Engine replacement Nord Havn 46

[james247]

Originally Posted by Laura Foster

We have a John Deere 6068 (TO6068D) by Lugger in a Nord Havn 46. We have to replace the engine. Does anyone know of a comparable engine to the John Deere? Any experience with replacing with another engine? Any advice would be helpful! Thanks

In the Philippines the most common Diesel engine is likely the Kubota
It is the backbone for several marine engines
The cost of the engine and the marinisation kit will likely be quite low by comparison to others
Strongly suggest you look into this possibility

[Moon rise]

Hi ya.
just up the road from Zekes a bit is a yard run by a guy called Tim, he imports engines from australia for the cats he builds go talk to him.
I need a engine for a 46 ft yacht as well so very much interest as to how you get on

[bdbcat]

Kenomac...

Thread drift here...

It is all about horsepower produced (RPM x torque), which is almost linearly related to fuel consumption over the range we are interested in.
For your boat, if you carefully measure the fuel consumption rate at 1200 RPM, you would probably be surprised how low the power requirement actually is. I'd guess 50 HP, or less. We install higher horsepower engines so that we have a reserve for tough conditions, and generally don't mind carrying the extra weight in the interest of reliability and safety.

The super high power ratings from common blocks are most often used in high speed planing type hulls. And the anecdotal stories of blown sport-fisher engines after a few thousand hours are well known....


Hope this helps
Dave

[Terra Nova]

I would replace it with an identical new engine or else a Caterpillar.

[Kenomac]

Originally Posted by bdbcat

Kenomac...

Thread drift here...

It is all about horsepower produced (RPM x torque), which is almost linearly related to fuel consumption over the range we are interested in.
For your boat, if you carefully measure the fuel consumption rate at 1200 RPM, you would probably be surprised how low the power requirement actually is. I'd guess 50 HP, or less. We install higher horsepower engines so that we have a reserve for tough conditions, and generally don't mind carrying the extra weight in the interest of reliability and safety.

The super high power ratings from common blocks are most often used in high speed planing type hulls. And the anecdotal stories of blown sport-fisher engines after a few thousand hours are well known....


Hope this helps
Dave

Yes it does, thanks much to both of you for explianing things.

[a64pilot]

Originally Posted by DotDun

IMO, derating is done to allow the same engine to fill a broader set of requirements. If a new engine design was required for every application, cost would be significantly higher. e.g., the Yanmar 3TNE in my genset is available with various fuel options creating 12hp - 30hp, depending on application, or the Suzuki 20hp outboard on my dinghy...same engine for 9.9hp and 15hp, just alter the fuel system.

This is exactly why, for example the Venerable IO-540 Lycoming aircraft engine is available in variants from 235 to 300+ HP. The 235 has a reputation of being a very long lasting motor.

Very often they are derated by specifying lower RPM as being redline, lower Max RPM, lower Max HP.
Wear on an engine isn't linear, meaning a 20% increase in RPM is more likely to double the wear as opposed to increasing it by 20%.
Wear follows more closely the total energy in the moving parts and we know that velocity increases energy much more than mass, although of course it's not always that simple, a long stroke motor may have a higher Piston speed than a higher revving short stroke

[Pelagic]

I think the most important consideration for OP is to make sure the "ergonomics" of a different make engine and rating takes into account all the ancillary equipment (alternators/PTO pulleys/instruments/ controls/ reduction gear) are compatible.

Confirm they all fit and can be serviced without too much re-engineering.
Especially in the Philippines!

Sometimes replacing with identical is the smart decision.

[James S]

Originally Posted by Pelagic

I think the most important consideration for OP is to make sure the "ergonomics" of a different make engine and rating takes into account all the ancillary equipment (alternators/PTO pulleys/instruments/ controls/ reduction gear) are compatible.

Confirm they all fit and can be serviced without too much re-engineering.
Especially in the Philippines!

Sometimes replacing with identical is the smart decision.

I would think this would be the easiest install for sure...

[Singleprop]

I would go for same engine (new or remanufactured) as it will be a direct replacement....

Here's an article about re-powering.

http://frontierpower.com/wp-content/...rint_deere.pdf