RESOLUTION:
Unfortunately, it is not good. After a compression test, Cylinders 4 & 6 only held 50 psi while the rest were 180 psi.
New head gasket, both heads machined and cleaned, all new plugs, oil, and a plethora of other items. Sadly, we are out of the water for at least three weeks! Thank...
I am wondering if it is a lean condition too. I just had a tune-up at the end of last season. I will check spark plugs etc...however, when it's sitting in the driveway with muffs on and I rev the motor, there is no such knocking sound. The knocking only occurs when in the water and driving...
A knocking sound coming from 5.7 GSI engine when accelerating to get the boat on plane. The noise does not exist when revving the engine or at idle speed. Only when accelerating to get on plane.
Few items to note:
Third time out since coming out of winter storage
New Plugs installed before last...
