I have heard mixed reports about Mercruisers and was wondering if anyone is familiar with these engines? They are on an outdrive boat and are about there to four years old.
Any thoughts gratefully recieved.
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Thread: Cummins Mercruiser 4.2L 270HP
21-01-12, 09:37 #1
Cummins Mercruiser 4.2L 270HP
21-01-12, 15:05 #2Registered User
Location : midlands boat Hamble
- Join Date
- Apr 2007
I know ill get some stick over this but there not the greatest motor in the world, id go for a green motor if its available unless the boats 20k cheaper than its equivalent green motor model.
Its a VM based unit with bosch electronic controlled pump.
21-01-12, 15:39 #3
I'd say any other. Green, blue, white...
Some believe Merc 4.2 is based on Toyota's legendary base engine as is the case with Yanmar and Nanni, but it is not.
VM have done some fine inventions and produced engines or technology for several of the big ones (Mercedes, BMW etc.) but their marine history isn't outstanding.
21-01-12, 16:32 #4
Ive had a couple of 4.2 L D300 for 5-6 years.
Very pleasing to own (95% the time), smoke free, smooth and economical.
Many were sold with 6 years warranty on major parts which could take away most the worry of buying second hand..
21-01-12, 18:42 #5Registered User
Location : midlands boat Hamble
- Join Date
- Apr 2007
21-01-12, 18:50 #6
Thanks guys, some interesting stuff.
Playing devils advocate, there are lots of negative comments about these engines but with the exception of the mild steel sump corroding in two years no examples of issues and the only comment from an owner is actually quite positive.
Anyone got any examples of problems or design flaws?
22-01-12, 05:48 #7
For your information and entertainment the enthusiasts at TunnelBoreSix, who strive to supply parts for these engines, tell:
Early design changes to the modern diesel came out of ‘The Land of Ferrari and Lamborghini ‘ in Northern Italy. VM Motori, located there in the town of Cento, is a prime manufacturer of diesel engines. [ VM is currently owner by Roger Penske and GM ].
Applying the ‘tunnel bore design’ to a diesel engine came out of VM Motori’s engineering department in 1977. The development of this design was lead by VM R & D chief engineer, Ivo Maini. For fun, Maini ‘tricked up’ a tunnel bore six with amongst other things, a BMW gasoline fuel injection manifold and then installed his ‘Hot Rod’ diesel in a boat. In his diesel powered Hydro-plane he held world speed records for many years.
Also in 1977, BMW having manufactured marine engines since 1919, fired up their new BMW Marine GmbH division. To offer a full range of products, diesel engines were needed. With no suitable BMW diesel made ‘in-house’ BMW approached two relatively local engine makers; Hatz on the German – Austrian border and VM Motori in Northern Italy.
VM’s ‘ Tunnel Bore Six ‘ became the base upon which the BMW 6 cylinder marine diesels were built. VM supplied industrial engine blocks to the BMW Marine engine plant in Belgium. Here BMW’s engineers marinized them, producing the first BMW D150's. All the marine hardware and accessories’ were of BMW design. Engines were offered in two configurations, with a transmission or with BMW’s new Z-drive stern drives.
Engineering work never stops. Soon major cooling components were redesigned, intake air cooling ( inter-cooling ) was added and a D190 with 162 HP was introduced. Eventually the D190 was improved and became the D636. VM supplied a new 5 cylinder block and BMW introduced the 5 cylinder D530 to it’s product line.
Suddenly in December 1987, with little warning, BMW closed its Marine Division. The Belgium plant was sold to the American competitor, Mercury Marine. The paint guns no longer held BMW Silver, but Mercury Black, and the ‘BMW Diesels’ with logos removed and decals added continued rolling out of the Belgium plant. The D636 became a 636D-TA. The D530 became the 530D-TA. Soon Mercury changed the 636D-TA to the D219AC. The 530D-TA became the D183TURBO AC
Meanwhile in Italy, VM bored and stroked the 3.6 litre, increasing the displacement to 4.2 litres. VM also began building their own line of marine engines. In 1993 Mercury entered a new agreement with VM and new 4.2 litre engines were shipped to Mercury Belgium. Many of the VM marine accessories were shared with Mercury.
Again VM redesigned the early 4.2's (D254) and introduced the new MD706MI. The changes were primarily to the cooling system. In turn, Mercury replaced their D254 with the D4.2L/220 IDI and transferred the assembly of Mercury’s diesels to engines was completed at VM in Italy.
On February 14, 2002 Mercury Marine and Cummins Engine formed the Cummins, Mercury Distribution partnership. Today ‘CMD’ is primarily under Cummins management, and utilizes Cummins’s world-wide distribution network. Despite the ‘BMW Diesels’ as they are still referred to as, not being a Cummins product, Cummins continues to support and sell the D4.2 series engines. Mercury, both in Fond Du Lac and in Belgium continue with parts support.
