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Throttle return spring
#1
I have, I think, too many springs. When I was in the UK, the lever on the steering wheel moved freely and stayed where it was left. Now it has too much tension and moves all the way back to the stop. I can find two springs near the carb. One appears to be a pedal return spring listed in the parts catalog. But it is attached to the operating shaft near the carb, and the other end (hooked) presses on the front of the firewall on the NS. The other spring is near that and attached to the carb throttle lever on the carb and then to a hole on the top of the frame rail. 

Best,

Erich
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#2
There should be a grub screw to adjust friction at the steering wheel control.
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#3
Yes, got that, but I still think I have too many springs and too much tension. It takes some effort to move the steering wheel lever against spring tension.
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#4
On my saloon the standard set-up is just the one return spring on the throttle cross shaft (n°1 in the photo) However in order to ensure that the throttle butterfly closes properly I have added a second return spring (n°2 in the photo) which is a brake light switch spring connected between the end of the throttle shaft and the fuel line incoming to the pump.

[Image: 040_LI.jpg]

Just for info, if that helps.
I don't use the hand throttle.
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#5
The standard arrangement would be one spring. That is the one shown as (1) above and fits between the throttle lever and the firewall as the photo shows. It's a good idea to have a second spring that operates on the actual carburettor butterfly such that if the anything in the throttle line fails (and it can, been there, done that) the second spring shuts the carb butterfly. For cars entered in UK motorsport, that second spring is mandatory. All my three cars have this set up but only one has a working hand throttle. That stays wherever I set it and resists the tension in the two springs. Adjustment is via the grub screw on the hand throttle lever. If you disconnect the second spring that you have, Erich, you'll end up with the standard set up. If your still have a problem with the hand throttle then it something other than spring related.

Steve
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#6
Thank you, Steve. It is hard to tell from Reckless' photo, but is the No. 1 spring the pedal return spring listed in the parts book? Mine is not an in line tension spring. It has a semicircular bit that wraps the cross firewall shaft. When the shaft turns to operate the throttle, the other end of the spring pushes on the engine side of the firewall. It is a quite a stiff spring.

Erich in Seattle
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#7
Erich,

the spring labelled 1 in Reckers photo is this one:

https://www.theaustinsevenworkshop.com/p...aft-spring

There are at least two types of these springs, fitting the incorrect one for your car can result in low or high tension - depending on the permutation.
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#8
Ruairidh, I note that there are types for up draft(what I have) or side draft. As well, there is a spring on the pedal itself that is similar. It lookalike the Seven Workshop only has one type but which type.
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#9
I have a second spring simply to eliminate play in the linkage.
It runs alongside the vertical link from the lever on the bulkhead to the throttle spindle.
On Reckless's picture that's the top end of spring 2 on to the spindle.
I find that the linkage needs careful adjustment to ensure that both full throttle and fully closed are achieved.
My carb is the updraught 22FZ
The aluminium casting on the top of the column is usually worn which makes getting it to move smoothly and stay put in the right place difficult.
The springs/screw assembly are available.
Jim
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#10
Erich,

The one in the link is suitable for your car.
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