Originally Posted by rob john buck
Selva 9.9 hp 2 stroke problem
Can anyone help I brought this engine it has a spark, compression seams ok it sucks in and blows out ok it has fired up a few times but now no joy.
I took off fuel pipe going to carb it pumps petrol ok.
I have taken carb off and cleaned the bottom bell chamber has fuel in it.
Not sure what to try next i did try easy start still not firing.
This is a twin cylinder so make sure the plug leads are on correctly and confirm you have a good spark. The idle screw on the carb should be about 1 1/4 turns out but note how yours is set by counting how many turns to screw in then you can return to this if needed. Fuel oil mixture is 2% oil to petrol don't get this wrong too much oil will make it extremely difficult to start and only use TC3W spec oil.
When cleaning the carb (Dellorto models) remove the main jet and soak in carb cleaner or at least neat fuel. The idle drillings in the Venturi can be poked through with strands of soft copper wire and or blown through with compressed air.
These engines like a lot of choke (virtually flood) with a bit of throttle until they fire then knock the choke off and open the throttle slightly. If you have flooded it shut the choke off and turn it over a good few times with the throttle wide open then try again.
If desperate and the above doesnt work remove plugs and squirt fuel mixture into bores. ReFit clean dry plugs with correct leads and give it full choke. It should at least start and try to run, failing that it needs a serious coat of looking at, pm me if you need more help or a parts list.