What are the symptoms, if any, of a weak master cylinder on a 83 928S?

I have a feeling that my master cylinder might be on it's last legs, partly because 2nd gear is pretty worn, and well, the clutch was replace not to long ago.

Is there any way to check and make sure the master cylinder is functioning at 100%, and not at some half way mark?

Thanks

 

-When I pull into my neighborhood late at night I leave the car in 5th gear, and let it idle through the neighborhood. The Borla exhaust is loud, and the 4.7 litre engine does not mind 600 rpm for a few hundred meters.

Normally, since my driveway is an uphill 10 meters to my garage, I have to give my car a small amount of pedal after selecting first gear. Last night, it kind of kept going on its own....I'm like "Well, that felt kind of weird-" as the fishing bobber that I have hanging from the garage door opener tapped the windshield. I pushed the clutch in and tried to push it into 2nd gear...my right hand met strong resistance. I killed the ignition. Clutch dragging. An un-good thing. Dammit!

I'm like "What the hell is this now-" I pumped the clutch a few times, and it worked perfectly- I even started the motor in the garage, and no clutch dragging was noticed. For a little while I have noticed a small amount of fluid leakage around where the clutch push rod met the insulation on the firewall.

As if I didn't have enough things to fix~

Anyway, I'll be buying a clutch master before long I think....

Normy!
'85 S2 5 Sp~

 

Vib,

Your '83 has the dual disc clutch as does my '81. They are adjustable in terms of spacing between discs and alignment on the shaft.

I have not done the adjustment procedure, but Devek has a write up on their website. If you are going in after the master (Tough job), I would try the clutch adjustment first.

It could be as simple as the slave not pushing the release arm far enough due to the clutch package being positioned too far toward the rear of the car.

HTH,
Scott

 

Second gear synchros wear out first because they get used a lot, and the gear speed differentials are highest there. The Porsche-design synchros are not the most durable - and no, you can't upgrade to a different design.

The clutch hydraulics are stone simple, and will work very well if properly bled. The master cylinder will eventually wear out, but very rarely fails without giving a lot of prior warning. The most common symptom of failure is fluid in the carpet.

In most cases, you can replace the guts of the cylinder from inside the car, without removing the old cylinder housing. Much easier.

If you don't have fluid leakage, I would make certain that it is fully bled (which isn't always easy) and that the intermediate plate is properly centered.

There are two tricks for bleeding the clutch.

After normal bleeding, disconnect the slave cylinder from the bellhousing (without disconnecting the line) and push the operating rod all the way in. Remount the cylinder and rebleed.

If you still have air in the system, you may have to use the Kempf method of bleeding. Pull the dust cover and snap ring on the master cylinder (from inside the car) and carefully pull the piston and cup almost out of the cylinder. Tilt it back so that air can escape from the top, and put it back in.

 

Thanks

when I first read that, it seemed odd to me. My 5th gear gets the most use. I tend to stay on the more economical side of the transmittion as much as possible. Plus, I do alought of long duration drives. It's how I get my wounderful gas milage. :-)

Well, so far, I haven't had those signs, but...

 

ViribusUnits - Synchros are only used when shifting from one gear to another (up or down). No synchro wear ocurs after a gear is selected. As Wally pointed out 2nd gear synchro gets more abuse than other gears because you have high RPM's and low wheel speed (compared to shifting out of 2nd, 3rd or 4th at the same RPM). The synchro is used to 'synchronize' the rotation of the center shaft (running at crank speed usually) to the rotation of the transmission main shaft (driven by rear wheel speed) prior to gear selection. Once a gear is selected the center shaft is effectively 'locked' to the tranmission main shaft. The selected gear can only lock when the two shafts are synchronized (rotating at the same speed). When the synchro wears out it can no longer 'synchronize' the two different rotations and the 'dog teeth' (which perform the 'lock' function) try to synchronize and lock the rotations at the same time causing the spine tingling GRRRRRRIIIIINNNNNNNNDDDD noise you hear. I had the '2nd gear synchro' anomoly until I replaced it. Now it's quiet as a church mouse.