Clutch goes "POP!" -- Pedal Sticks to Floor -- 1978 911SC

deMeadville · 06-12-2011, 07:00 AM

Dear Pelican Pals,

Ah, the good life. There I am tooling along admiring a "rich district" here in San Francisco on a sunny afternoon, Targa top off. In shifting from 1st to 2nd, I hear this "POP!", the clutch sticks to the floor and suddenly it's "Game Over".

With the engine off, I put the gear lever into 1st, depress the gas, turn on the ignition, lurch forward and make it all the way back home slowly in 1st gear without stopping, right into the garage. (Lots of stop sign running and apologetic hand waves en route).

So: what happened? Right now, the clutch pedal is on the floor and "under load", (i.e. when I pull it back up by hand, it snaps right back down onto the floor).

Anything I can check or do before having (or avoiding) it towed in to the mechanic?

I look forward to your fine consideration and advice. Best

deMeadville

MBAtarga · 06-12-2011, 07:07 AM

BTDT. Broken clutch cable is my guess. That "pop" scared the bejesus out of me!

MBAtarga · 06-12-2011, 07:08 AM

Confirm by looking/reaching under the car and see if you can pull on the exposed cable near the omega spring.

Gunter · Gunter's Garage

If it isn't the cable, check the pedal cluster.

There is a roll pin on the shaft holding the clutch pedal; the pin can shear off.
Also, the hook-up lever for the cable up front can break or the small bushing wears out.

kerthunk · 06-12-2011, 07:38 AM

There is a shaft in the cluster that connects the clutch pedal to the cable in the tunnel. Mine just about wore through in my '79. The pedal is on the floor due to the clutch spring in the cluster. For whatever reason, the pedal is no longer firmly linked to the transmission. Could be the shaft, roll pin, cable or simply the adjustment nuts slipping off at the transmission. Luckily none of it is particularly hard to fix nor expensive and you will most likely end up with a better feeling clutch in the end. Good time to clean up the pedal cluster and get new bushings in there.

KNS · 06-12-2011, 10:49 AM

The shaft on my 1980 looked just like "kerthunk's", it was just about to give way. That car had close to 200,000 miles on it also.

spuggy · 06-12-2011, 11:20 AM

I run a Sachs Sport pressure plate to hold well over 350 ft/lbs of torque, which puts more stress on the whole system (pedal pressure is quite high, stop'n'go traffic is a bear after 10 minutes). I had something similar to the OP happen twice last year...

First time, I went to start the car in the parking lot and the splined arm that goes over the shaft sticking out from the 915 split right down one of the splines and just rotated on the shaft. Exactly same symptoms - pedal bangs on the floor and goes right back there if you lift it, no clutch at all. Wrenches said "never seen one fail like that before". (Sweet, I always love hearing that... :/)

About 3 weeks later, the bracket bolted to the side of the transmission that holds the end of the cable sheath snapped on the freeway when I went to shift. This time, it felt like there was a tiny amount of clutch left on the pedal - just not enough to change gear with

rouxroux · 06-12-2011, 11:31 AM

I had an omega spring pop in one of our '86's....the sound will make you think baaad things have happened!

deMeadville · 07-19-2011, 05:48 AM

Finally a quick note of THANX to all of you above who replied with words and photos as well. 'Twas the clutch cable indeed and $418 later, (including 12 quarts of oil and filter), "we're back in da game!"

Keep it on the road!

GH85Carrera · GH85Carrera's Garage

That happened to my 914 once. I drove home three miles through neighborhoods in 1st gear. Fortunaly it was a early Saturday morning and I knew the route so I avoided the lights and just ran some stop signs.

Pazuzu · 07-19-2011, 06:28 AM

Quote:

Originally Posted by kerthunk

Simply because you included the nice picture...

If anyone else hasn't yet bought and installed our host's pedal cluster rebuild kit, DO SO!

***It includes a brass bushing that goes into this arm and should nearly heal that damage.***

This is not clear from the item description, but it was a great little bonus!
Mine fit tightly into the primary spot, even with the side gouged out like yours (and everyone else's...). If one was worried, I think that filling the gouged region with some JB weld would make the whole arm better than new, and probably good for another 150K miles.

Hey, turns out you can get that bushing separate:
Pelican Parts - Product Information: 901-423-343-00-M105

This can be installed without removing the pedal cluster! Just do it!

rusnak · 07-19-2011, 04:40 PM

This has happened to me several times. Always out of town.

I start the engine in 1rst (good thinking, my man!), and then speed shift to get home. Those in the know will tell you this is the WORST thing you can do to the tranny, and I probably agree, but you gotta get her home, and no way am I going to trailer it to a shop on a Saturday afternoon. Just match the rpm and road speed, blip the throttle, and it shifts without grinding.