Throttle Cable Snapped....on my '68 911L....i think

[svonkampen]

Hey,

Throttle Cable Snapped....on my '68 911L....i think....

Just towed her back to my place......As far as I can tell from feeling around down there....the rod connecting the gas pedal is still connected but i don't know....

I am a useless wrench...but I'll give it a shot...

suggestions?

[B D]

What happens if some one pushes on the gas pedal does the linkage on the carbs move? Check all the linkage to start, there are a few connections in the engine compartment just remove the air box to check those. The next connection to check would be under the car left rear by the trans and brake line. Good luck it's a simple system.

[svonkampen]

Ok....

the two push-rods...i think that is what they are called are properely connected, they haven't jumped off.....soooo i think my pedal is fine......I'm thinking my cable has snapped.....

SvK

[svonkampen]

BD my linkage is the culprit.......what page in the haynes manual?

do you know.....trying to find the stuff under the car!!!

thanx,

SvK
(god i'm useless hehehehe)

[svonkampen]

I'm looking at Chap2 Fuel&Exhaust sytems............found Accelerator Pedal stuff....but can't find anything regarding the linkage.

SvK

[B D]

There are also two connections behind the linkage to the carbs follow the rod back. The connection is by the left carb and up against the firewall. You will see a hole there where the rod comes up from below. You need a helper to diagnose this to push on the pedal while you take a look around.

[B D]

Not sure about Haynes for this, they cover so many years and use few good SWB diagrams. Check the linkage in the left rear, jack the rear up first.

[svonkampen]

right....

thanx

svK

[B D]

Check this thread for the daigram, part #18 is what you will see in the left rear. It goes up in to the engine compartment.

[B D]

Sorry here's the thread: Bolt sizes, clutch & Throttle adjustment Q's

[svonkampen]

BD ....urock

Checked underneath the car part "18" snapped !!!!

At least it is an easy fix!



btw: my car goes to TRE on monday for a new engine anyway......so it don't matter

SvK

[svonkampen]

OK what is the name of part 18?.......

Wayne you there?

SvK

[Grady Clay]

SvK,

There isn’t a cable; it is almost all rods and ball-socket linkage.

First check that all the linkage is connected. The links are:
Push rod from accelerator pedal to front bell-crank.
Pull rod at front bell-crank.
The infamous cushion alongside the transmission nose piece.
Links at the transmission bell-crank.
Pull rod between transmission bell crank and engine bell-crank.
Pull rod between engine bell-crank and carb cross shaft.
The two down links to the carburetors.

The most likely cause is the rubber cushion that is in the linkage
between the bell-crank at the pedal assembly and the bell-crank
at the side of the transmission. The cushion is located alongside
the nose of the transmission, just forward of the transmission
mount. The original part was two metal discs connected by the
rubber cushion in tension. When it fails there isn’t any
connection to the engine. You can do a temporary fix with a coat
hanger wire. The replacement part has a metal safety cover that
allows some throttle movement when the rubber fails.

Here is where the cushion is located (red arrow). If the cushion
is broken, you can pop the ball off at the transmission bell-crank
(green arrow) and pull the piece out to work on that half. You
will need to push forward the rubber bellows to unscrew the
front end of the cushion.

Occasionally the link at the transmission bell-crank wears through
(blue arrow). Check that also.
"
"
(C) Dr. Ing. h.c. F. Porsche A.G.


Here is the replacement cushion:




The root cause of this, other than an old rubber part, is the
accelerator stop may be adjusted too far down. This stresses
the cushion when you are at full throttle. It should be adjusted
so when you push reasonably hard, the throttles are just full
open. Of course the floor board must be in good condition.

Best,
Grady

[svonkampen]

Grady i found the problem....it is part 18 that snapped.....see link above by BD....

i need to know the name of this part....

thanx,

SvK

PS
grady u are always so helpful

[Grady Clay]

Here is an illustration of the linkage from the engine forward.
The accelerator cushion is #10 (arrow).
This is the early style without the tin cover.
"
"
(C) Dr. Ing. h.c. F. Porsche A.G.

Best,
Grady

[Grady Clay]

#18 is “Throttle linkage, rear” 901.423.026.03. You usually can repair the damaged/worn part.

Best,
Grady

[svonkampen]

Thanx grady.......mine split at the ring/loopy bit....

How can I fix this?

SvK

[svonkampen]

80 frriiggggiiinnnn $ ?????????

please

SvK

[Grady Clay]

SvK,

The “ring/loopy bit” serves an important function. As the engine moves forward slightly it can slip and not add gas, it can only reduce the throttle opening. It also allows you to check for full throttle at the carbs while actuating the linkage only as far forward as the “ring/loopy bit”. To check for full throttle you need to actuate the accelerator pedal and adjust the stop.

Repair:

Probably the connection at the transmission bell-crank is equally worn and in need of repair. The best solution is to find some good used parts. You are going to want to replace the plastic bushings at the transmission bell-crank with new “while you are there.” Use this oppertunity to inspect the cushion. Even the updated part can have internal rubber failure that is difficult to detect.

Fixing the worn parts is difficult at best. I have seen some real Rube Goldberg attempts. The important thing is to not defeat the slip ability in the linkage. Put your creative hat on and post your solution.

Everyone needs to clean and grease that linkage spot at regular service; like oil change.

Best,
Grady

[304065]

I just cleaned and lubricated mine tonight (my linkage that is) and found that some PO had omitted to include the cushion! And I just got through replacing the one on the '71. . .