Saab is '92 9000S sedan
About a year ago I found myself out of town (200 miles from home) my clutch
pedal flat on the floor.we were on holiday. Not a Saab dealer in site. I had
the car towed to the nearest licensed mechanic who told me that either the
clutch master cylinder or its slave cylinder had faied and that if it were
the slave being inside the cluch housing that it was much more labor
intensive and therefore much, much more expensive.

I rented a car, got home and a day and a half later was told that yes indeed
it was the slave.

I authorized the repair and picked up the car three days later and became
$800US poorer.

He told me that as a matter of course he had replace the plate and the
bearing and machined the fly wheel leading me to believe that i had about
40k miles in which I would not have to think "clutch. About a year and 9k
miles later, I left on a straigth through trip of about 600 miles. It is all
limited access highway and I cruised non stop except once at 400 miles for
gas to the end of a toll road at about 500 miles out clutching down as I
approached the booths, my clutch pedal was on the floor. Doing some
undescribable contortions I pulled it up and surprisingly continued normally
to the end of my journey.

Evrything went normally for about a day of "suburban driving. And the,
leaving my hosts house one morning, the clutch was or went to the floor and
no presuasion would re-establish clutching so I had it towed to a repairer
who had done wok for me several years before who could find nothing wrong
but said that my clutch hydraulic fluid was low and he filled it and sent me
on my way. I would say about four oz. (125ml) of fluid leaked overnight onto
the road infront of my hosts. Perhaps an overfill I thought.

I drove home without further repair or incident..600 miles approx.

I drove around town a little. One day last week I was down town--much
braking, shifting and accelerating. Shifting became difficult and, very
surprisingly, My brakes begain to lose effect and the "BRAKE FLUID" light
came on. I made it home. I parked in my drive.

Next day thing seemed back to normal but after a short run the same effects
occurred and I made it home, just. An hour later. The clutch pedal went to
the floor and stayed there. I pulled it up and it went down with my foot and
stayed there.

My drive is on a slope therefore the gears were under pressure and I could
not shift anything.

I had the car towed.

The brakes failing reminded me of an occaision about two moths ago when the
car became difficult to shift and the "BRAKE FLUID" light went on. After
sitting for about a half an hour I re-started and all was normal.

I have learned that the Saab hydraulic system interconnects or shares fluid
with the clutch. This surprises me. (I am a mechanical engineer) but they
are better designes than I could hope to be.

My considered opinion is that it is not a cylider or a leak. But I cannot
even conjecture what it must be.


Please, please someone with knowledge of the Saab's hydraulics pleasehelp so
that I will not in ignorance permit my repairer to replace the entire
hydraulic system.

I really need help and need it ASAP. Thanks a whole lot.

Malcolm













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Malcolm William Mason wrote:

It's either the clutch master or the clutch slave ;-)

If you have fluid coming out of the bottom of the bellhousing,
it's the slave. Needs replacing.

If you're not loosing fluid, or you're loosing fluid into the
passenger footwell (pull the carpet back and take a look) then
it's the master.

Since you say you're loosing fluid under the engine, it's the
slave. I don't know why your replacement slave hasn't lasted
very long, but it hasn't.

This bit may sound odd, but please believe me. IME, if you
replace the slave, the master will fail a short time afterwards.
And vice versa. Maybe it's because of the new fluid, I don't
know. But if you're intending to keep the car, then it makes
sense to replace both at the same time.

--
Grunff

There is an issue with the clutch hydraulic system on 9000`s where the
rubber feed hose from the fluid reservoir to the master cylinder and the
rubber part of the pipe connecting the master cylinder to the slave cylinder
isperished internally by the presence of the brake fluid, these tiny marbles
of rubber get onto the seals and can cause the seals to let by. I have seen
quite a few new slave and master cyliders fail because of this within weeks
of installation. On a few occasions I have changed both hoses and with a
good bleed through it has cured the problem. It is a wise precaution to
renew the hoses when fitting new cylinders, ever wondered why the fluid is
black when you start to bleed the system? HTH Tom, Saabtech.
"Malcolm William Mason" <arpic (AT) toadmail (DOT) com> wrote

Malcolm William Mason <arpic (AT) toadmail (DOT) com> pressed random keys until the following was produced:
On this subject; the reason is so that if you are leaking brake
fluid, before you find out about it by not having brakes, you'll learn
about it by the clutch not working as well - normally a much safer
way to find out. Your "pedal sticking on the floor" failure mode isn't
normal, and I can't explain it...but that's the reason behind the
shared reservoir.

If you're losing fluid, (are you?), it's going somewhere, but if you can't
see a leak, ...

If he can't explain what's happening either, he's probably not the right
person to be working on it. Do you have any Saab specialists (dealers or
independants) in your area? What is your area, maybe someone here knows...

Dave Hinz

davehinz (AT) spamcop (DOT) net wrote:

I'm not sure about other models, but the C900 and the 9000 both
have separate compartments for the brake and clutch fluid within
the shared reservoir. The result is that you can drain down the
brakes (e.g. from a caliper) without in any way affecting clutch
operation. Similarly, you can drain down the clutch without
affecting the brakes.

--
Grunff

Grunff <grunff (AT) ixxa (DOT) com> pressed random keys until the following was produced:

On my '88 900T, the clutch fluid tube into the reservoir was
higher than the brake fluid tube into it, and the clutch would
definately suck air before the brakes would. It's divided, but the
division is not up to the top of the tank. The brake side of it
will get low, but not low enough to suck air. At least, in my
USA-spec '88 900Turbo.

I know for a fact that if, for instance (ahem) you blow your
clutch tube apart (right where the flexible hose is crimped to
the flared steel line, let's say...), you will lose clutch
(of course) but that you do in fact still have brakes...been
there, done that. Drove home anyway

Dave Hinz

davehinz (AT) spamcop (DOT) net wrote:

Hmm...Interesting. I'll have to dig up an old reservoir and do
some experiments.

--
Grunff

"Malcolm William Mason" <arpic (AT) toadmail (DOT) com> wrote

You may have air pockets in your brake or clutch hydrauliic lines.
Could be both. I'd bleed the clutch hydraulic first if I were you.

Yaofeng