F***ing, sucking clutch!

[gacook]

So, I've bled my clutch several times over the past couple weeks, and the clutch still occasionally sucks to the floor, so I decided it was time to replace the slave cylinder. Did that today, and...clutch still sucks to the floor. I assume the next step is replace the master?

[Gawernator]

Replace the master slave and the rubber hose at the same time

[alan6272]

When the peddle sucks to the floor, does the clutch fork also move?

[zedsn]

When my clutch slave hose sprung a leak from rubbing my clutch pedal went to the flor but my fork did not as I couldn't get the car into gear unless I pumped the clutch pedal and then it was stuck in first gear.

[968 GUY]

When one piece goes out, best to replace all. The master and slave cyl. Pressure and supply hose. Replace and flush the brake/clutch fluid.
Helps to raise the rear and not let the tiny clutch res. run low. It is slow to refill itself from the main res. so easy on how many times you bleed in a given period.

[flash968]

yup - and when it comes to bleeding the system, the easiest and best way by far is with a motive power bleeder. i sure wish i had a piece of that company.

[gacook]

I have the Motive, and that's what I've used every time. Also had the ass raised as high as it'd go while doing ig. Visual inspection of the slave doesn't look bad...so I don't know if it was even bad.

Gaw, I was planning on replacing the rubber hose at the same time as the Master =)

As far as the clutch fork moving...I'm not really sure. Normally, the clutch sucks about halfway down and I can lift it back up with my toe. When it does this, I can still push it in to shift before lifting it back up. Occasionally, it sucks ALL the way to the floor, and when it does that, I can't shift, and I can't get my toe under it to pull it up. I have to force it into neutral, pull over and reach down to pull it up with my hand.

[John_AZ]

I agree with the above---

Get new reservoir grommets-2
Clean out all the crud in the reservoir when removed.

Get a new reservoir to slave blue covered brake hose to clutch slave-Pelican sells by the meter-you only need about 9 inches so you have some for your next 944 or help another Pelican out.
If you check, your hose is probably cracked and rotted. Be careful removing off the reservoir.

Bench bleed the MC on the car to get trapped air out of the cavities.
Master cylinder must be level to get out air.





OR--read an excellent write up by member kdjones2000 (move down) on getting the air out of the main line to clutch cyl flex line. Picture 4 & 5

Okay, here we go: The great fix it/upgrade thread

GL
J_AZ

[gacook]

John, are you saying to do this AFTER replacing the Master, or in lieu of?

[John_AZ]

If you buy a new master cylinder, you bench bleed it in a vice.

If you want to make sure you do not have an air pocket in your current MC you can do it on the car as pictured.

Give some of the previous suggestions a try to get the air pocket out before you buy more random parts.

Is there any brake fluid leaking from the MC under the dash by your feet? Pull the rubber boot cover to check also. Or from the MC 'weep' hole by the booster if you have one?



J_AZ

[gacook]

I've seen no leak, and I don't have a booster. I really don't think I have an air bubble in the MC because when I bleed, the fluid is flowing nice and smooth with no hiccups through about a liter of brake fluid.

[flash968]

look closely at the high pressure hose. you may well find it ballooning under pressure.

[mattdavis11]

The easiest way, is to gravity bleed. The cheapest way, is to gravity bleed. Always.

Low pressure slave hose is done. The crack you can't see, is inside the braided hose. It draws in air as well as lose fluid.

[Bradical]

Stop living in the past, Matt.

[mattdavis11]

Ok. I'll use the brake booster hose as my source of vacuum, coupled with a canister so as to not pull brake fluid into the intake, and pull all the air out.

I don't need your fancy tools.

[jhowell371]

Bled mine form the bottom up using a plunger squirt oil can with rubber hose over the tip. Placed hose on open slave bleeder and pushed fluid up. Always did aircraft brakes in this manner. Tapping on the slave cylinder while bleeding helps get trapped air bubbles to move. Just make sure someone is watching at the top to prevent overflowing the master cylinder reservoir.

[JonA]

Stick your head under the dash, behind the clutch pedal and l'll bet you see wet around the clutch master cylinder. You may have to push back the dust cover.
They don't last long.
Then you will have the comfort of knowing that you have found the smoking gun and you're not just throwing parts at this.

Jon

[djnolan]

Originally Posted by jhowell371

Bled mine form the bottom up using a plunger squirt oil can with rubber hose over the tip. Placed hose on open slave bleeder and pushed fluid up. Always did aircraft brakes in this manner. Tapping on the slave cylinder while bleeding helps get trapped air bubbles to move. Just make sure someone is watching at the top to prevent overflowing the master cylinder reservoir.

I think this would work very well but I can't get a wrench firmly enough on the bleeder screw to get it open. Is there a magic wrench for this job?

[The bleeder is rounded a bit]

[mattdavis11]

Originally Posted by JonA

Stick your head under the dash, behind the clutch pedal and l'll bet you see wet around the clutch master cylinder. You may have to push back the dust cover.
They don't last long.
Then you will have the comfort of knowing that you have found the smoking gun and you're not just throwing parts at this.
Jon

Thinking back to the early 90's, a friend had that happen on his 86 951. Never has been a problem with mine. I guess they made them right the first time. 32 years, never an issue with the slave.

[peteb]

Hi,

Is the clutch working except for the sticking to the floor? Does it get stuck on the floor after you push on it or does it drop down its own?

It is possible for the clutch pedal to catch on the carpet and get stuck. Especially on our old cars with firewall insulation falling apart from age and brake fluid leaks.

Just something to check. It happened to me.

Peter