crankshaft balancing

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divebuzzards
Posts: 5
Joined: Mon Jul 09, 2018 1:43 pm

Re: crankshaft balancing

Postby divebuzzards » Wed Jul 11, 2018 8:34 am

Thanks for all the great info. This is what I came up with and it's purely just for a fun experiment. The crankshaft and rod assemblies are from a 71 40hp. With the rotating assembly on the balance rail, the lower cylinder crank balance lobe always wins out and rotates to BDC. It took over two ounces of weight added to the lower piston to get the assembly to balance out. Since the 71 Piston and rod assemblies are 2.4 Oz heavier than the 60's 3 ring piston assemblies, I replaced the lower piston and rod with the lighter older version while keeping the heavier 71 rod and piston on the top. the rotating assembly balanced out perfectly. With the flywheel on, the the rotating assembly will stay in any position over the 360 rotation. Fired it up and she ran sweet. On the water tonight to see the true results.

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Tubs
Posts: 1889
Joined: Thu Mar 12, 2015 7:47 am

Re: crankshaft balancing

Postby Tubs » Wed Jul 11, 2018 8:55 am

The Harley crankshaft, connecting rod assembly
bolts together. He is attempting to get everything
Into alignment. There is in no telling how long
this can take from one assembly to another.
Although being out of alignment will cause
vibration the video is misleading calling it
balancing.
Image Image Image Image

divebuzzards
Posts: 5
Joined: Mon Jul 09, 2018 1:43 pm

Re: crankshaft balancing

Postby divebuzzards » Fri Jul 13, 2018 7:18 am

Project update. Vibrations are gone. The engine runs great.


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