Excessive chugging on start up

[Tea]

When starting our 1971 traveller you need to pull the choke out a fair distance. Only then we end up having it chugging away, as though there is too much petrol going in and flooding, but if you push the choke it at all it dies. The only way seems to be to push the choke in slightly and gently push on the accelerator until moderately warmed up.
Once at running temperature it idles beautifully and drives great. I had thought it was perhaps running a little rich, but the plugs are a nice shade of brown after a decent run. Our saloons have never had this issue, so not too sure where to start.

What is likely to cause such extreme chugging on start up and is there a way to alter it?

Also, a completely standard 1098cc with original carb setup.

[liammonty]

The chugging is too much fuel; I.e. too much 'choke'. The choke mechanism does two things: firstly, it richens the mixture, and secondly, it increases the revs a little (called fast idle). The fast idle mechanism can be adjusted, to enable you to weaken the mixture after the engine has started, by returning the choke knob say halfway, without allowing the revs to drop enough to stall the engine. It's as well to sort, as running with too much choke isn't good for the engine. You'll find an explanation of how o do it in any of the usual manuals - it's simply adjusted with a screw on the linkage.

[bmcecosse]

As above - just lift the idle speed with the second screw, when the mixture enrichment is used. Too much petrol causes 'bore wash' - especially on cold start - which seriously increases wear ! The first 1/2" of movement on the (so called) 'choke' knob should only lift the revs - further pull should then drop the main jet to enrich the mixture.

[Tea]

Awesome, thanks for the replies. I will set to on adjusting the screw!

[mogbob]

Check that your air filter is clean and not clogged up whilst you're at it.
Bob