Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Tuning/ Carbs coventry climax

Visited the rolling road today with the 4/4 series 1 Coventry Climax.
The carb, Solex 30, which I believe is standard, is delivering way too much fuel above idle. We put in the smallest main jet (120) and air corrector (150), with some improvement, but still black plugs and very poor power (20bhp).
Choke says 30-21 inside and looks pretty narrow.
Also, are Champion D14 the correct plugs?

Any suggestions?

When I had my Climax car, I had a oil fowling problem, resulting in black, wet plugs. The oil flow along the copper lines was too high. It needed a wick in the line to inhibit oil flow. Used pipe cleaners to rectify. Once fixed, it was a lot better. It is a tricky motor to get just right. My current series 1 is a Standard Special with a zenith carb so I am not the best to help.

George Proudfoot is very knowledgeable but always busy.

Cheers,

When we used the smaller main jet, the middle two plugs did begin to lighten a little, so I think we were going the right way.
It would be great to hear from an expert, as we doing the 1,000 Mile Trial Regularity event in July and want to get it sorted!

I've disassembled and cleaned the whole carb, and all was well.
I've now finally found the right plugs (Champion L90C = original KLGF50), which are much hotter, which will reduce carbonising.
Also, correct jets (115 main and 210 air corrector), so that should all help.

I do have one 'odd' bolt which screws into the underside of the choke chamber, over a very small hole into the chamber. It is non standard and seems to blank it, but can't find what it should do.

Can't find a supplier for the correct choke which should be 30-21, mine has a 30-23 in. Any thoughts?

Cheers