Omega Spring Tension?

[Bill Jennings]

Hi All,

I am installing a new omega spring on my 77 Carrera 3.0 and the spring just slides on. I am changing the spring because I think my clutch pedal needs excessive force to depress. The old spring just slides on as well. The two springs are a slightly different size and shape. I was careful to get the right part number from pet for the new spring.

I did the same job on my previous 79 SC and I'm sure I had to compress the spring with some force to get it on. I also seem to remember seeing a thread here where someone suggested compressing the spring then putting a cable tie around it while installing it to make the job easier.

Does the spring need tension from the outset to assist the force to actuate the clutch or does this helper spring begin to work once the clutch arm starts to move?

Thanks in advance for any replies on this.

The new spring is on the left in the picture.

Cheers
Bill

[911Freak]

No preloading needed. Remember you have to snap it forward into position once its mounted. This putting the spring under tension and providing assist.
They can lose their tension and not break as your pedal gets more difficult to depress.

HTH

Jason

[Bill Jennings]

911 freak,
Im not sure what you mean by snap it forward.

In fitting the spring it just pushes on, then I install the small arm that has the set screw
for adjustment plus the long spring to return the small arm.

Cheers
Bill

[Flat6pac]

Snap it forward when you load it on the transmission, usually takes a large screwdriver.
Bruce

[boyt911sc]

Originally Posted by Flat6pac

Snap it forward when you load it on the transmission, usually takes a large screwdriver.
Bruce

Bruce,

I'm getting old and forgetful, but is it the other way around? I also use a large screw driver for leverage to pop it on or off. I got to get under the car see it since I'll be doing a valve adjustment this week. Please advise. Thanks.

Tony

[Jdub]

I am having trouble understanding the statement "..It just pushes on." Are you trying to say that the post on which the spring sits is undersize, or the spring ID oversize?

I would highly recommend you save your old spring - I have done this job 3x times now, twice because the spring was an aftermarket POS. Be forewarned - be sure you have the correct OEM spring.

Addressing the issue: If you have not already done so, you need to rebuild your pedal cluster, then verify that the cable and sheath it ride in are 110% smooth (I would spring for a new OEM one myself). I can guess the clutch pin is about to shear in the pedal cluster or the trunnion pin / bushing combo is now ovalized from wear. Very common, and fixing these items will absolutely transform the clutch pedal feel and overall shifting experience.

[E Sully]

This is how it should look when installed.

[boyt911sc]

Originally Posted by boyt911sc

Bruce,

I'm getting old and forgetful, but is it the other way around? I also use a large screw driver for leverage to pop it on or off. I got to get under the car see it since I'll be doing a valve adjustment this week. Please advise. Thanks.

Tony

Bruce,

I was thinking of the direction which to pull the long screw driver (towards the rear) but the Omega spring goes FORWARD.

Tony

[Bill Jennings]

When I say it just pushes on I do not have to snap it forward onto the transmission. I can just push it onto the post without using a screwdriver.

Its mornng here in Oz I will take a couple of pictures tonight which should be 8 or 9 hours after the time stamp on this reply.

Thanks for your interest.

Cheers
Bill

[Bill Jennings]

Hi All,
Sorry its taken so long to pick this up again, life keeps getting in the way of my Porsche hobby!
I have now put this back together with a couple of new parts (omega spring, short arm and the return spring between the short arm and the transmission case) but not sure it is right.
When I install the long arm with the omega spring I can push the spring onto the post only using my fingers as there is no tension in the spring. However in this position the short arm does not line up correctly whichever spline you put it on to give you the approx 1mm gap.
I pushed the long arm towards the back of the car by prising it with a large screwdriver and found that the omega spring turned on its pivot then stayed compressed and now the short arm is within the approx 1 mm range. After tightening the bowden cable I tried the clutch pedal and it seems much lighter. I now have far more than 25mm travel in the cable though.
Please have a look at the pics to see if anything is amiss.
Cheers
Bill

[Flat6pac]

Anyway, you got the long screwdriver doing right.
You can adjust the pedal engagement at the 2 15mm nuts on the bowden cable under the trans. Moving the bowden forward..nuts going to the rear will move the pedal engagement. It doesnt take much change to change the pedal a lot.
Bruce

[Bill Jennings]

Flat6pac,

Thanks for that I thought I had to do the adjustment at the pedal!

Cheers

Bill

[javadog]

The 25mm cable travel is adjusted at the pedal stop on the floorboard.

JR

[Flat6pac]

The only thing the floorboard adjustment, 17 to 21 turns into the clevis when installing a new cable.
That many turns makes the belden cover adjustable at the transmission with the 2 15mm nuts on the adjuster.
The further you move the nuts to the real the more the adjustment comes up the pedal, or relaxing the beldin drops the engagement of the pedal closer to the floor..until its not even engagable at the pedal.
Bruce

[boyt911sc]

Originally Posted by javadog

The 25mm cable travel is adjusted at the pedal stop on the floorboard.

JR

The pedal travel is adjusted at the floorboard stop. But the clutch cable travel distance of 25 mm could be achieved by pre-setting the correct number of turns at the clevis side and final adjustment of the clutch cable at the transmission side as mentioned by Bruce A.

Tony