Vessel Make: Luhrs 32
Vessel Weight: 10 Tonne Heavy Ship
Old Engine 2 x Yanmar 6LY3-UTP
New Engine: 2 x FPT NEF 400 (N60 ENT M40)
New Engine Power: 2 x 400Hp @ 3000rpm
Vessel Gearbox: ZF 85A 2.0:1
Vessel Cruise Speed: 20kn @ 2600rpm
Vessel Top Speed: 25kn @ 2000rpm

A great fishing boat for the North West. The Luhrs 32 is a very beamy vessel for only 32ft in length.


Unfortunately, the Yanmar engines suffered a fuel contamination failure, and as a result, the decision was made by the client to buy new. His choice, the FPT NEF 400 Marine Engines!

With very similar displacement and slightly lighter, the NEF 400 offered an excellent fitment into a quite tight engine room.


One significant advantage was being able to reuse the existing ZF 85A gearboxes which unbolted off the Yanmar engines and straight onto the NEF 400s. This significantly reduced installation costs, as the rear mounts were bolted to the gearboxes, meaning only the front engine mounts needed modification to allow the NEFs to fit into the vessel.

Electrics for the engine were set to 12V, as opposed to the 24V option so that the existing vessel battery system at 12V could be reused.


For throttle and gearbox control the ZF 85A gearboxes were electronically actuated with 12V solenoids. The easiest solution was for a new Flexball throttle system to be supplied, which allows for connection to the existing ZF solenoids as well as electronic input via CANBus to the engines. The Flexball are fantastic because they also offer a “sync” function so both engines can be controlled off one lever so the rpm matches exactly the same.


At the 400Hp pleasure duty range, the engines performed exceptionally well at sea trial. As expected, the speeds of the vessel did not vary greatly as horsepower between new and old engines are similar. The Yanmar engines achieved 19kn cruise @ 2600rpm, the NEF achieved 20kn @ 2600rpm cruise. However the difference is the NEF 400 only rev to 3000rpm whereas the 6LY3 rev to 3300rpm. The propellers have not been adjusted, so the NEF achieved over 3000rpm. Therefore meaning the vessel is currently underpropped and with adjustment would allow for increased cruise speed at lower rpm.


The FPT Compact 5” Deluxe Control Panel was chosen for instrumentation, which offers excellent engine monitoring and fault diagnostics for the NEF 400s.

The NEF is an excellent and compact engine, specifically with its compact design of cooling system. Perfect for any application where space is tight, like this Luhrs 32.

Overall an excellent repower with focus on reusing as many components as possible, whilst ensuring reliability, adequate cruise speed and low fuel consumption.

Please get in touch with THT for your next repower.