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Posted by: mikedsilva Apr 17 2015, 05:04 AM

I'm new to 914 and have no experience with gearboxes...
Tonight, my clutch failed.. the pedal went to the floor.
The cable is fine (new)... But turns out that the "fork" the cable is connected to in the gearbox, seems to pivot back and forth freely.

The clutch is still engaged but that fork piece doesn't appear to be attached to it.

With the basic description I have given, any ideas what it is?

Sounds like I will be doing my first gearbox removal...

Here is a link to a short vid I just took...

https://www.youtube.com/watch?v=F3sahANR2ow

Posted by: pilothyer Apr 17 2015, 06:49 AM

Sounds like the clutch cable tube (inside the tunnel) has broken. If you can verify that it has not, you will be removing the transaxle to see what is wrong and it will be fairly easy to see. The clutch cable tube usually breaks free from the weld at the front and then the back at the firewall. Here is a picture of the tunnel (removed and up side down) the tube in question is the largest one in the picture.

Posted by: edwin Apr 17 2015, 06:53 AM

Mine had a sheared ball pivot in the bell housing when I got it.
Could also be the pedal roll pin which will drop the cable tension as I remember.
Hydraulic is a nice fix if you can get your head around it.

Posted by: bandjoey Apr 17 2015, 09:44 AM

easy to verify. Pull up the carpet, remove the inspection plates by the shifter, use Hand,mirror and light to find and wiggle the tube. If it moves let us know for further instructions.

Posted by: The Cabinetmaker Apr 17 2015, 10:01 AM

Before you go pulling the trans axle, there are a few thing you can check. First, if the tube breaks loose from the front of the tunnel the pedal does not typically go to the floor. It just feels mushy. Check the roll pin at the pedal cluster. It might have broke. Is so, you can move the pedal while looking at the cable end visible from the front inspection hole. If the pedal moves and the cable does not, you lost the roll pin. Then check the trunnion that the cable goes thru at the clutch fork. I've seen that trunnion break and disappear. If it's Ok, remove the cable from the clutch fork. If it moves from one end of the hole to the other, your ball has broken or the plastic ball cup has dissentigrated.

Posted by: SirAndy Apr 17 2015, 10:41 AM

I've seen this happen too.

Time to drop the engine and tranny and get a good look ...

Posted by: Dave_Darling Apr 17 2015, 10:59 AM

with Curt (Cabinetmaker). Check the pedal first, because it's less invasive, but realize that odds are better than even that you'll be tearing the trans off the motor soon.

Fortunately that job isn't very hard.

--DD

Posted by: mikedsilva Apr 17 2015, 12:54 PM

thanks for the replies but we have ascertained it is not the cable or the tube...
It's something in the transmission/clutch itself.

i will try to get the transmission out of the car this weekend...

Posted by: cwpeden Apr 17 2015, 02:04 PM

Make sure to clean the CV bolt heads well and get the correct socket for them. Its called a triple square, 8mm I think.

Posted by: Brian Mifsud Apr 17 2015, 02:11 PM

Me too... by process of elimination I found the nylon (original) "Socket" that that clutch fork pivots in had split. It was not a metal to metal fit on it's backside when new, in fact had about a 1/8" clearance on it's backside. When the nylon failed, the ball had nowhere to go but the WRONG direction. This amplifies the lack of travel in the RIGHT direction, so I could never fully disengage my clutch even with cable completely tightened up.

Dad's lathe and a chunk of bronze fixed that quickly. We machined a replacement that has no clearance behind it, and will outlast the car by lifetimes.

No need to go hydraulic on such a wimpy clutch.. we are only managing 80HP!

Posted by: mikedsilva Apr 17 2015, 03:28 PM

I updated the first post with a link to a short vid I took with my phone...
Here is the link (i don't know how to embed)

https://youtu.be/F3sahANR2ow

Posted by: SirAndy Apr 17 2015, 03:31 PM

It's in the FAQ subforum:
http://www.914world.com/bbs2/index.php?showtopic=97052

Posted by: mikedsilva Apr 17 2015, 07:40 PM

awesome.. thanks


https://www.youtube.com/watch?v=F3sahANR2ow

Posted by: euro911 Apr 17 2015, 08:42 PM

Yep, you need to pull the transaxle. If you rig or block the rear of the motor, you won't have to remove the motor and all the ancillary connections.

