Thottle linkage adjustment

[Ron LaDow]

Ab T has posted the answer several times, but several searches have yielded nothing.
The starting point for the throttle linkage geometry is the distance from the C/L of the upper ball-end (the one that connects via the link to the trans bell-crank) to the front surface of the fan shroud, at (it think) idle.
Having 'searched' here and given the manual a good look (and dropped a note to Ab) I'm hoping Ab or someone here can direct me to the datum.

[Cal Ensor]

Need your email address

Cal

[Doug McDonnell]

https://porsche356registry.org/article/89 50mm

[Ron LaDow]

Thanks, Doug.
Cal, PM sent.

[Mervyn Hyde]

I found this a tricky one to determine until a member here sent me this "... the rod behind the fan shroud between the bell crank and cross shaft. This should measure about 190mm ball to ball". Using that as starting point I managed to get the linkage on full travel and with minimum slack.

[Ron LaDow]

Merv, I'm working on a design of a new product and it will depend on the approximately proper adjustment of the throttle linkage. Ab was kind enough to confirm my memory, and told me where to look in the manual.
In looking at it, I'm pretty sure that (what I guess) is a vertical link dimension is not a determinant, end-to-end. This is a linkage of (depending on how you count) 10 levers and (gimme a minute) 5 (or 6) links.
I'd bet someone in the factory peered intently and said "You better start here, or you can introduce problems forward and back".

[DonCichocki]

Ron,
Cruise control?? Please, please!

[Wes Bender]

Ron, I hope it includes a fix for that troublesome left ball socket on the throttle cross shaft in front of the fan housing.

[Doug McDonnell]

Wes Maybe you need a securing clip: http://www.stoddard.com/90016901402.html

[Wes Bender]

I was referring to the socket in the end of that cross shaft that wears badly if not kept lubricated. All my other balls and sockets are in good shape (no pun intended....). I do have one of those clips on the socket that goes on the ball of the transmission bell crank, just to make sure a wayward stone thrown up from a tire doesn't dislodge it.

And thank you for providing me with my current cross shaft with the little-worn socket.

[Tom Keating]

Peter Zimmermann wrote a Registry article on throttle linkage adjustment- Volume 25 # 5 page 20. I do not know the date. Also B/C factory shop manual page SF25 and SF26
Tom 356C

Added by moderator - Good memory - from 2002!
Link to abovementioned article.
https://porsche356-production-paperclip ... 1396814868

[Mervyn Hyde]

Merv, I'm working on a design of a new product and it will depend on the approximately proper adjustment of the throttle linkage. Ab was kind enough to confirm my memory, and told me where to look in the manual.
In looking at it, I'm pretty sure that (what I guess) is a vertical link dimension is not a determinant, end-to-end. This is a linkage of (depending on how you count) 10 levers and (gimme a minute) 5 (or 6) links.
I'd bet someone in the factory peered intently and said "You better start here, or you can introduce problems forward and back".

You are into some interesting territory there Ron. Kinematic Chain (my engineer son tells me, so I actually do know nothing ...). When I had my motor out recently, on a rainy day I played around with the linkage system on the motor to try to get an understanding of the forces needed to move the system from the lower linkage behind the shroud to the carb balls. I also wanted to try to understand and gauge the amount of travel with different adjustments and the main sources of friction. I do now have a rudimentary understanding but if you can come up with a better way of managing the entire system from pedal to carb, that would be great.

Has anyone used a cable on a 356?

[Tom Keating]

https://porsche356registry.org/article/89 This is the article Ab wrote. Tom