brake fluid change

#1

I have a 99 Civic with 230k miles and I've never changed the brake fluid.
But I just read an article about moisture content decreasing the boiling
point of the fluid over time. Now I'm concerned about the master cylinder
because I've never changed the fluid. Any thoughts?

Pete

#2

Pete wrote:

Quote:

I have a 99 Civic with 230k miles and I've never changed the brake fluid.
But I just read an article about moisture content decreasing the boiling
point of the fluid over time. Now I'm concerned about the master cylinder
because I've never changed the fluid. Any thoughts?

Pete

Any damage to the master cylinder from lack of maintenance is already
done. That said, changing the fluid now will most likely result in the
master cylinder failing, either at the conclusion of the change, or shortly
thereafter.

--
Tp,

-------- __o
----- -\<. -------- __o
--- ( )/ ( ) ---- -\<.
-------------------- ( )/ ( )
-----------------------------------------

No Lawsuit Ever Fixed A Moron...

#3

Pete wrote:

Quote:

I have a 99 Civic with 230k miles and I've never changed the brake fluid.
But I just read an article about moisture content decreasing the boiling
point of the fluid over time. Now I'm concerned about the master cylinder
because I've never changed the fluid. Any thoughts?

Pete

It's a good idea.

dan

#4

"Pete" <archer1157 (AT) verizon (DOT) net> wrote in
news:fDDql.445$gm6.383 (AT) nwrddc02 (DOT) gnilink.net:

Quote:

I have a 99 Civic with 230k miles and I've never changed the brake
fluid. But I just read an article about moisture content decreasing
the boiling point of the fluid over time. Now I'm concerned about the
master cylinder because I've never changed the fluid. Any thoughts?

Pete

Brake fluid change is ALWAYS a good idea, even on cars that have been badly
neglected, like this one.

Get the dealer or another garage to do it. They have equipment that does
not endanger the master cylinder during bleeding.

--
Tegger

#5

jim beam <retard-trap (AT) bad (DOT) example.net> wrote in
news:sfWdnf3RIcT9eTbUnZ2dnUVZ_gmWnZ2d (AT) speakeasy (DOT) net:

Quote:

Tegger wrote:
"Pete" <archer1157 (AT) verizon (DOT) net> wrote in
news:fDDql.445$gm6.383 (AT) nwrddc02 (DOT) gnilink.net:

I have a 99 Civic with 230k miles and I've never changed the brake
fluid. But I just read an article about moisture content decreasing
the boiling point of the fluid over time. Now I'm concerned about
the master cylinder because I've never changed the fluid. Any
thoughts?

Pete

Brake fluid change is ALWAYS a good idea, even on cars that have been
badly neglected, like this one.

Get the dealer or another garage to do it. They have equipment that
does not endanger the master cylinder during bleeding.

there's not much danger to seals from the process - it's almost always
chemical. fresh fluid causes slight sizing change, and on worn seals,
that can cause leakage. for this mileage, if you're not doing the
work yourself, it's probably cost effective to simply replace.

Honda says differently.
http://www.tegger.com/hondafaq/misc/A011000.pdf

--
Tegger

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

#6

Sounds like both Jim Beam and Tegger are right -- under different
circumstances.

Well eqiupped shops use pressure/vacuum bleeders. So the brake pedal
isn't pumped during the process. However, the brake pedal should be
depressed a little (past the vent port) so the area behind the seal
can be flushed. I think Jim meant how new, drier brake fluid affects
the old, well-moisturized rubber seals (e.g., shrinkage issue).

However, for the smaller or less well equipped shops that do pump the
pedal as in the manual method, not depressing the pedal all the way to
the floor should save the rubber seals.

#7

Sure, the cost of a flush ~$100 is probably better applied towards a
new master cylinder. IIRC the Honda OEM online dealer sells for about
$100.

On Mar 1, 2:54*pm, TomP <road... (AT) socal (DOT) rr.com> wrote:

Quote:

* * * * Any damage to the master cylinder from lack of maintenance is already
done. * That said, changing the fluid now will most likely result in the
master cylinder failing, either at the conclusion of the change, or shortly
thereafter.

