Guru
Joined: 11/02/2018
Location: AustraliaPosts: 2374
| Posted: 09:32pm 25 Jan 2023 |
"how could I inspect the open valve, just looking?"
With the rocker cover removed (photo 2) crank the engine. You should see the valve stems (inside the springs) move in and out.
While you are waiting for the spray try squirting a little petrol into the carburetor and see if that works. Even WD40 may work if it is almost firing, but just needs a little extra flammable vapor.