Kubota in a boat?

skeets

Well-known member

Equipment
BX 2360 /B2601
Oct 2, 2009
14,618
3,446
113
SW Pa
A bud stopped over the other day and I just finished mowing ( one day the mud wasnt up to my aese) Anyway we talked a bit and he said he was looking for another motor for an old boat he has, He started to look rather lustfuly at my little Bota asking all kinds of things about it and esp the MOTOR! I locked the garage up after he left, I mean you know just in case. So thining about it for a while I begain to wonder if a little Bota motor would work as an inboard? I have seen a lot of diesels on the Great Lakes while fishing for salmon and since these little motors are almost bullett proof why not. So could he use a little Bota motor for an inboard and what would he have to do to make it work right? Im still locking the garage just in case
 

Eddie Jr.

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Equipment
B3200 HSD
Mar 27, 2011
152
0
0
Ottawa Valley, Ontario, Canada EH!
Im still locking the garage just in case
I don't blame you!


There must be a way .... But some issues would surely come up.
Most inboard V6 and V8 gas motors run in reverse (firing and rotation of the engine) so you might have to modify the outdrive .... and so on.
Cooling? Would you keep the rad system or go with the water manifolds you see on big outboards? Wow, this could be fun but I think these two little things might just be the tip of the iceberg ....

I will let someone who knows more about this comment so you get a better answer but I think it's a cool idea for sure!

M.
 

cmorningstar01

Active member

Equipment
B7500HST LA302 FEL 5'Finish Mower B5100E 46" Snow Plow 22 ton splitter
Mar 27, 2011
341
81
28
Pemberton NJ USA
Small diesels are used for power generation and water/fluid pumps in many marine applications, Their fuel effeciency is much better than that of a comparable size/horsepower gasoline engine.

While adapting one to an I/O outdrive would not be impossible and the reverse rotation could be overcome via use of a counter rotating propeller I do not think that they would be practical in a boat that was expected to be able to break water and plane off at speed such as a pleasureboat application, However they are more practical in a work boat application where speed is not a requirement and small diesels are commonly used in slow moving work boats, barges, tugs and sailboats, When used in conjunction with an adjustable/variable pitch propeller they are ideally suited because of their compact size and fuel effeciency.They generally run cooler than gasoline engines and cooling can be done using a closed system where the engine is not exposed to salt water(preferred), Via the use of a heat exchange system or thru an open system where the engine is cooled directly via salt water(less preferable), There are also air cooled diesel engines available which eliminate the need for a water cooling system.
 

skeets

Well-known member

Equipment
BX 2360 /B2601
Oct 2, 2009
14,618
3,446
113
SW Pa
Ok that settles it he aint gettin in the garage no more
 

Bellinghamster

Member

Equipment
B7100 with FEL
Nov 25, 2009
55
0
6
Bellingham, WA
My B7100 is sporting a D950 motor that came from an Onan marine generator, so technically that was in a boat, but not pushing it.

Universal Marine diesels (model M25XP is a D950), and surely others are marinized Kubotas. They fit them with heat exchangers and raw water pumps, and a marine transmission (F-N-R only, with an output shaft designed or thrust loads) and charge a bunch of money.

I've never heard of one mated to an I/O drive, but they're common as straight inboards. Keep a wary eye on your buddy if he's carrying tools near your tractor!
 

Kubota_Man

Member

Equipment
BX24, Rear blade, Front blade, Snowblower, 54" MMM, Box scraper, Landscape rake
Dec 25, 2010
953
2
16
Kellogg, Idaho
In God I trust
However in this case
ALL others will have a escort ;)
 

meanjean

Member

Equipment
Kubota MX4700
Aug 10, 2010
922
2
18
Hazelridge, Manitoba
Quote skeets
I locked the garage up after he left, I mean you know just in case.

Buds don't steal from buds.
I've got another name for people who steal.

Also
Its hard not to admire such a sweet ride!
 

asbug

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B7001 - looks orange to me... Woods 5' scrape, 42" rotary cutter, shreader/chip.
Feb 11, 2011
155
0
0
Varnell,GA - USA
My B7100 is sporting a D950 motor that came from an Onan marine generator, so technically that was in a boat, but not pushing it.
How hard was that to install in the B7100?
Just a good thing to know when and if mine takes a dump...
could be looking for one now.
KC
 

Bellinghamster

Member

Equipment
B7100 with FEL
Nov 25, 2009
55
0
6
Bellingham, WA
How hard was that to install in the B7100?
Just a good thing to know when and if mine takes a dump...
could be looking for one now.
KC
The Onan Marine D950 didn't have a front PTO shaft, but the front pulley had 3 tapped holes that I fab'd a stub shaft to bolt up to. The oil pan (and oil pump pickup) were deeper but swapped easily. The front cover was quite different with the oil filter on the other side which interfered with the frame. I put a remote oil filter on as a work-around. The front cover couldn't be swapped because the cooling passages in the block are different. The cooling plumbing had to be all custom made from copper pipe fittings to fit up to my old radiator - the in and out of the engine block (since it has a water pump) are in different places. The flywheel and starter were bigger but swapped over.

The hydraulic pump swapped over easily, bellhousing bolts matched up... all in all not too bad, but if I had it to do again, I'd probably try to find one with the matching front cover. Also the governor in the injector pump has tighter regulation since it was made to run at constant RPM (making 60 hz AC). I'm not sure if it could be adjusted to soften it up a bit. I could probably swap my old injection pump in, but didn't want to mess with timing.

D750, D850 and D950 engines should all fit... I'm not sure about a D650. I've heard D750's are used in those portable lights they use on construction sites (highway construction), and at least one person I conversed with had swapped one in to his B7100.
 
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skeets

Well-known member

Equipment
BX 2360 /B2601
Oct 2, 2009
14,618
3,446
113
SW Pa
WOW that might make me want to get rid of the quad,, Although I think i would want a lot more freeboard on that thing inthe water