Volvo Penta engine coupler runout … aka wobble

[highpowerdad]

I picked up a VP 2006 5.7 GI motor with the intention of putting it in a project boat…it is in great shape, however… the engine coupler is “wobbling”. When I measure the runout of the coupler HOUSING (not the spline, but the outer metal housing, on the diameter, at the aft most edge, measured to a common reference point as I rotated the engine), I get .040” of radial movement, so .020” from “concentric” IF I take angle measurements, I get a change of about 0.3 degrees on the aft face of the coupler as I rotate the crank, so, again, an error of about 0.15 degrees from the normal, which, doing the trig, is the same .020” change, so it is a “Wobble”.

This doesn’t seem right, but I have no reference point as to what is good and bad…

SO, is this, ok? Will it cause vibrations, damage bearings? Is this possibly a bad coupler or, worse, a bent engine crankshaft? This engine was pulled from a boat that was in a road accident. The boat was not hit but came off of its trailer when the trailer went off the road into a ditch, the gimbal ring was broken from transom at the top pivot, I assume from the inertia. I had also assumed that with the U-joints and the rubber coupler in line, the engine crankshaft was protected, now I am not so sure. Any insight is appreciated.

Thanks
Scott R.

 

[Scott Danforth]

first, make sure the coupler is mounted properly.

then make sure you are looking at the hub

you dont have a bent crankshaft. forces required to bend the crankshaft would have broken the block

 

[Lou C]

Maybe remove the coupler and make sure nothing of off with the mounting also you might be able to check the run out of the flywheel where the coupler mounts…