1994 400l two stroke. I just had the piston and rings replaced because i lost compression. After the parts were replaced it started to backfire and wont stay running. Any idea what the problem could be. Thanks for your help.
If it is bad enough then yes. I would tear down the carb and inspect for trash or gumming, 2 stroke carb are bad about that after they sit the oil from the gas being mixed will gum up the carb. If its not starting first put a new spark plug(bad about fouling), if still nothing take off your air box and spray a shot of starting fluid into the back of the carb, if it tries starting you then know you need to go through the carb. Do not use a lot of starting fluid to try and keep it running, it has no oil and could cause engine damage.
Did the old piston break or crack? Seen it a lot, if the old piston has a piece of it break it will drop into the lower case and the crank will roll it around and crack or bust the lower engine case. Check right behind the carb on the engine cases where they join together, this is where they normally bust if they do.
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