A quick hello to you all!

I’m ashamed to say I took the easy route to kit car ownership and bought a prebuilt Westie! I’ve been enjoying driving it over the last few months as well as getting my hands dirty sorting out a few niggles.

A good friend of mine built a seven last year, got involved with this site a bit and has recommended I put a post on here for some first class advice! Well, as it happens I could do with some!!....

It a nutshell…., My carbs went out of tune shortly after I bought the car (DCOE Webber 45's). I had them balanced a couple of weeks ago (cheated and got a professional to do it). This improved the pick up at low revs no end and also reduced the idle speed as I was aware the butterflies on one set of carbs were not closing fully.

Problem is after less than 100 miles the same symptoms have developed again! I want to fix it myself this time...

So after a bit of investigation I think I’ve identified my problem… There is play in the throttle lever (the spare one on the left carb - I’ve drawn an arrow to it in the photo below). If I fully close it by hand the car idles well, however as soon as you apply throttle and let go again it doesn’t return fully to the closed position. To close it again properly is such a small movement (less than 1/2mm), but it probably takes a force greater than that you could achieve with the throttle linkage.

So, if there are any Webber gurus out there have any ideas of what needs adjusting/ tightening/ replacing?

Anyway, that’s me and any help from anyone would be great! before I run back to the mechanic - the shame !

James

The spring on the balance link looks knackered.
Rescued attachment DSC01022.jpg

I would disagree with Peteff.

Those springs often look a bit off.

It looks to me that the lever at the left was originally used for a return spring. Is there a similar one on the other carb?

Of course, this is the wrong place for return springs, as it can twist the throttle spindle. Yet I have seen it many times. The correct place for a return spring is at the same end as the throttle cable attachment.

Is the existing spring(s) strong enough?

If it was me, I'd probably take the simply solution and add a light spring to the lever. Any twisting damage will have already been done.

[Edited on 30/3/08 by lotustwincam]

I strongly suspect what is wrong is the return spring inside that carb isn't working.

Remove the carb --- turn it upside down then unscrew the plate on the bottom with 4 slot head screws. Under the plate you should find a spring attached to a lever that is driven off the throttle spindle via a tiny roll-pin.
I suspect you will find either the roll-pin is broken or the spring is detached or missing.

Another possibility is the throttle pedal hasn't a correctly set stop and is pulling the cable too tight when the throttle is floored. This can cause all sorts of problems with the carb spindles. It is very important to check the throttle cable is not pulled fully hard against the stops when the throttle is floored. The cable needs to be set leave a tiny amount of unused movement at the carb spindles at full throttle or the carb spindles will be damaged.

[Edited on 30/3/08 by britishtrident]

[Edited on 30/3/08 by britishtrident]

Slight correction to above --- although I still think the problem lies with the internal spring, I think either the spring is stretched/broken/missing.
The roll pin is unlikely to be broken as this would affect the accelerator pump.