7.0L EFI or 7.3L PSD for jet drive boat

I wish I lived in an area where i had all the options but I live in a isolated community where everything comes in by plane so shipping heavy bulky things are extremely expensive. For a comparison I just received four 35x12.50-17 tires for my f150 at a shipping cost of $840. And another $1200 for the tires so I pretty much have to use what is on hand. That is another reason for going jet drive the units weight is a lot lighter than a comparable out drive.

 

Vehicles and bigger stuff comes on a ship that can reach us in the summer time, it is an option but it is a pain in the *** doing so. And also you have to wait till July for the boat.

 

It might be worth while to maybe even go surface drive. Might be the easiest to make work. Although I would need a transmission but again I still have the reverser.

 

Any thoughts on a 2:1 or different ratio overdrive to get the output rpms of the motor a little quicker.

 

Maybe today things have taken a turn for the better. Today I went for a drive out to the junk yard. Looking through all the old trucks and low and behold the last truck I looked at with an engine bay caked full of snow I see what i think is a P pump and six lines coming from it. If it is a 5.9 I hope it is a 94 and newer Cummins, I know they have a 4000 rpm governor spring plus a **** load of aftermarket support. There is a reason it is called the small block Chevy of diesels. I have my fingers crossed hopefully I can get back tomorrow and dig some of the truck out so I can lift the hood more and find out exactly what it is. This should make a much better jet drive motor than either of my last two choices.

 

Well today is even better than yesterday not only one 1995 and newer 5.9, but two were found both with less than 90 000km on them there is a third as well but it is the older f700 grill. If it is a 1994 then there are three. They are free to the taking but absolutely caked full of snow right now. On two of them I was able to dig down to the valve covers and I was able to see a turbo and p pump. The third older one has a turbo you can't see it but there are boost tubes and an inter cooler, can't see the injector pump either. Oh happy day now all I need is a jet to hook one to. The manufacturer of my boat will not answer any phone calls or my emails is there another way to maybe figure out the boats displacement and hull weight. If I post some pics can the shape be seen of the hull and judged if it is jet worthy.

 

Some pics of my fuggly boat the cabin has to go. Something lighter and nicer looking will have to be built.

 

hello P pump

 

some more of the trucks that have the 5.9's in them. in the one picture you can see the back end of the water truck, and the front end of the sewage truck if you look just past the hood of the f700 truck you can see the roofs of the pick up trucks on the far side. That's how much snow has blown around the trucks.

 

Judging by the pictures of the hull (it is a bit hard to tell, but the outboard size gives a clue), I think a 7.3 is far too heavy. Maybe if it is mounted amidships, but the boat looks too small for a 1000 lb engine, plus some sort of gearbox and plus the propulsion unit. I would figure you would be perhaps a half ton above the design mass for the propulsion system? With a round chine like that, that looks more like a candidate for a 4 cylinder gasoline engine, and rather modest speed. Unless I have my sense of scale wrong?

My concern is that you would be building an expensive unintentional artificial reef.

 

FishStretcher, Ya made me laugh buddy with the unintentional artificial reef, that's a good one . right at the moment there is only one sixty on it there are actually twin sixties for it but the one wasn't running right so the guy took it off. I am still trying to get a hold of the manufacturer to get some better measurements for the hull. Oh also the 7.3 is out the boat will be powered with a 5.9 Cummins

 

The boat is a heavy built fishing hull it's beam is 77" and beam at water line is 70" which is two foot down from the rail. 22' OAL, 21' WL this boat was used for collecting soap stone for the Inuit carvers in town here. The hulls bottm is wide and flat near its transom.

 

I went to the boat today and dug as much of the snow away from the transom as I could the hull shape has a pad about 2' wide by about 5' in length tapering to the centre. I drew a crude resemblance of it. plus there are three small skegs that you can see in the one picture of the hulls bottom. The long one runs from the bow and blends to the begging of the pad about 5' from the stern. The two side ones run from the stern to about 6-7' forward. Line drawing bellow.
------
-----------------bow
------

 

I asked the guy today about how much weight in stone they would load into the boat. They would load a tonne of it. So the hull had a tonne of stone, four guys two sixty's fuel for the 100 mile trip home and camping supplies. In my eyes that's quite a load. The guy said with everything in the boat it only ran a couple of inches lower in the water.

 

If that is the case, then you would still have propulsion unit that was about a half a ton heavier than stock. But likely better located than before. I think a Cummins 5.9 is a nice engine, a bit taller than a PSD 7.3. I think both have a lot of combustion noise. If losing a half ton of payload is fine, and the center of mass movement seems ok to you, then it sounds feasible, but perhaps not fast. I wonder if you can incorporate a basic closed loop keel cooler design as well, as it seems unlikely to plane? Like bronze pipe along a skeg. This was common on some inboard boats not unlike this locally in the 1960s and 1970s.