Twin Weber 40s cold start device

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Englishmaninwales
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Twin Weber 40s cold start device

I seem to have a small chronic fuel leak from the cold start devices on both carbs. Small amounts of fuel seems to come from around the rear air intake channels on the device and runs down onto the throttle spindle cover plate area and under the carb body, as the car is running. Over time eg this summer’s motoring, this has become an oily mess.
Whilst I’m uncertain of the cause and I never use the cold start device, I wondered about fitting the cold start device elimination kits that I’ve seen available.
Anyone have any thoughts on the cause of the leak (? worn / leaky starter valves) and advisability / experience on fitting this kit?
Thanks
Malcolm

Paul Deslandes
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The Webber cold start device has been described as 'the spawn of the devil' and should be disconnected and never used because, as you have found, they invariably either stick and cause the engine to run very rich, or leak.

As you suggest, the best thing is to remove them entirely as even with the blanking plates fitted the little pistons can still pop up and cause problems.  There are a number of online threads about how to do it with  DIY or proprietary kits.  Google 'Weber cold start device removal'.  I have done it but it was so long ago I can't remember the details!

Paul

Englishmaninwales
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Thanks Paul, that’s very helpful.

Malcolm

HendrixsWhiteSt...
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Malcolm

Just to echo Paul's sentiments - I had them on my crossflow (Paul very kindly 'freed' them once when they were sticking) When I had the Webers refurbished I had them whipped out and blacked off, car runs SO much better now the damn things are history !

'scuse me while I kiss the sky

auyt
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If I can add my experience, just blanking as has been said doesn't sort the issue, this kit is the best way,

http://www.dellorto.co.uk/wp-content/uploads/2016/02/CRK001sht16.pdf.

I tried just the blacking plates and one of the cold start pistons got stuck full open when the car coughed on start and it took me ages to work out why the car was running rich.. bleeding obvious now.

 

Life's too short to drive milquetoast cars

Englishmaninwales
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Yes that was the kit I saw, eliminating the cold start air jets, fuel starter valves and blanking off the air gallery in addition to the blanking plate.

Thanks.

barry watts
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HWS what did the refurbishment involve,  was it a clean up and a service kit? Also who did you get to carry out the work. It's getting difficult to find a weber guru. 

Cheers baz.

pugwash
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Hi Malcolm,  I have no idea what the answer is but as you posted the same question on lotuselan.net I am curious as to what the engine is in!

As you can see from my id photo, I have a foot in both camps.

regards

Mark

PS, I have the "Choke" cold start device on the Elan (Webers) but in over 20 years of ownership I have never touched it.

auyt
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About the only thing that I would like is a hand throttle on start to hold the idle at 500 rpm. 

Life's too short to drive milquetoast cars

Englishmaninwales
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Mark, the engine is a twin cam (in my Elan rather than my Caterham); there is plenty of Weber experience here and I knew the response would be quicker :-)

 

pugwash
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Thanks Malcolm