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mikedsilva
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
pilothyer
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.

Click to view attachment
edwin
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.
bandjoey
agree.gif 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.
TheCabinetmaker
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.
SirAndy
QUOTE(edwin @ Apr 17 2015, 05:53 AM) *
Mine had a sheared ball pivot in the bell housing when I got it.

I've seen this happen too.

Time to drop the engine and tranny and get a good look ...
smash.gif
Dave_Darling
agree.gif 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
mikedsilva
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...
cwpeden
Make sure to clean the CV bolt heads well and get the correct socket for them. Its called a triple square, 8mm I think.
Brian Mifsud
QUOTE(edwin @ Apr 17 2015, 05:53 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.


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!
mikedsilva
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
SirAndy
QUOTE(mikedsilva @ Apr 17 2015, 02:28 PM) *
(i don't know how to embed)

It's in the FAQ subforum:
http://www.914world.com/bbs2/index.php?showtopic=97052
smile.gif
mikedsilva
QUOTE(SirAndy @ Apr 18 2015, 07:31 AM) *

QUOTE(mikedsilva @ Apr 17 2015, 02:28 PM) *
(i don't know how to embed)

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


awesome.. thanks


https://www.youtube.com/watch?v=F3sahANR2ow
euro911
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.
ThePaintedMan
QUOTE(euro911 @ Apr 17 2015, 10:42 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.


agree.gif

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. aktion035.gif
mikedsilva
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??
IPB Image
IPB Image
IPB Image
mikedsilva

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

ndfrigi
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.

Click to view attachment
euro911
What's the part # on the lever? Looks like it's not long enough popcorn[1].gif
Tbrown4x4
Looks like it might have been knocked out of place during installation. Was the transmission or clutch just replaced?

mikedsilva
QUOTE(euro911 @ Apr 19 2015, 04:28 PM) *

What's the part # on the lever? Looks like it's not long enough popcorn[1].gif


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...
IPB Image
IPB Image
IPB Image
IPB Image

mikedsilva
QUOTE(euro911 @ Apr 19 2015, 04:28 PM) *

What's the part # on the lever? Looks like it's not long enough popcorn[1].gif


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...
IPB Image
IPB Image
IPB Image
IPB Image

mikedsilva
googling that part number bring up NOTHING....

rmdinmd
the PET say the part # should be 90111671200.
Tbrown4x4
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?
JawjaPorsche
Put out a Wtb in classifies..
Luke M
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?
walterolin
How about this: http://forums.pelicanparts.com/3245220-post1.html

My fork reads: 9011167120R, 1970, 1.7
Mike Bellis
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.
mikedsilva
QUOTE(Tbrown4x4 @ Apr 19 2015, 09:32 PM) *

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?


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!
pilothyer
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.
ThePaintedMan
agree.gif 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.
mikedsilva
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...
IPB Image

IPB Image
euro911
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) ebay link

Looks just like the one your friend has. Did you test fit it yet?
mikedsilva
QUOTE(euro911 @ Apr 20 2015, 02:56 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) ebay link

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


Not yet.. I'm still at work! it's Monday afternoon here...
mikedsilva
Test fit shows perfect fitment!


IPB Image

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...
IPB Image

After a quick clean with brake cleaner...
IPB Image

I can see oil at the bottom of the seal... does that mean it's toast?
IPB Image

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?
IPB Image
IPB Image
maf914
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?
mikedsilva
QUOTE(maf914 @ Apr 21 2015, 05:58 AM) *

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?

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.

euro911
Looks like you have the correct lever now beerchug.gif

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).
mikedsilva
QUOTE(euro911 @ Apr 21 2015, 09:05 AM) *

Looks like you have the correct lever now beerchug.gif

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).


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...
pilothyer
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 "
euro911
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.
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