L
lame plumber
As the man said, check oil supply then the pump, have you tried turning it up bit?
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Just because there is oil there, it doesn't mean there's enough to run it. I would bleed it for a bit to make sure of the fuel supply. It's easy and you don't have to pull anything to bits. Then pump off to make sure that the dog coupling is intact and that the motor is running at full speed. Then lid off the pump to check pump filter. Then change pump.
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