Pulling my hair out with this engine!

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The reason 2 stroke engines have a pricise ring placement is so the ring end doesn't snag in an "open " port. The typical standard always has the piston reference mark facing the exhaust port. This configuration places the ring gap at a point on the cylinder where there is no open port.

Cool.
So if the ring was 180 out, could the gap still be in a position where it wouldnt snag?
Just trying to learn the basics really.
I might go with a rebuild kit ?
 
So a little update.

I can now confirm the engine is the issue. A friend of mine sent me his FG Beetle for me to store for a while. As he's converting to electric, hes given me the 230 out of it. It's barely been used.

I've fitted the engine after swapping everything over and it runs like a dream om the same 990carb I was using.
I've yet to take the old one apart, but clearly something is wrong in there
 
So a little update.

I can now confirm the engine is the issue. A friend of mine sent me his FG Beetle for me to store for a while. As he's converting to electric, hes given me the 230 out of it. It's barely been used.

I've fitted the engine after swapping everything over and it runs like a dream om the same 990carb I was using.
I've yet to take the old one apart, but clearly something is wrong in there
ok, take pics if u find something wrong with the motor
 
Bored on lunch today so decided to pull the head off the engine.

I can't see any visual damage anywhere.
I also can't see an arrow on the piston top... I would have thought I could see it by now removing the carbon off the piston as much as I have. The ring gap would have been pointing at the Inlet

The head gasket also looks OK although it's a paper one. I can't see any areas where it would suggest a leak.

The only thing I can see is the crank seal is leaking on the clutch side. I wonder if it could have been drawing air in through that

Just a quick few minutes. Needs a full strip and clean really 49858
49859
49860
 
When you dissasemble an engine the components will give you clues at to whats going on . If you look at the piston O.D. you will see that black carbon is blowing past the ring pretty far down the skirt. This tells me the ring is worn out or excessive piston to wall clearence. Like i commented prior a compression test would further help in diagnosing . Now im pretty confident in saying you have a worn out top end. Its really hard to help by only looking at pics, but i am trying to help, it would be a lot easier if i was right there !
 
When you dissasemble an engine the components will give you clues at to whats going on . If you look at the piston O.D. you will see that black carbon is blowing past the ring pretty far down the skirt. This tells me the ring is worn out or excessive piston to wall clearence. Like i commented prior a compression test would further help in diagnosing . Now im pretty confident in saying you have a worn out top end. Its really hard to help by only looking at pics, but i am trying to help, it would be a lot easier if i was right there !
I would say that's a brilliant diagnosis ?
As it was so easy to dismantle, I'll go with rebuilding this lump and I'll stick it in my MCD ?
 
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