Mercury Marine adopts CGI

Reports are emerging from Mercury Marine of a 2-litre marine diesel engine with a cylinder block of vermicular graphite iron or GGV.

The initials GGV are derived from the German Gusseisen mit Vermiculargrphit – a term used in non-English speaking countries. In countries where English is spoken it is called compacted graphite iron CGI. 

As readers know, CGI is a material gaining in applications where greater strength or lower weight than offered by regular grey iron is required.

Mercury Marine, with headquarters in Fond du Lac, Wisconsin, says the TDI engine block is fabricated from Vermicular Graphite Casting (VGC), which it says has twice the strength of grey iron and most of its attributes, but is 5 to 10 per cent lighter. The end result is low weight, high strength, and maximum heat transfer for optimum cooling.

Mercury then adds that TDI is a registered trademark of Volkswagen AG). Mercury uses other diesels from the VW group, including the Audi 4.2-litre V8 engine which also has a CGI cylinder block.

Mercury notes that the low weight of these diesels results in best-in-class power-to-weight ratio. Combined with great low-end torque, the end result is crowd-pleasing hole shot, great acceleration, low planing times and ultra-smooth performance.

Mercury explains that DI technology uses injectors to spray diesel fuel atomized at 26,000 lb/in2 directly into the main combustion chamber of each cylinder. This process optimizes fuel efficiency and minimizes emissions, along with engine Noise, Vibration and Harshness (NVH) for an enjoyable boating experience.

The engine has an output of 172.4 bhp (127 kW) and a weight of 582 lb (264 kg).

Mercury gives the bore and stroke of 83 mm x 92 mm.

VW’s EA288 2-itre diesel engine which appears in the Golf has a bore of 81mm and a stroke of 95.5mm. Power output is 150bhp (110 kW) and a torque of 320Nm. in-line diesel engines.
COMMENT. Mercury Marine's annual sales of 2-litre TDI engine must be quite small compared with Volkswagen's output of 2-litre TDI engines, so this activity in the US could be a welcome opportunity for VW's engineers to 'get their hands wet' with the application of CGI to four-cylinder in-line diesel engines - if they have not done so already.