#8

I agree that a properly maintained master cylinder should work it's
full usable bore. However, I also agree that brake fluid is
hydroscopic and it contributes to the bore corrosion problems
mentioned.

So in a poorly maintained master cylinder even with a protective
coated bore, I personally wouldn't count too much on the full use of
the backup hydraulic circuit, at least for too long

As far as rubber swell -- I was reading Tegger's site on his MC
repalcement. So I'll leave that to him.

From Valvoline's site, on master cylinder water damage:
http://www.valvoline.com/carcare/articleviewer.asp?pg=ccr20020401mc

"Water Damage
Master cylinder leaks are normally caused by corrosion within the
horizontal cylinder. Brake fluid is hydrostatic [sic], which means it
attracts water. The water in the brake fluid can cause rust pitting
inside the fluid cylinder resulting in fluid leaking past the rubber
plunger. Once this happens the only cure is a rebuild or master
replacement."

On Mar 2, 6:40*pm, jim beam <retard-t... (AT) bad (DOT) example.net> wrote:

Quote:

how? *if the new fluid shrinks the seals, then not pumping them isn't
going to save them.

besides, the master cylinder /should/ work, new fluid, all the way,
regardless. *imagine you cut a brake line, debris or whatever, and now
you only have one circuit working. *suddenly, you're going to want to
use the "unused" portion of the master cylinder real damned quick, and
having that suddenly fail because you've never checked that it worked
all the way last time you bled the brakes could suddenly be just a
teensy weensy little bit inconvenient.

bleeding kits are for speed, convenience and one-man operation, not seal
preservation.

#9

johngdole (AT) hotmail (DOT) com wrote in news:272d7e9b-519a-4bc9-b2a8-bcdf9107bdb9
@w1g2000prk.googlegroups.com:

Quote:

Sounds like both Jim Beam and Tegger are right -- under different
circumstances.

/I'm/ not right, HONDA is right.

Quote:

Well eqiupped shops use pressure/vacuum bleeders. So the brake pedal
isn't pumped during the process. However, the brake pedal should be
depressed a little (past the vent port) so the area behind the seal
can be flushed.

The area behind the rear seal is in the open air, so you can't flush that.
The area behind the front seal has the fluid for the rear chamber. You
flush this area automatically when that circuit is bled.

--
Tegger

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

#10

jim beam <retard-trap (AT) bad (DOT) example.net> wrote in
news:Ao-dnUZK6fhHDDHUnZ2dnUVZ_g2WnZ2d (AT) speakeasy (DOT) net:

Quote:

Tegger wrote:

jim beam <retard-trap (AT) bad (DOT) example.net> wrote in
news:sfWdnf3RIcT9eTbUnZ2dnUVZ_gmWnZ2d (AT) speakeasy (DOT) net:

there's not much danger to seals from the process - it's almost
always chemical. fresh fluid causes slight sizing change, and on
worn seals, that can cause leakage. for this mileage, if you're not
doing the work yourself, it's probably cost effective to simply
replace.

Honda says differently.
http://www.tegger.com/hondafaq/misc/A011000.pdf

written locally, not in japan.

And our cars are driven locally, not in Japan, so the page is most
definitely relevant.

And I'm unable to find any HSN mentions of seal shrinkage due to new
fluid, so I'm guessing Honda has found friction damage to be far more
prevalent than seal shrinkage.

Quote:

bottom line - the cylinder needs to be
effective through the full stroke, any time, any reason. period. if
it's not, it needs to be replaced.

Yes, but if the brakes have failed to the point that you need to rely on
the "last resort" fallback of the one working circuit, the entire system
needs later to be looked at and repaired by a professional (provided the
car didn't get wrecked), so MC condition is not the most important issue
right then. Brakes in that bad shape will likely need a replacement MC
anyway.

Quote:

besides, as you yourself show with
the internal condition of your own master cylinder rebuild on your web
site, the corrosion inhibitors in modern fluids pretty much prove this
to be ancient history.

My brake fluid is changed every single year, as I also say in that page.

--
Tegger

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/