• Easily used by ships maintenance staff right out of the box

  • Instant indication of condition for motor bearings, gears, compressors, slewing rings, hoists, winches...

  • Plan maintenance and have the spares available on time. Minimise off-hire and demurrage.
Quick Contact
This question is for testing whether you are a human visitor and to prevent automated spam submissions.
Enter the characters shown in the image.

Carbon Residue in Fuel Oils

Carbon residueThe carbon residue of a fuel is the tendency of carbon deposits to form under high temperature in an inert atmosphere. It is known that the correlation between carbon residue and diesel engine performance is poor. However, in the absence of any other parameter, this property is included in fuel specifications, indicating the carbonaceous deposit-forming tendencies of the fuel. Many factors can affect the combustion process in diesel engines, including engine loading, engine tuning and the ignition qualities of the fuel which all have an effect on the deposit tendencies of a particular fuel.

The carbon residue value of a fuel depends on the refinery processes employed in its manufacture. For straight run fuels, the value is typically 10 - 12% m/m, while for fuels from secondary refining processing the value depends on the severity of the processes applied. In some areas it can be as high as 20% m/m.

Modern engines are tolerant to a wide range of MCR valves. However, some older engines, typically of the 1970s, are such that difficulties may be experienced burning fuels with an MCR greater than 12% m/m, especially at low loads. Above this level, there is likely to be increased carbonaceous deposit, which will affect the performance of the engine. Operational experience has shown that the present generation of large, medium and slow speed engines designed for residual fuel can tolerate a wide range of MCR values without any adverse effect.


  • >20% High; may be problematic and cause increased fouling
  • ~ 13% Current global average

Injector nozzles can become fouled using high MCR fuel. Careful control of nozzle cooling temperature can help reduce this.


Off-line Bunker Fuel

Latest News

Parker Kittiwake Launches New CAT Fines Test Kit
Test kit detects catalytic fines to prevent irreparable damage to fuel pumps, injectors, piston ring... Read More...
Switching Fuel Oil and the Risk of Loss of Propulsion
Nearly nine months have passed since the 0.1% sulphur limit for marine fuels in designated Emissions... Read More...
Measuring Ferrous Wear: the FWM vs. the Analex fdMplus
When it comes to detecting and analysing machine wear, testing for ferrous density – the prese... Read More...