Symptoms of Vespa piston the wrong way up
Posted: Mon Apr 11, 2016 11:24 am
Just re-built a Rally200 engine, but not for Rally200 that I have built in a previous thread. So this rally engine has a 12v upgrade, with new LML stator and flywheel and its gone into a GS160. Engine fires up easily and ticks over OK once the choke is pushed in, but will not rev out, splutters and has no power and appears to be running rich in the way of smoke and 4 stroking.
On the carb side and this is a new 24/24E Spaco carb, all jets are standard for this engine. Air mixture screw makes no difference and neither does jetting down the starter jet, or running with air filter off. I've also removed choke wire to make sure that the choke is fully in and fuel delivery is also OK. Suppose I could change carb, but last night, between 2 and 5am, I got to think about the piston and did I put it the right way up
On the electrics side, all stator resistances Ok and change of CDI unit, HT lead, cap and spark plug make no difference.
Now I'm sure that I put the piston the right way round, ie, arrow pointing to the exhaust port. But there again, I get distracted and things go on differently. So what are the symptoms of the piston the wrong way up, are they as I have described.
Thanks
On the carb side and this is a new 24/24E Spaco carb, all jets are standard for this engine. Air mixture screw makes no difference and neither does jetting down the starter jet, or running with air filter off. I've also removed choke wire to make sure that the choke is fully in and fuel delivery is also OK. Suppose I could change carb, but last night, between 2 and 5am, I got to think about the piston and did I put it the right way up
On the electrics side, all stator resistances Ok and change of CDI unit, HT lead, cap and spark plug make no difference.
Now I'm sure that I put the piston the right way round, ie, arrow pointing to the exhaust port. But there again, I get distracted and things go on differently. So what are the symptoms of the piston the wrong way up, are they as I have described.
Thanks