Zenoah 320 stroker rebuild engine question

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h3llkittylvr

h3llkittylvr

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So I put in a full stroker engine case and head for the 23. Go to start, there is no suction of the engine drawing air/fuel into the cylinder, instead it is getting blown out of the carb. I have spark, I checked the bypass hole on the carb gasket. The only thing I am unsure of is if the "arrow" on the piston is facing the exhaust. Looking at the old engine assembly, the piston is the same on both sides of the skirt, one side is no different then the other. I am not sure if this makes a difference. There is no fuel in the exhaust either.
CONFUSED??!!??
 
I would assume so as it is a new engine. I installed like I would a car engine, used 2 stroke oil to coat the cylinder and piston/ ring. Assembly went smoothly, engine is sealed well w. moto case sealant, the reed ports as well are sealed well w. no intrusion into the cylinder. I queried AI and it is saying that the Zenoah require the arrow to the exhaust, that this alone could cause a "reverse flow" of the air/fuel which is what I am experiencing. Every pull on the starter wets the entrance of the carb w. fuel. To the naked eye, there is seemingly no difference in the arrow side and non-arrow side. Guess, it is a removal for the Nth time to pop the head and rotate the piston.... ugh!
 
All 2 strokes need the arrow pointed at the exhaust. If no arrow, the ring end gaps should be on the intake side of the cylinder.
 
Ring locator pin will go towards the intake side. Putting on exhaust side may have the ring pop out of piston and break it. Some have had it happen.. others have gotten away with it until they were told it was wrong.
 
I assume you are talking about a 32 and not 23 as you first said.
As previously stated , the arrow points to the exhaust port so the ring gap does not snag in the ports ,otherwise the piston is the same both sides.
Does it have external side ports ? Are they the right way round and sealed to the cylinder? Is the base gasket good and sealed? Is the crankcase gasket sealed ? are the crankcase seals in good condition ? . I ask as it sounds like the engine is not sucking the fuel into the crankcase and then into the ports , just pooling in the inlet.
No idea what AI is on about , as piston rotation will not have any affect other than snagging the rings in a port.
I suspect air leaks on crankcase , cylinder.
 
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