Over the years the original BMW D150 ‘tunnel bore six’ marine engine has been greatly refined and improved. Indirect Injection (IDI) combustion gave way to Direct Injection (DI) and electronic ‘D-Tronic’ control of the injection pump was introduced. In the early 2000's diesel engine technology leapt ahead and horsepower outputs increased significantly. This progressed from 136 HP to 165 HP to 200 HP to 220 HP to 230 HP to 250 HP to 270 HP to 300 HP to 350 HP, proving that VM’s creation of this tunnel bore design diesel engine was a landmark.
As these engines age, parts become harder and harder to find. Owners, Marinas and Mechanics working on these engines were finding current and obsolete parts available from V12 Engineering via the website. Many of the original BMW Marine Parts are common to the latest CMD D4.2 engines. The best example of this is the new ‘MLS’ cylinder head gaskets, cylinder head bolts, etc. fit all models. We are now the source for ‘In Frame’ engine overhaul kits for all 3.6 and 4.2 litre engines. These ‘KITS’ include all bearings, pistons, rings, liners, seals, gaskets and o-rings to overhaul your engine. V12 Engineering ships parts world wide.
Aliases for the engine:
Mercruiser D254, D4.2L/220 - 300 D-Tronic
Cummins CMD 4.2 EI 300 - 350
VM HR.H 694, MR706 LS / LH / LX
In 2003, Penske Corporation purchased a 51% stake in VM Motori; in 2007, Penske bought the remaining 49% from DaimlerChrysler and subsequently sold 50% of it to General Motors. As of 2007, both deals were awaiting European regulatory approval and the value of the deal was not known.
In September 2008, GAZ Group announced plans to purchase a 50% stake from Penske Corp. but ultimately cancelled them in February 2009. January 11, 2011 Italian newspaper Corriere della Sera published news that Fiat S.p.A. is about to purchase 50% stake from Penske. In February 11 Fiat Powertrain Technologies confirmed it has bought the 50 percent stake.
Last edited by Spi D; 22-01-12 at 05:52.
21-01-12, 17:24 #8
21-01-12, 17:58 #9
VM are an Italian maker, ok engines on the road, disco's, BMW, Omega 2.5, but in a boat? no way, my mate had a new one and in 2 years the sump had rusted, imagine that a mild steel sump on a boat engine. Was it re-engined because the original engines were the same??
21-01-12, 18:15 #10
in 1947, the company produced the first Italian air-cooled diesel engine with direct injection.
In 1964 the company introduced entire new families of air-cooled diesel engines for fishing boats and the industrial machine markets.
1974 saw the introduction of a new series of high-speed (4200 rpm) HR, pre-combustion chamber, water-cooled, turbocharged engines.
The Alfa Romeo Alfetta, produced in Arese, rolled off the line with a VM Motori engine under the bonnet in 1979, signaling VM's move to the OEM automotive market.
During the 1980s British Leyland chose VM engines as the smoothest, most petrol-like units available for diesel models of their Range Rover and Rover SD1; the choice continued with the later Rover 800.
The after-cooled, electronic-combustion, "Turbotronic" engine was unveiled in 1990. It was supplied to Alfa Romeo, Chrysler, Ford, General Motors, and Rover.
In 1995, when OEM automotive sales accounted for 75% of income. A major deal with Chrysler saw agreements to supply engines for their Jeep Cherokee and Voyager (2.5-litre) models.
VM Motori's 2.8-litre common rail turbodiesel engine was chosen for the Jeep Liberty CRD. The 2008 and later Chrysler Grand Voyager and 2012 model year Chevrolet Colorado That sale in Thailand is also fitted with the VM 2.8-litre (R428) engine.
GM Daewoo has licensed the 1.5-litre and 2.0-litre common rail engine designs, and built a dedicated engine plant, which started production 2006. The 2.0 L diesel is used in the Chevrolet Captiva/Opel Antara/Daewoo Winstrom, the Chevrolet Optra/Daewoo Lacetti, the Chevrolet Cruze and the Chevrolet Epica/Daewoo Tosca.
The latest vehicle to benefit from a 2.5 L VM Motori diesel engine is the purpose-built LTI (London Taxis International) London style taxicab - the TX4 is the first of the TX range of taxis to include a VM Motori engine.
The company is also selling its products to off-highway applications, such as marine and defense. MTU Friedrichshafen, a German diesel engine manufacturer, holds the exclusive sales rights for VM Motori off-highway engines outside of Italy.
In June 2010 VM Motori started the production of the new 2.8L 4-cylinder Euro 5 engine to power the 2011MY Jeep Wrangler, 2011MY Jeep Cherokee . The A428 has a maximum power of 200 PS (147 kW; 197 hp) and a torque of 460 N·m (340 lb·ft) at 1800 rpm. On the manual version of the Jeep Wrangler the A428 features the Stop/Start system to reduce the CO2 emissions.
In January 2011, VM Motori launched its brand new engine 3.0L V6. With 241 CV and 550 N·m (410 lb·ft) the A630 is among the best diesel engines in its class. As result of the collaboration with Fiat Powertrain Technologies the engine features the Multijet2 technology for improved performance, fuel economy and NVH. The first application of the 3.0L V6 is the 2011MY Grand Cherokee.