Weber Return Springs

[Slomove]

I read in previous post it is recommended to remove the internal return springs from DCOE Webers to prevent blockage when breaking and install external springs. I had the carbs off today and peeked inside. The spring is suspended from the top on a screw and attaches to the butterfly axle with a little crank. I don't really see how it can block the mechanism even if this extension coil spring breaks. I would expect it to just retract into its bore and leave the return job to the (anyway installed) double springs of the linkage mechanism. That would cause some play but should not be big trouble.

 

Am I looking at the right springs here? Or does the warning not apply to my 45DCOE152 model?

 

Thanks,

 

Gert

[Alan L]

Gert, the internal spring is held in place at the top buy a small disc. If the spring breaks it can fall into the chamber that holds the springs and stop the butterflies.

 

As in the old saying a picture paints a 1000 words so see these links for pictures with the spring in and with it removed.

 

In: here

Out: here

 

Hope this answers your query.

 

Alan and his Yellow and Green 1700 BDR HPC.

 

[Slomove]

Thanks Alan, I did not recognize first it was just a thin disc. And of course you are right: The spring can break at any point and if it happens to be at the top it will just fall down and do funny things.

 

I decided to remove them and install additional external springs.

 

Gert

[StewartG]

Does the removal of those internal springs make any noticeable difference to the "weight" of the throttle action?

I guess I have four throttle return springs on mine, two internal and two external and the throttle action is so heavy it feels a litle notchy. I was wondering if I removed the internal TRS's the cable might be less stressed and move more smoothly.

[Normans_Ghost]

I've had an internal spring break and the throttle stuck open. I drove the car home (about 10 miles) using the ignition switch as the throttle.

 

I've also had the external spring break and have now modified these by replacing them with 2 SU type springs (one for each carb). To lighten the throttle I've fitted a counter spring to the cable at the pedal end.

 

Norman Verona, 1989 BDR 220bhp, Mem No 2166, the full story here

[Westfield]

I have also had the springs break in Weber Carbs (one of the reasons I prefer Dellorto’s!)

 

If you are lucky it’s the bottom eye on the spring that breaks and it just hangs there doing nothing. If you are unlucky it breaks on the top eye and then jams the throttle open!

 

Many years ago when I was an apprentice with Bradburn and Wedge we had a workshop Forman who had a Lotus Seven with a Crossflow in. The car had a pair of Weber Forty’s sticking out from under the bonnet and was the envy of all us apprentices. His party trick was to clock in and then jump into the car and accelerate off up the road at great speed to park it in the car park. One day he did this but as he approached the junction at the top of the road he failed to stop and hit the wall on the opposite side of the junction!!

 

The throttle had jammed open, caused by one of the springs breaking! That was in 1974… you would have thought they would have fixed the design defect by now!!

 

I have just bought a Caterham HPC and one of the first things I did was to remove the internal springs and replace them with a couple of external ones…

 

There are a couple of pictures of the spring bracket on my web site below. If the car had the space between carbs and bonnet I would have replaced the throttle linkage with one of the Weber top mounted ones which give a much better throttle action. Replacing the internal springs has however improved the throttle action.

 

Tony

 

 

Tonys web site

[ECR]

Stewart

 

Yes, if you remove the internal springs there will be less weight through the pedal. You may find that there is not enough though....