Posted by: ThePaintedMan Apr 17 2015, 09:33 PM

At our Chumpcar race, we had a total clutch friction material failure. Probably because it was a used clutch that sat for awhile, it fell into a million pieces when we pulled the transaxle. The good news is a tranny can be pulled, clutch replaced and reinstalled in ~45 minutes if you have 4 guys who all know what they're doing. Still wish I had videotaped it. We had almost everyone under the car at one point, all tightening one thing or another.

Posted by: mikedsilva Apr 18 2015, 11:46 PM

OK.
Got the trans out of the car easily enough... (the two bolts at the top had me stumped for a while...)

Here are some picks of what I found and short video to show the movement soon.
I'm too new to transmissions and this is the first I have ever pulled off a car, so I don't what these bits are meant to do...

It seems the clutch fork has come off the pin.. but how is this possible??
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02512_zps5am31thu.jpg.html
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02513_zpscpo82dum.jpg.html
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02514_zpsw9icos8x.jpg.html

Posted by: mikedsilva Apr 18 2015, 11:50 PM

https://www.youtube.com/watch?v=mb0njVcypMA

Posted by: ndfrigi Apr 19 2015, 12:02 AM

wow that is a super clean transmission after dropping it from your car. I assumed it was recently installed (maybe transmission was recently rebuilt or cleaned before you got the car).

In regards to that video, yes there is something wrong or maybe the recent installation was not done properly.

Posted by: euro911 Apr 19 2015, 12:28 AM

What's the part # on the lever? Looks like it's not long enough

Posted by: Tbrown4x4 Apr 19 2015, 01:24 AM

Looks like it might have been knocked out of place during installation. Was the transmission or clutch just replaced?

Posted by: mikedsilva Apr 19 2015, 01:29 AM

I think you are right...
Is my pivot ball in the same position as everyone elses? If it could be moved in closer, it would fix my problem...

Part number on my fork is
9011167111r (hard to read - the 6 could be something else)

I cleaned up the bits and reassembled.. Here's what it looks like...
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02523_zpsyqfbho0b.jpg.html
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02522_zpsszu2u0lh.jpg.html
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02517_zpskr6wviy6.jpg.html
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02524_zps0uiv1hqa.jpg.html

Posted by: mikedsilva Apr 19 2015, 01:29 AM

I think you are right...
Is my pivot ball in the same position as everyone elses? If it could be moved in closer, it would fix my problem...

Part number on my fork is
9011167111r (hard to read - the 6 could be something else)

I cleaned up the bits and reassembled.. Here's what it looks like...
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02523_zpsyqfbho0b.jpg.html
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02522_zpsszu2u0lh.jpg.html
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02517_zpskr6wviy6.jpg.html
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC02524_zps0uiv1hqa.jpg.html

Posted by: mikedsilva Apr 19 2015, 01:59 AM

googling that part number bring up NOTHING....

Posted by: rmdinmd Apr 19 2015, 05:22 AM

the PET say the part # should be 90111671200.

Posted by: Tbrown4x4 Apr 19 2015, 05:32 AM

Soooooo.... What's the story?

New clutch? New Trans? Bought used? I think we all agree that fork isn't correct, but how did it get there?

Posted by: JawjaPorsche Apr 19 2015, 05:47 AM

Put out a Wtb in classifies..

Posted by: Luke M Apr 19 2015, 06:10 AM

I've got a clutch fork sitting around in a box someplace here.
Shoot me a pm if you still need one.
BTW it looks like something was rubbing on your clutch fork. It could've caused it to be knocked off the bearing unless it was caused after it came off?

Posted by: walterolin Apr 19 2015, 07:56 AM

How about this: http://forums.pelicanparts.com/3245220-post1.html

My fork reads: 9011167120R, 1970, 1.7

Posted by: Mike Bellis Apr 19 2015, 09:55 AM

Many of us have placed a washer under the ball stud to change the fulcrum point, this works well but there are few threads left.

Does anyone have a measurement of the ball and threads? There are thousands of ball studs on the market. I wonder if there is a good aftermarket choice with longer threads.

Posted by: mikedsilva Apr 19 2015, 12:58 PM

I have only had the car a month or so. The previous owner had it 5 years and had all the work done.
Apparently he had a new clutch kit installed by his local shop (different State to where I live).
Unfortunately, I am on my own... he didn't know much about mechanicals and I doubt he wants to know about the issues now!

