Did you install roller rockers?

The ops engine doesn't sound raspy like the others I've heard. Maybe it's the recording?? The exhaust drops down pretty low on the transom making for a couple of sharp bends. Not sure how much of an effect that would have on sound. Valve timing been verified? Compression ratio also plays a part. Didn't see it mentioned.

L31 with 64cc chambers is advertised at 9.3:1.
That should be pretty happy with the cam choice.
If you haven't done so, please do these things:
1) borrow a piston stop, a degree wheel, and a 1" travel dial indicator.
2) use the piston stop to find TDC on #1. Adjust the stop so that it allows the piston to get within 20 degrees of TDC. Mark in CW direction. Mark in CCW direction. Remove stop. Split the difference, and you will be at TDC. Verify the timing marks on the timing cover and damper match up. Then match up the temporary marker for the degree wheel.
3) use the dial indicator on the intake rocker to find the intake centerline so you can verify that your cam is degreed properly.
Now you never have to worry whether the cam is mistimed or whether your timing marks are erroneous for setting g your ignition timing.

I haven't listened to the clip

I listened to the brief video. I cant tell squat regarding the sound. Too brief, too much echo.
The water pump is not too bad, but the less wobble, the better as far as bearing life.
I have one on a Westerbeke, and I used a dial indicator to tap it around to get it to run on center before tightening the snout bolts. It started with .060" max/min deviation, and I ended up with .014" max/min and it was visibly much happier. As far as your bracket, all the bracket needs to do is keep the pump from rotating. I don't even run a bracket on my Westerbeke. The hoses are stiff and well anchored very close to the pump.

good deal, thanks. I started another thread over in the 'General Q & A' section regarding this boat because I found that I have reversion and am getting lots of water back in. Oil is milky as well.

I'll double check the cam timing like suggestion here. I have the tools to do that.

Yes, I have comp cams 1.52 pro magnum roller rockers installed.

im worried his pump isn’t aligned and he overconstrained it with a stiffer bracket, which would kill its bearing life

thanks, I had a couple people mention like this. I'll get it centered on there with a dial indicator before I call this project finished.

This is a popular conversion from the hideous merc. Brass sea pump. Need to have the pulley that goes with that pump and it's aluminum centering button between the pump and the gm balancer pulley and try reindexing the 3 Allens that attach to the pulley and balancer , should be wobble free .

good information. I'll call Hardin to see if they have it. Do you know of a source for these parts?

R

My Innovations were built with a bracket that went around the post on the side of the pump, which would have a nylon bushing mounted to it. Limited movement/rotation, but allowed for play. Never any issues