To Isuzu or not to Isuzu

[psahd]

To Isuzu or not to Isuzu
Hello to all you wise seafarers and armchair sailors alike! I am looking for meaningful input from the forum on whether it would be a reasonable idea to replace my 2 Yanmar 3GM30's with 2 C240 Isuzu's

I have a 44' Dean Cat and I am happy to and can afford to carry the extra 100kg per side, being the difference in weight between the Yanmar and the Isuzu.

Please hit me with your insightful reasoning!

[Oldwheels]

Why change? Yanmar is a good engine with good availability. Next up the Kubota.

[tkeithlu]

Trading out for different engines has a pretty bad reputation on the forum. The locations of all the hoses, cables, through-hulls and wires are going to be different, the mounts may be different, and the designer didn't leave a bunch of otherwise pretty space that sells boats for something like engine access. The one known success in recent posts was a forum member who actually built a cardboard engine, to the new engine's specs, to see whether it would fit.

Why do you want to go from 29 HP to 75HP on each side? Your 58 HP easily brings your boat to hull speed. 150 HP will use a bunch more fuel, if you are trying to support OPEC, but it will only marginally and at great expense make your boat faster.

[grantmc]

Do It, change them over.
But let us know how it goes.
The Isuzu C-Series are great little motors, but I've never heard them being described as 'marine' engines. At least not by Isuzu.
Certainly they've been used in boats with great success.

[psahd]

What I am trying to gauge is whether I will be adding value or not, both in terms of financially as well as functionally. The Isuzu has been made as a marine motor. Mechanically it would require some thought to make a good transition and that can be done.
A negative to the project would be that the SD 20 saildrives would need to be replaced, meaning a difficult haulout. Closest haulout facility would be 400NM away. Logistically it would be difficult but what I am trying to arrive at is: Does the benefit, if any, outweight the challenges.

[Westcliffe01]

Any reason you are not considering a suitable HP Kubota engine instead ?

[psahd]

I can get the Isuzu's at a really good price. Kubota's, I understand are expensive and not available in SA.

[Searles]

The Isuzu c240 is a execelent small diesel,I rebuilt my own at 19k hrs,could still buy a brand new long motor of the shelf from Isuzu,rebuilt the exhaust heat exchanger unit ,all easily together parts ,a failure in the tube bundle was the cause of the failure leading to the rebuild ,marinised by North American marine ,,a quiet smooth engine set at 3k rpm 62 hp ,verry happy customer .⛵️⚓️

[skipperpete]

Originally Posted by psahd

What I am trying to gauge is whether I will be adding value or not, both in terms of financially as well as functionally. The Isuzu has been made as a marine motor. Mechanically it would require some thought to make a good transition and that can be done.
A negative to the project would be that the SD 20 saildrives would need to be replaced, meaning a difficult haulout. Closest haulout facility would be 400NM away. Logistically it would be difficult but what I am trying to arrive at is: Does the benefit, if any, outweight the challenges.

Putting in the Isuzu’s goes way beyond a difficult haulout. Are your current engines under the bed in the aft cabins?, if so, the height of the isuzu might be above the bedbase level. Extending and reinforcing the engine bed and saildrive bed is problematic and if you use an SD60 it lifts the engine up another 12mm with the adapter plate. Its all definitely possible but you may have quite a bit of glass work to do before it sits happily in the space. And then there’s the propellers to consider, fixed is a lot of drag and folding/feathering is quite expensive. You might also entertain the idea of increasing the fuel tank capacity.
Pete.

[Sailmonkey]

As far as value……..

Do you feel the boat is woefully underpowered now?

When I’m browsing boats for sale, I cruise right past boats that have had these sort of changes made. Even though you claim the 100kg extra weight is t a problem, it is. Then I question if the boat sails so poorly as to require these larger engines. Then I wonder about all of the other changes that were made that don’t improve the sailing ability.

So resale is also more difficult.

[tkeithlu]

Quote: "What I am trying to gauge is whether I will be adding value or not"

It is difficult to imagine your actually coming out ahead at sale time with this conversion. You'll have to spend a LOT of money, and then face the suspicion on the part of buyers that you have butchered the boat, added weight, and added running cost.

[psahd]

Thanks for the all the input guys - really good insight. I have decided along with all of you that it is an idea to install the isuzu's, but it is a really sh*&y idea!

My boat has two perfect motors. FWIW, the reason for thinking about it in the first place was to try and help another sailor that has recently (2 weeks) a Prout Snowgoose. On his maiden voyage as owner, he seized his port Penta MD2020. His starboard Nanni 20HP is smoking badly. It was an idea for me assist him by passing on my 3GM30's with saildrives and do the Isuzu conversion. But I do see that the reason for going down this path was very flawed...

Much Appreciated
Peter