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Posted

Odd issue I'm hoping you fine folks can help diagnose. Recently rebuilt 800XP with new crank, rings, etc. Rod bearing went south so had to replace the crank. Got it back together fine, but only starts at half throttle and doesn't really even want to do that. Checked timing again and dots are perfect, compression 170 on both cylinders, fuel pressure 40ish.  Anything I could run down that I'm missing?

Posted

Could the injector wires be crossed ? Or ignition ?

 

Even though the valve timing is right, it may not be phased with either ignition or injectors.. Seen it on cars.

Posted

@Mech Good call, turned out to be injector wires crossed.  I helped my oldest rebuild the motor and drop it in and he put it all back together.  Woops.  The tip was last night when I could smell fuel a bit while cranking it over.  In EFI the only possible reason to smell fuel while cranking is no compression or a mismatch in squirt and bang.  I knew timing was perfect, that only left fuel and the spray pattern was clean.

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