944 grinding into 2nd gear and now clutch won't engage

[Scott Hunt]

Hi,
I have a 944 Lux, never gets used enough but in good condition, and have had a slight grinding into 2nd gear over the years but just put that down to an older gearbox (i'm no mechanic!). She's been stored up over winter and I went to move it for the first time and now the clutch won't engage (i have started her up over the winter but not moved her). Pedal feels normal, but when i try any gear it just grinds badly. When the engine is off, I can select a gear and bump forward or reverse but not when the engine is running. Manual Gearbox obvs.

Is this time for a new clutch or is it possibly just sticking?
Cheers

 

[chrisg]

Hi there,

Difficult to diagnose remotely but.....

1. No mechanical change over the winter storage as no movement - i.e. clutch bearings, fork etc

2. Rubber seals and hydraulics do fail with time and lack of usage/lubrication

My best guess, clutch slave cylinder has failed and the clutch isn't being released fully. Often the internal seal fails and the fluid will move but with restricted rod movement.

To fully diagnose this = car up in the air, whip off the small round rubber plug over the clutch mech. then ask someone to push down on the clutch - see if the slave cylinder and fork move.

It could also be the master cylinder seal as well or the flexi hose (check its not leaking or bulging under pressure) that goes from the master cylinder (over the exhaust..... gets toasted over time) to the hard pipe.

So, to fix this - whilst you've got it all apart 1. New hydraulic fluid 2. New flexi hose 3. New Master Cylinder 4. New Slave cylinder - few hours labour and ~ £200 to sort !

Yours

C

 

[Scott Hunt]

Thanks Chris, this is a really good steer for me to explain to the mechanics. I don't have a specialist near me (or know of one on the East Coast of Suffolk), so it will help my local garage to diagnose. Many thanks again.

 

[chrisg]

Scott

there is a theory that you need a 'Porsche specialist' to work on older Porsches - yes specialists are good and have 1. Specialist tools 2. Specialist knowledge..

But.... A good general mechanic should be able to diagnose this and fix it - the hydraulic clutch system on a 944 in basic layout is the same as any other RWD car, BMW, Merc, etc - only slight variation is that it's a pull clutch plate rather than a push.

C

 

[Scott Hunt]

Understood Chris, i do know that some garages have been reluctant to work on older cars as they can't plug in and see the fault easily. Some owners baulk at a few hours exploratory labour to find the issue, so forums are invaluable to assist the potential diagnosis.

 

[chrisg]

Oh and Scott - Slave & Master cylinder clutch seals leaking = well known fault on Porsche 944 !

 

[PSH]

Hi Scott

Going by your description my first port of call would be the gear linkage. The reason I say this is dificulty going into 2nd, the fact that the clutch pedal feels normal and now that you can't get it in gear even with engine off would suggest worn linkage to me. Try looking at this first would be my suggestion.

Pete

 

[bmnelsc]

Good advise here all but you should check clearances also to ensure you are fixing the problem rather than just throwing parts at it...also - when done you will know it is correct. Section 30 of workshop manual vol 2 has the details on travel required to obtain proper operation of the clutch (e.g. the disc will release and not drag) and also how to measure the thickness of the clutch material without having to dismantle everything. This will ensure you don't replace the master and slave cylinders and not solve the problem because your clutch pedal needs adjusting. A non Porsche specialist will need this information to do the job properly but with the manual, any competent shop should be able to do these repairs.

Another thing to look for that the clutch release is moving freely on the input shaft. The release bearing (or throw-out bearing) rides on a guide tube while operating the clutch and this can become worn and "sticky" causing the clutch to not release and producing the symptoms you describe. Checking all the other stuff should show this up but repair is a clutch change scenario as all must come out to service these parts.

 

[944Turbo]

Good advice so far, if you can select gears with the engine off and clutch feels fairly normal (and there is no fluid in footwell or under car) I would try putting it in gear and depressing the clutch put your other foot on the brake and try and start it - I have known cars to rust the clutch to the flywheel this will usually free it.
Tony

 

[Scott Hunt]

Thanks Pete, I can get into gear when the engine is off actually, however I will add that to the list of diagnostics for the garage..! Will revert when I know more. Cheers.

 

[Scott Hunt]

From all the above I'm wondering whether the clutch friction plate has become stuck to the flywheel... this would leave the clutch pressure plate and release bearing able to operate as (and feel) normal but the effect would be as if the clutch was always engaged (pedal up). You would be able to select gears with the engine off but not with it running. If you engage a gear with the engine stopped and then try to start the car, it will jump forwards or backwards according to which gear is selected. Was the car stored somewhere dry over winter, or could it have got damp? This scenario is more likely if there was damp...

 

[944Turbo]

From all the above I'm wondering whether the clutch friction plate has become stuck to the flywheel... this would leave the clutch pressure plate and release bearing able to operate as (and feel) normal but the effect would be as if the clutch was always engaged (pedal up). You would be able to select gears with the engine off but not with it running. If you engage a gear with the engine stopped and then try to start the car, it will jump forwards or backwards according to which gear is selected. Was the car stored somewhere dry over winter, or could it have got damp? This scenario is more likely if there was damp...

That was my thought (better described!), hence the suggestion to try starting it in gear with the clutch and brake depressed,


Tony

 

[Scott Hunt]

Hi Tony,
Sorry - I must have been speed reading and missed that you'd already highlighted this!
Steve
That was my thought (better described!), hence the suggestion to try starting it in gear with the clutch and brake depressed,


Tony

 

[944Turbo]

Hi Tony,
Sorry - I must have been speed reading and missed that you'd already highlighted this!
Steve
That was my thought (better described!), hence the suggestion to try starting it in gear with the clutch and brake depressed,


Tony

no problem, you did describe the fault better and helps the OP more if 2 people suggest it than none!
Tony