Mrmerlin

I would be betting on a rusted clutch disc sticking to the flywheel or I plate,
that would explain the hard to get into gear with the engine off,
as well as no way to get the trans to shift into a gear while the engine was running.

bernd93

Gents, sorry for my bad "rest-knowledge" of my school english, but I regularly (try to) read here and found exactly a description of a problem of my 1984 928S 5 Speed (ROW Version, 310HP).

Wallys "Problem 1" is what I discover after a change of the master and the slave cylinder (with a new flex line between them). Every morning after engine start I can not shift into any gear - grinding when the shift lever comes close to the gear position. Normally I need to bring the car into reverse to drive out of the garage. BUT: Without engine running I can put in for example the reverse gear - starting the engine with pushing the clutch pedal does not move the car and then I can also release the clutch pedal and drive the car out of the garage. The entire day all shifting works without any problems until a longer break over night, when with engine running after first start I can again not get the car into any gear. I - as explained - then need to to shift into the necessary gear without engine running and after starting the engine I can release the clutch pedal and move the car. We checked several times, that there is no air in the system.

I hope you can understand my problem and hope, that someone can help me?

Thx in advance,
bernd from cologne

Mrmerlin

what kind of flex line do you have?
if its stock i would suggest to get the Greg Brown flex line?
it will make it easier to get all the air out of the clutch Hydraulics

bernd93

Thx, Stan, it is a new flex line like Greg Browns, but from a manufacturer in germany with a very good reputation also. And you think still to be air in the system? By the way: the blue hose from the reservoir to the master is not new. Can this old hose cause air in the system although it is not a pressure line?

Best greetings from cologne!
bernd

docmirror

Very likely still have air in the line. It expands over night. Try this test:

Trans in neutral, start engine, let warm for >5 minutes.
Press clutch all the way in, hold all the way in for 2 minutes.
Now, rapidly release, and depress the clutch ALL THE WAY to the ends(pumping) about 12 times, and on the 12th time, try to shift into a gear.

Theory; By pressing and holding the clutch down, you will compress whatever air is in the line. By pumping the clutch, it will hopefully draw a small amount of fluid in at the top of the stroke and make the pressure plate retract just slightly more each stroke. I used to do this on an old Fiat which had trouble bleeding. It worked for a few weeks until I could correctly bleed it. The 928 clutch is notorious for being hard to remove all the air.

bernd93

OK, I will try and report here. Thanks!

bernd

DeWolf

You need a pressure bleeder. Bled my clutch in 5 minutes.

Mrmerlin

OP how did you bleed the clutch? please post a picture of the clutch line you have and how its routed.
The blue line could cause an air pocket to be in the feed depends on how its routed.
It should make a continious rise up to the tank

bernd93

DocMirrors procedure worked so far. I could immediately shift into a gear. Obviously still air in the system or what does this mean?

And I have no pictures of the current situation/set up available and will post them soon. The bleeding (3 times) was done by my garage with a lot of Porsche experience, but I can not give you details on the equipment used. I will ask them.

Thx all - will post the pictures hopefully this weekend,
bernd

docmirror

Glad to hear we are making progress. A pressure bleeder as mentioned has the advantage of bleeding from the bottom up, so that the air is helped by buoyancy to come out the top and into the reservoir. You may also be helped by tapping on the slave cylinder/line while the pressure bleeder is forcing fluid in the slave cylinder nipple from the bottom. Sometimes tapping dislodges bubbles trapped while fluid is flowing from the slave, up to the master cylinder and into the reservoir. It will also help to drain the reservoir of fluid before starting the pressure bleed process, as it relieves a small amount of fluid pressure(weight) from the line, and also will not push too much fluid over the top of the reservoir.

Edit: pre-heating the fluid may also help. Less viscous.

SwayBar

To bleed the slave cylinder, I did this:

Unscrew almost all the way out the 2 bolts which hold the slave cylinder. The slave cylinder should now be out against the two bolts.

Grasp the slave cylinder and gently move it in towards the bellhousing until it hits. Release the slave cylinder and it will extend itself out against the bolts.

Repeat several times until the slave cylinder is difficult to push in against the bellhousing; finally, bolt it up and torque it down.

I successfully used this technique to replace my slave cylinder, and it's super easy and effective.

bernd93

So, quick udate: the ball socket of the clutch release lever is completly broken. I will now order the part and give a reply as soon a the work is done.

Thx,
bernd

bernd93

Hi gents, my (hopefully) last update on this matter: it was a combination of a broken ball socket and a not correctly adjusted pushrod of the master cylinder. In the english WSM the pushrod should be adjusted to zero clearance between pedal and mastercylinder and then preloaded by rotating one turn. According to the german WSM there should be a remaining gap of only 0,5mm of the end of pushrod in the master cylinder (which is less than one turn). Anyway: now it works/shifts fine.

Thanks again for your support, greetings from cologne,
bernd