Here is the deal. My 419 FASTech foams up the water too much for the generator pickup to feed the strainer and keep the gen supplied with enough water to run on plane or at 40mph. I know there are other stepped hull go-fast boats that can run their gens on plane but their pickup location is very different than this 419 FASTech.

My question: Can the generator run fine on plane with a 400SS or 370SS? If so, where is your pickup located?

I am going to make this 419 gen run on plane so I need to find a workable location of the strainer pickup for this to happen.
TIA

I think you need to install a transom water pickup like high x-dimension go-fast guys run for motors and intercoolers.

See here: http://teaguecustommarine.com/em0011...-1-00mnpt.html

My 400 SS the pickup is at the front of the engine compartment thru hull. There are 2 steps in front of it. I found 2 burnt impellers in the junk box that came with the boat..hmmm assuming the previous owner tried to run the gen on plane? I have run the genset the whole summer at idle up to 10 mph with no issues. I did have issues with my 382 though. When I ran fast with the gen seacock open and the genset off it would fill the gen with water. Too much water pressure on the pickup? I had to disassemble and clean. I think with transom pickup you may easily over pressure the system? I think its a tough challenge to ask the genset to gulp air then be blasted with water? Way big strainer to create a buffer/reserve? Lotsa impellers/EZ to change...and away you go.

Yes that may be the case. That is how Fountain is set up and also what I can do here too.
I'm curious to see if the stepped SS hulls accommodate this from the factory as a suggestion of what I can do consistent with Formula production or if I'm on my own with this.

I think you just answered my main question or query on the Formula set up. "There are 2 steps in front of it." That is the source of the foam and problem of feeding the strainer inlet at speeds where the function of the steps are active. I would think the same you thought, that the former owner could not run the gen on plane at speeds where the steps are foaming up the water and it resulted in burned impellers. Your 400SS pickup is in the same location that my 419 and your 382 are.

That said, your flooding situation on the 382 is very curious to me. The pressure control method typically used for generator plumbing is to run an open one inch or larger line, I think Formula has 1 1/4" line "T-d" off the strainer inlet, so if the inlet pressure exceeds 7-11 psi it is vented out the back of the boat, specifically to prevent over pressuring the impeller and flooding the gen. Either your pressure relief line was restricted or missing from your re-power or burned impellers allowed flooding at lower pressures. My 419 is plumbed properly for this function and all the 382's I have seen were also. Formula did a text book, jamb up job on the details for proper generator/strainer installs in their product. Now they need to up the bar to running on plane.

I am going to get my 419 there and it looks like the transom location will be the fix. Now I need to know the optimal flow areas of Formula's steps for my pickup position.

Would it be possible,
With the stepped hull aerated water to the scoop and the second/bypass hose cause impeller cavitation and burning. The second line that saves my non-step Genset from over pressure, may be your starvation problem?
Maybe restrict the overboard hose just a bit to compensate, rather than relocate the pickup.

The gen issue was before the repower with all things box stock. I always kept the seacock closed after that. Open only when running gen...

Ok. That is pretty much how a person is directed to do it in a typical sea trial.

I can run on plane with the gen running, never had a problem, although I have a 330...

I have thought of exactly that just in passing and now that you mention it I really wonder about testing the idea. If the transom pickup could supply enough water for engines and gen with so much foam under the boat then the air must be packed or somehow vented/restricted successfully resolving the issue. I have wondered about using a pressure guage and a video cam to see at what point the water flow dynamic changes because the gen will be running fine and then over temp shut off shortly after running on plane. The water is there sitting still then the boat gets moving where the inlet should "scoop" the water but slowly something changes to starve the impeller somehow. The routing of the lines have made me wonder if there is a cavitation possibility and now that you mention it I'm sure I can create some tests to pin that down. Using hydraulic principals I can see one issue where the large discharge line could also become a syphon issue if the water speed is excessive and for fossil fuel to get flooding with this same set up there must enough water to run the gen.
Before I go cutting holes I will work with some flow dynamics here and answer some of these quandaries.
I would love to find a flow dynamic in hose routing or inlet size that would resolve this without further mods but in any case I will have my gen running right on plane.
Thanks for the thoughts.