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I am watching a thread re; a 2017 850 engine with severe piston damage.
Engine is said to have been recently rebuilt!
Photos show scored and darkened colored skirts, and broken top ring landings.
Spark plugs appear to indicate a lean scenario.
The guys are suggesting anything from a bad injector, the Powder Freaks cylinder head, oil system not being primed, and so on.
One member mentioned "detonation" damge.
I am very familiar with the differences between "detonation" and "pre-ignition" in the Auto and Marine engines.
There is typically a concern with the SBCs or the 335 series Fords with a "wedge" shaped combustion chamber, and a full dished piston.
However, the Skidoo 850 offers a hemipherical combustion chamber, so basically, there is no real place for the flame front to hide of which could lead to "detonation".
Of course this does not rule out detonation caused be an extremely lean scenario.
So for you real 2 stroke engine enthusiasts, what is the likelihood of detonation occurring and causing this type of damage?
Engine is said to have been recently rebuilt!
Photos show scored and darkened colored skirts, and broken top ring landings.
Spark plugs appear to indicate a lean scenario.
The guys are suggesting anything from a bad injector, the Powder Freaks cylinder head, oil system not being primed, and so on.
One member mentioned "detonation" damge.
I am very familiar with the differences between "detonation" and "pre-ignition" in the Auto and Marine engines.
There is typically a concern with the SBCs or the 335 series Fords with a "wedge" shaped combustion chamber, and a full dished piston.
However, the Skidoo 850 offers a hemipherical combustion chamber, so basically, there is no real place for the flame front to hide of which could lead to "detonation".
Of course this does not rule out detonation caused be an extremely lean scenario.
So for you real 2 stroke engine enthusiasts, what is the likelihood of detonation occurring and causing this type of damage?
