had an issue.

Cheers
=-= The CyberPoet

[Black_peter]

Naturally, I have a totally different method than both of these guys.

Naturally

Start pumping the brake lever. It'll take 35 to 50 full squeezes to pump out the whole system of all the air. Keep filling from the top.

Maybe I was unlucky but I pumped 100-200 times and never got
fluid flow until I cracked the banjo fitting at the MC..
After I pushed out some fluid (and probibly some air) I
was able to bleed..

Yes, a mityvac or equivilent can be easier to use, but IMHO it can also damage master cylinder piston seals by forcing liquid past them (I've seen this happen to others -- I can't say their seals were perfect to begin with though).

Why??
With the lever released the piston is open to the res..
Any pulling and pushing is going by the seal but by design..
Not by force..