18 s will not run

[Taid]

Don't know a lot about these things, but have you tried a squirt of easy start ? Should prove whether ignition system is working .. assuming all timing is correct ..

[shaunstaples]

There isn't an air leak on induction somewhere? If you can get your hand over back of the carb and kick it over you should feel the vacuum if all ok. (take plug cap off to be safe) Without the vacuum the engine will have to spin faster to draw fuel.
On my M20 I had only half a manifold gasket on L/H cyl that made it harder to start. The plug should be wet if you've been trying a while.
As Andy and Taid say if you manually feed it with fuel then it should a least fire, or run briefly.

[spookefoote1956]

I have taken to using these o rings with my 389. No air leaks now!

https://www.ebay.co.uk/itm/141455807139 ... 0603744097

[shaunstaples]

I like the thicker o rings, they help insulate from the heat of the head/Manifold. Just got to be careful not to put "any" pressure on flange, like a couple of fibre washers between carb and manifold, take up the gap and support it while achieving a slight nip on the o ring. My T140 had rubbers to do similar thing, and there were thick and thin O rings in the gasket set. I'm trying silicone and a gasket, no O ring. So far so good

[Steffpet]

Hi all,

And thanks for all feedback which is very appreciated. Most of the suggestions you have I already tested and think myself it must be on the fuel side as the spark plug don´t getting wet and I have done everything that can be done on the ignition side such as breaker gab, ignition timing, new sparkplug ( different plugs as well), and I have a good spark. There has been motor oil SAE 50 in the cylinder for 48 hours and I can't see that any oil has slipped through the piston rings but when I tested with Diesel it drained 10 cl at 24 hours, is that normal or can it be that the rings needs to be replaced ? If you think the leakage between the rings and the cylinder wall is normal I will put the engine together again and start all over from the beginning.