I've had this problem with my 2.25 petrol + Solex carburettor in a minor way for a while, but it's become much more severe recently. I parked it facing uphill the other day, and when I started it, the idle was extremely slow and there was some grey smoke when revving the engine. Above about 20% throttle it seems much happier, but obviously that's not ideal. It's gotten to the point where pulling up to the lights causes it to stall - once there's a little bit of positive G's after stopping it dies, but during braking it's perfectly happy. Naturally, hill starts are now kind of a problem.

I'm not going to be able to work on it for a couple of weeks, but I was looking to get some ideas about how to go about diagnosing and repairing. The things I want to try are:
  • Make sure the needle in the carburettor is seating properly
  • Measure fuel pressure (since the Solexes don't like much above 2.5psi)
  • Check for gunk in the bowl
  • Adjust the mixture.


I know the float height is correct since I checked that recently for unrelated reasons. But all other ideas are welcome, especially if you've dealt with this in the past. Once I figure out the primary issue, I'll check/replace the plugs in case they're fouled from rich running, and it's due for an oil change so I'll do that too (in case it's now got some petrol in it). But these aren't the root cause.

Cheers,
- Will