Clutch/shifting issue

Teamchefen · 03-06-2011, 09:52 AM

Hi!

My son is a beginner in sports car racing with a 944 S2.
I'm not a great mechanic and now asking for some help/tips...

After last race we noticed a big loss of brake fluid. Obviously a leak somewhere...
In the last laps of the race it was also hard shifting, in all gears.

Can the low brake fluid level (below min and the hose to clutch cyl.) have something with the shifting issue to do?

Please help us, next race in just a few weeks...
Sorry for my bad swenglich (sweden).

/Johan

Rasta Monsta · Rasta Monsta's Garage

8|

ernie9944 · ernie9944's Garage

Quote:

Originally Posted by Teamchefen

Hi!

My son is a beginner in sports car racing with a 944 S2.
I'm not a great mechanic and now asking for some help/tips...

After last race we noticed a big loss of brake fluid. Obviously a leak somewhere...
In the last laps of the race it was also hard shifting, in all gears.

Can the low brake fluid level (below min and the hose to clutch cyl.) have something with the shifting issue to do?

Please help us, next race in just a few weeks...
Sorry for my bad swenglich (sweden).

/Johan

Check underneath the car first(bell housing -starter area if the clutch cyl is leaking there will be oil dripping in that area ) if not check behind the clutch pedal & underneath for oil trace on your carpet or pull the rubber cup on the (clutch master cylinder no-16 )if needed try to do both clutch & master cylinders at the same time , since usually when one let go the other one is not far behind.If like mention you got a large brake fluid loss it should be easy to spot.Good luck

Swenglish is perfect.

Teamchefen · 03-06-2011, 10:49 AM

Quick reply, great, thanks!

No oil dripping inside car.
I have to put some clean paper on the floor under the car, old floor - lots of old dripping...hmmm.

But if the brakes are leaking, brake tube or brake hose, can i then get a clutch issue?

ddbach · ddbach's Garage

As Ernie noted, the clutch is hydraulic and shares fluid/pressure with the brakes.
Did he notice any change in the feel of the clutch pedal?

Some recent threads on clutch related issues here:
Need advice from the clutch gurus

Clutch issue-not disengaging, in spec

Clutch pedal on the floor

And some how-to information from Clark's Garage
Clutch Slave Cylinder Replacement

Clutch Master Cylinder Replacement

Good luck getting this sorted out.

Teamchefen · 03-06-2011, 09:01 PM

Both me and my son thinks that the clutch pedal feels the same as always...

John_AZ · 03-07-2011, 03:40 AM

You may have a bad MC (master cylinder) rear seal. There is a "weep" hole where the MC mounts to the brake booster.

Another area is the rubber clutch hose from the slave cylinder. It deterioates.
If you do the slave & clutch MC, replace the hose.

GL
John

Teamchefen · 03-07-2011, 05:32 AM

Thanks, i will check for leaks.

One guy told us that it could be the pressure plate or clutch plate...?

No vibrations or noise from clutch, just hard shifting.

Teamchefen · 03-07-2011, 11:05 AM

A new discovery...
I can move the engine forward and backward, by hand, maybe 2 inches.
Nothing to the left or right.
If there are any loose bolts on the clutch housing or central tube, can this be the shifting issue?

SolReaver · 03-07-2011, 11:37 AM

IF you have the car in gear and the engine turns relatively easy then kinda clunks to a stop both back and forward..... Leans towards a hockey puck that has let go and is hitting its stops. Do you have a hockey puck? (original rubber centered clutch disk) have you seen little rubber bits coming out the bottom? there is an inspection hole and you can pull a shield. You might have to remove the starter to see.

Teamchefen · 03-07-2011, 12:23 PM

Nopp, no clunks or rubber bits at all.

Rasta Monsta · Rasta Monsta's Garage

Quote:

Originally Posted by Teamchefen

I can move the engine forward and backward, by hand, maybe 2 inches.

924RACR · 03-08-2011, 04:19 AM

Sounds like it's time for some motor mounts, perhaps!

Also, beyond checking for a leaking brake or clutch MC, note that the brake reservoirs of these cars will lose fluid out the top vent on-track.

To deal with this, we don't quite fill ours all the way, only just above half, and we zip-tie a folded paper towel to the cap itself to soak up any spills/weeping.

But that wouldn't cause a compromised clutch pedal, so check for those leaks. Unless if uncovered the feed hose for the clutch MC.

Also, the excessive engine motion wouldn't help shifting...

HTH...

924RACR · 03-08-2011, 04:20 AM

PS - often you won't necessarily see liquid, but the carpet will be damp on the firewall... or do you still have carpet?

Teamchefen · 03-08-2011, 06:47 AM

Thanks for all replies, great!
No carpets left in the car. All clean and painted.

What do you think about that i can move the engine forward and backward? Loose bolts at the bell housing?

(Wow, my swenglish really sucks...)

Teamchefen · 03-09-2011, 06:49 AM

Went under the car this afternoon for a look.
Three bolts between bellhousing and central tube missing. Fourth one not tightened and a gap appr. 1/4 inch.
I put new bolts and tightened it together, easy and no tensions.
Now i can't move the engine at all, totally stiff all directions.

I then started the engine, with the car on jack stands, and so far it feels great again. Easy, smooth and precise shifting.
This weekend i'm going to change the brake fluid, bleed the brake and clutch and take a testdrive.

So far, thanks a lot for all your help and tips. I'll be back after testing.

SolReaver · 03-09-2011, 07:07 AM

move the engine...Oh, I thought you meant rotate...my bad.

Glad to hear it isn't a clutch. 3 bolts and you are good to go. Needless to say you should prob inspect and check the torque on anything you can get to. Congrats and happy driving.

924RACR · 03-10-2011, 04:22 AM

OMFG!!!

You got lucky. No wonder it was hard to shift! LOL

Like Sol said - now is the time to properly prep the car. Check torque on everything whether or not you can get to it easily; if it would ruin your day by falling off at speed on the track, torque it properly.

Then put a paint mark on it, using a paint pen, so you'll be able to tell if it loosens up again in future, without even pulling out a wrench.

At very least do this to all drivetrain mounts and suspension components.

924RACR · 03-10-2011, 04:23 AM

PS - I hope you used 8.8 rated bolts??

Teamchefen · 03-10-2011, 04:41 AM

My son is spending the whole weekend tightening everything, and i mean everything from top to bottom.
Yes, i used 8.8 rated bolts and tightend them properly.

Finally, back in business and heading for the first race of this season.