Genuine VM Coolant Pump
VM part # 1 520 2030
Genuine VM Cylinder Liner
VM part # 2 024 0060 HR.H 692 3.6 Liter
VM part # 2 024 2006 HR.H 694 4.2 Liter
VM part # 2 024 2038 MR706 4.2 Liter
Genuine VM Cynlinder Heads
VM part # 1 035 2025 (tangental glow plug)
VM part # 1 035 2028 (4.2 Liter 'IDI')
Stainless Exhaust Elbow
Mercruiser part # 8017633259
Mercruiser part # 801763206
BMW part # 1811 1763 206
Exhaust Gaskets 'IDI' engines
VM part # 2 202 0146 A
Mercruiser part # 27-801333449
BMW part # 1162 1333 449
History of the BMW Tunnel Bore Six
In the world of engines, diesels have been the workhorses, the Clydesdales, pulling plows, freight trains, farm and highway tractors and pushing ocean liners.
Today, engine makers BMW, VM Motori and others are changing that. Diesel engines are being hopped up, 'tuned' and re-designed using technologies common in gasoline engines. Overhead camshafts, 4 valve heads, high pressure fuel injection and computerized engine management systems are common on today's diesel engines.
An early design change to the modern diesel came out of 'The Land of Ferrari and Lamborghini' 35 years ago.
VM Motori, located in the small town of Cento, is a manufacturer of diesel engines.
In the 1970s VM engineers applied the 'tunnel bore design' to a diesel engine. The development of this design was lead by VM's new chief engineer of R & D, Ivo Maini. For fun, Maini 'tricked up' a new tunnel bore six with an intake manifold from a BMW M30 engine. He installed it in his boat. His diesel powered Hydro-plane held world speed records for many years.
BMW started the manufacture of marine engines in 1919. In 1977 they fired up their BMW Marine GmbH division. In competition with Volvo Penta, diesel engines were needed. BMW had no 'in-house' diesels, so they approached two engine makers near them; Hatz on the German - Austrian border and VM Motori over the Alps in Northern Italy.
VM’s HR.H 692 'Tunnel Bore Six' became the base upon which the BMW 6 cylinder marine diesels were built. VM supplied long block HR.H 692 industrial engines to BMW's Marine engine plant in Belgium. BMW's engineers marinized them. The result was BMW's D150.
An engineer's work never stops. Major cooling components were redesigned, intake air cooling (inter-cooling) was added and the 162 HP BMW D190 came to life. Next the D190 was improved and to become the D636. Next, VM supplied an HR.H 592 5 cylinder block and the BMW D530 was born and added to the product line. The HR.H 692 was a modular engine with individual cylinder heads. VM introduced their own 4 cylinder marine version of the HRH 492, a 4 cylinder with a 92 mm bore.
In December 1987 BMW closed its Marine Division and sold the Belgium plant with inventories to the American competitor, Mercury Marine. The paint guns no longer held BMW Silver, but Mercury Black, and the 'BMW Diesels', now black Mercruisers rolled off the Belgium production line. The BMW D636 became a Mercruiser 636D-TA. The D530 became the 530D-TA.
Meanwhile in Italy, the VM Motori engineers 'bored and stroked' the 3.6 litre out to 4.2 litre engine. Primarily for the Italian market, VM began building their own line of marine engines, the first being the D254.
In 1993 Mercury...
VM took over the manufacturing of the Mercruiser diesel engines. Many VM Marine parts and accessories are shared with Mercury.
Mercury replaced their D254 with the D4.2L/220 IDI and transferred the assembly of Mercury's diesels to VM in Italy.
To date, all VM 4.2 engines were indirection injection, 'IDI', glow plug engines.
VM's engineers again improved their favourite engine. The 4.2's were now direct injected with Bosch electronics.
VM's latest MR700 engines, now painted white became the CMD QSD 4.2s.
The most recent changes came in 2006 with the upgrade to 'common rail' fuel system - again from Germany's Bosch.
On February 14, 2002 Mercury Marine and Cummins Engine formed the Cummins, Mercury Distribution (CMD) partnership. 'CMD' was primarily under Cummins management, utilizing Cummins's world-wide distribution network. Still, inside Mercury, these VM made engines were and are referred to as the 'BMW' diesels.
The Cummins Mercruiser partnership ended in 2013. Mercury took back the sales and marketing of the VM MR 700 engines.
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 are 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 worldwide.