OK. This is a STRECH but what do you think. In rougher water I'm into the tabs a little more, the tab down creates way more splash and churn under the swim step. The bilge pump holes are on the underside of the hull in the swim step support as on any other 382. Do you think they could be blasted with enough spray to run back into the bilge ?? I'm lookin everywhere here. Next trip I'm putting corks in all the holes Just to see???? Pickups are on the drives sorta like bravos

As I asked do you have pressure dump valves and water pressure gauges? At the speeds you are hitting you can create some serious water pressure buildup in your raw water lines causing things to leak. I blew two water pumps and had other leaks until I put the Merc dump valves inline before the water pumps - after that everything was good. This is a common problem for high speed boats. My boat only did 80 so yours is probably creating even more water pressure. Could come through your bilge pump, but not as likely - easy to test though as you said just plug the holes and go for a run.

A stretch but not impossible. On a friend's new 350 SS this summer, with the right combination of tabs and passenger weight we had water shooting up into the cockpit from the port floor scupper. The rubber flap in the thru-hull must have been forced open. Weird...

Do you have a sea strainer ? You may need a dump valve on that to.

Your water impellar per the datco engineer's is pumping 35 gallon's per minute at 3,500 shaft Rpm's after that it pretty much cavitates and maintain's 35 gallon's per minute.

However as you reach 100 mph and depending hoe efficient your water pick -up's are it turn's into a presurized system with a capability of forcing 50 gallon's per minute through and past your cavitating impellar.

Mercury has there valve which I think is set at 25 lbs. but that is for your engine block. and furthur research show's 18 lbs is Ideal for the block. But somtimes other blow off lines need to be added to places like the intake manifolds etc. where pressure is building.

Some friends of mine in the racing world running cat's with lambo's running around 170 mph. did a lot of research with data recording info. At one point they could blow the bottom of the cast stainless steel sea strainers right out if the boat aired out and re-entered. Found out in testing they had up to 2200 psi in the sea strainer.

Then is it water pressure or air pressure ?? Either way it was a problem. Everything went to hard pipe. Blow of valves were added to the sea strainer's etc.

Guess I'm saying don't under estimate water pressure at those higher speeds even though your a long way from 170 mph.

Jon

I do not have pressure valves. Merc has different sizes of pickups for the NXT's. They sized them on the initial setup. The Smartcraft screen has water pressure. At speed its about 25 or so. I bought a handful of corks..........we shall see

Yeah, that was very weird. Wish I knew how to re-create it because it was great for cooling off the teak flooring on a hot day!

Next year we need to look at installing misters!