Hi I have a 1965 morgan plus 4 all of a sudden the choke needs to held to stay out, if you let it go it closes any help would be appreciated
My '63 +4 does not stay out either. I think it is designed that way. Another words pull choke (fuel enrichment)to start and release choke knob to run. If the choke (fuel enrichment jet) sticks open, put some petroleum jelly on the jet so it does not. There is a "Jet locking nut" that pushes against a cork washer. If the "Jet Locking Nut" is too tight the jet will stick. If it is too loose it will leak.
Make sure after +4 is started that this jet returns to its normal position. It often sticks and the +4 runs too rich.
Read Your manual on SU Carbs. There are a lot of little details that must be attended to properly for it to operate properly.
