DDK - Die Deutschen Klassiker

Thanks all for your quick responses. I am puzzeled. If the problem was caused by a leaky fuel line or gasket/seal wouldn't the smell be more apparent all the time rather than only after the engine has been running?

Your thoughts

Heat= expansion still could be the problem , gaskets.

but have you checked the accelerator jets and how much cc of fuel you are getting for each stroke?

if too much this could be your problem..either way get it fixed.

The carbs don’t hold a great deal of fuel, so if it’s been left a couple of days, the amount of fuel in the float can drain out/evaporate and the smell is gone or not as bad. It only needs to be the smallest of leaks to smell strong.

As soon as you start it up again the fuel pump fills the floats up, switch off and if you have a leak around the carb this will drain out and will smell no matter how small the leak is.

I had the very same problem, under normal driving/running conditions you would never have known there was a leak. Switch off and immediately you could smell the fuel but the leak wasn’t visible, it was tiny, but it really did smell.

After running the engine try placing some dry tissue around all the brass fixings/inlet banjo connectors/main jets and see if it gets damp/smells after 5 minutes, it should help you track down a leak or even eliminate the carbs completely. Thats how I found mine, I replaced the fibre washers and tightened everything up (not too tight with the brass ones, they can break) and the smell went away completey.

Hope this helps