MAN 1035hp 18.3lt V-10 D 2840 LE 403EDC

Weighing in at just 1560kg in bobtail form (sans gearbox), MAN's new 1035hp 18.3lt V-10 D 2840 LE 403EDC diesel offers excellent performance and torque in a compact package.

To reveal how light the V-10 is for its output, it develops 63% more horsepower than the electronically-managed Cummins QSM11 - yet weighs only 39% more.  At a 'light duty' rating for recreational and light commercial vessels, the V-10 develops 1035hp at 2300rpm - yet at these revs, still provides 91% of maximum torque.  And at the maximum torque band of 1800-1900rpm, where the MAN V-10 develops a massive 3500Nm of torque, the output is still 840-900hp!

The V-10 is in the mid-range of the German manufacturer's pushrod direct-injection 90° Vee-block diesels, from the 670hp V-eight D 2848 LE 401 to the 1280hp V-12 D 2842 LE 404EDC.  In twin-engine installations, the V-10 suits planing hulls in the 16-17m range and develops 5% more power and 1% more torque than the V-12 D 2842 LE 401 with fixed fuel-injection timing (which is also 9% heavier).

Compared to its electronically-managed 21.9lt V-12 404EDC counterpart, the V-10 develops 19% less power but only 14% less torque, although the V-12 does have a broader torque band.

I've long been a fan of engines having an odd number of cylinders or multiples of such.
Five-cylinder engines are an effective compromise between more fuel-efficient fours and thirstier sixes - and this all works with a V-10.  In each bank of cylinders no two pistons are ever at the same level, as with fours and sixes which use multiples of two.  Subsequently, all the pistons in an odd-numbered bank help to even out the firing and exhaust cycles.

The first ship I served on in the Merchant Navy had a seven-cylinder Sulzer 7RND76 diesel, which was better balanced than straight-six and eight Sulzer's of the same piston displacement.

The V-10 slots in nicely for length between its V-eight and V-12 counterparts.  In bobtail form it's 1637mm long, only 150 more than the V-eight block but 173 less than the V-12.  From the flywheel housing to forward end of the engine it's only 1334mm.  It's 1230mm wide and 1194mm tall including a deep oil pan.

Compared to an in-line engine the LE 403EDC is 82mm shorter than Yanmar's 17lt diesel and 148mm lower, but does lose out in width where this measurement is 217mm greater.  Through the use of an 'Electronic Diesel Control' (EDC) system, MAN has also kept fuel consumption at reasonable levels for the engine's output.  Based on a standard propeller power curve at the maximum torque band, the V-10 consumes about 120lt/hr (similar to a 350hp petrol V-eight!), rising to 212 at Wide Open Throttle.


Man Torque

To reveal just how effectively the EDC system manages the V-10 (compared to the V-10 D 2840 LE401 which has fixed fuel-injection timing), the 403EDC develops 28% more power and 25% more torque at the same revs while specific fuel consumption drops by 2% - yet the bobtail weight is only 3% greater.  The EDC monitors both the engine and gearbox via a series of sensors, which compare the actual figures with specified values.  For example, the main parameters include what conventional gauges would show (ie: engine revs and temperature, oil pressure and alternator voltage).

However, MAN's EDC goes a lot further and covers engine coolant and oil levels, coolant, charge air (of the intercooler), and fuel and gearbox oil temperatures.  Optional sensors cover coolant flow rate and fuel pressure and leakage from injector pipes.  The MAN control panel has a series of green and red lights and a test function with reset facility.
When the engine is running a green light comes on, but all other functions (such as engine overspeed or reduced speed) light up in bright red.  Under these or any other abnormal operating situations, the EDC reduces fuel flow to the injectors and, consequently, speed is reduced.

The MAN EDC system also eliminates conventional control cables in favour of easy-to-service wiring, thus ensuring easier installation and preventing engine vibration and noise from reaching the helm area.  Each bank of cylinders has its own turbocharger with dry air intake filter and the two-stage intercooler has a combustion chamber air pre-heat.  When the engine is idling, air is pre-heated to reduce the formation of white exhaust smoke.  But under load and/or depending on charge air pressure, the air is then cooled for maximum density and combustion efficiency.  To increase intercooler efficiency, the sea-water passes through this before reaching the engine heat exchanger.