Posted by: pilothyer Apr 19 2015, 03:53 PM

Obtain the proper clutch fork and you'll be golden.....don't know what the one you have goes in, but it is clearly the wrong one. You need #90111671200 maybe go ahead and get the 2 plastic guides if yours were buggered up.

Posted by: ThePaintedMan Apr 19 2015, 07:10 PM

Definitely not the right fork, or it's at minimum, not engaging correctly.

Interesting in your pictures too - it looks like it was rubbing on the pressure plate as well - see the big gouge in the fork? I bet it was barely engaging before and the pressure plate spinning eventually knocked it off completely. OR vice versa: it came off and then started rubbing on the pressure plate.

Posted by: mikedsilva Apr 19 2015, 10:01 PM

I borrowed a fork from a friend for comparison.. they looked almost identical...
Apart from the location of the ball pivot socket..

On my fork, it is very close to the edge of the fork.
On my friends fork, it is a few mm inset.
That would have to account for some of the difference...
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC01952_zpsk6t1ik2n.jpg.html

http://s1260.photobucket.com/user/mikedsilva/media/914/DSC01953_zps5rlawkug.jpg.html

Posted by: euro911 Apr 19 2015, 10:56 PM

In doing a little more research, found a guy on ebay selling one from a '73 with part# 901.116.712.00 (as Jerry stated) http://www.ebay.com/itm/Porsche-914-OEM-Clutch-Release-Fork-914-901-116-712-00-and-Bearing-/321730882199?hash=item4ae8a7aa97&vxp=mtr

Looks just like the one your friend has. Did you test fit it yet?

Posted by: mikedsilva Apr 20 2015, 12:32 AM

Not yet.. I'm still at work! it's Monday afternoon here...

Posted by: mikedsilva Apr 20 2015, 01:52 PM

Test fit shows perfect fitment!


http://s1260.photobucket.com/user/mikedsilva/media/914/DSC00942_zpsq43oggbm.jpg.html

While I had the gearbox off, a friend loaned me his flywheel lock tool.. so I figured I should check out the slight oil weep.. I've heard of gallery plugs leaking but I think in my case, it is the rear oil seal....

Notice the oil dribbling out...
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC00953_zpslmk7rkea.jpg.html

After a quick clean with brake cleaner...
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC00955_zps4r6yuadf.jpg.html

I can see oil at the bottom of the seal... does that mean it's toast?
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC00958_zpsowv5pami.jpg.html

I've ordered a new seal, but somehow, I think there is more I should be doing while in here...
Does my clutch look OK?
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC00949_zpszxounfgo.jpg.html
http://s1260.photobucket.com/user/mikedsilva/media/914/DSC00948_zpsk767kjfm.jpg.html

Posted by: maf914 Apr 20 2015, 01:58 PM

If the clutch fork issue has been solved, you won't need this attachment. Otherwise, I thought it might be helpful. Is the retaining bracket, item number 6, complete and in place?


Attached thumbnail(s)

Posted by: mikedsilva Apr 20 2015, 02:37 PM

HI, thanks for posting... yes it is in place.
Whilst I haven't mounted the trans back in the car, I believe it should now work properly.

Posted by: euro911 Apr 20 2015, 05:05 PM

Looks like you have the correct lever now

If you can obtain a new rear main seal fairly quick, I'd replace it while you have the opportunity. I'd suggest a Victor Reinz seal if possible.

I'll also recommend that you get a new flywheel O-ring and a new lock plate (both are relatively inexpensive parts).

Posted by: mikedsilva Apr 20 2015, 06:52 PM

Hi
the "lock plate".. is that just the flimsy metal washer that goes between the flywheel bolts and the flywheel itself?
Also, what is the purpose of the felt washer...
When i removed my flywheel last night, I am certain there was no felt washer..
And the needle-roller bearing looked pretty dry too...

Posted by: pilothyer Apr 20 2015, 07:13 PM

You should grease the needle bearing i and by all means install the felt washer. Also a very important step anytime the flywheel is removed you should check and correct the endplay........shoot for .003 "

Posted by: euro911 Apr 20 2015, 07:42 PM

Good call Jerry.

Yes, the lock plate is the large washer.

The 'needle' bearing is known as the pilot shaft bearing. If you don't know if yours was new, won't hurt to get a new one of these as well, just in case the old one was not lubed when installed.

The old one needs to be pressed out, and check the manual to make sure the new one is pressed in to the proper location on the flywheel.