Finger ports, how to find where to put them

[Fast Fred]

it may be jacked up to high on the hull and it's runnin out of water at speed. a water pressure gauge would help.
you could strap the hull to the trailer and back it in the water and go at full throttle, keep her in deep see if she gets hot.
not sure what you are asking on first question, wiesco's are forged, they will grow about .004thou when they get to running temp. so when bored you need to add that .004 in, so the piston size and .008 to .010 thou is bore size, if you bore like stock pistons the wiescos will stick at runnin temp.

[Frank73]

Post some photos of the piston from all sides..
Do you run extra piston to bore clearance to allow for the forged piston

Yes sir, i run extra piston (Wiseco 3130P4) and bore clearance is 2.678in, and my problem is my engine always overheat after run for 300-500mtrs, and i burned 6 Wiseco piston in 1 year time. Until now I cna't solves this problem. Thanks

[Frank73]

Hi sir,

What portion size need to cut (lenght & wide) for Yamaha 50hp 3cylinder at cylinder wall or linear?
Thanks

[Frank73]

it may be jacked up to high on the hull and it's runnin out of water at speed. a water pressure gauge would help.
you could strap the hull to the trailer and back it in the water and go at full throttle, keep her in deep see if she gets hot.
not sure what you are asking on first question, wiesco's are forged, they will grow about .004thou when they get to running temp. so when bored you need to add that .004 in, so the piston size and .008 to .010 thou is bore size, if you bore like stock pistons the wiescos will stick at runnin temp.

Ya I think I jacked up my hull too high, the hull boom same level with bottom hull of my tunnel, i will try lower it down a bit.
What you mean is I need to bored more wide on linear wall than Wiseco piston factory suggest, Boredsized = 2.678in STD = .040in

Thanks