International Dredging Review

International Dredging Review

Dredge maintenance―and in particular marine engine marine auxiliary engine and marine generator set maintenance―is crucial to ensuring a long life in the water and long-term company viability.

Official guidelines for maintenance are often not clear on marine maintenance procedures. The Port State Inspections Pocket Checklist from Class NK a marine classification organization (and an entity whose mission includes promoting the safety of vessels their crews and the marine environment) lists only an updated oil record book and working oil filtering equipment as the notable engine maintenance components of a port inspection.

Worldwide Power Products (WPP) which maintains an extensive fleet of rental equipment and performs contract maintenance for hundreds of companies offers some suggestions to help dredge owners and operators ensure their maintenance practices give them the maximum life out of their equipment and improve crew safety and ROI.

Due to space limitations this article is unable to discuss the full range of maintenance procedures that are important to good engine condition. Overall regular condition checks for three fluids―oil coolant and fuel―are vital to the health of the engine. This article will describe oil checks only and recommends that operators refer to their equipment manuals for descriptions of important coolant tests.

Double check maintenance routines for each vessel’s main engines auxiliary engines and generator sets. Dredging companies should perform the required engine and generator set maintenance (including changing oil oil filters and fuel filters) based on fuel consumption or service hours first and on calendar intervals last. Authorized operators should perform daily and weekly maintenance checks and procedures. Authorized company or dealer personnel should perform the maintenance required for all other intervals.

Maintenance should include regular oil analysis of all marine engines at oil change intervals. This can keep vessel operators informed as to whether an engine’s oil is doing its job of protecting the engine. Oil analysis helps with early problem detection reduces repair costs and reduces the impact of downtime. Additional tests identify contamination by fuel water and/or coolant and there are four main types of analysis for oil:

• An oil cleanliness analysis detects metallic and non-metallic debris from wear and outside sources. This test which uses a particle count test to determine the results can detect potential failures that wear rate analysis alone cannot identify.

• An oil contamination analysis uses a spectrometer to detect silicon which indicates the intrusion of dirt into the engine.

• An oil condition analysis uses infrared waves to measure loss of oil’s lubricating abilities. With this information technicians can verify whether or not the oil is performing up to specification―and identify the level of oil deterioration if any caused by oxidation or nitration.

• A wear rate analysis tracks component wear by detecting identifying and assessing the amount and type of metal wear elements in the oil. Maintenance records should also track the rate at which worn metal particles increase from sample to sample. This helps determine wear rate trends for bearings (copper/zinc) liners (iron) and rings (chromium).

Battery testing using a refractometer gives dredge operators a good indication of battery condition and how the battery will perform under heavy load over a period of time.

Check for worn or improperly operating parts and either replace them on the spot or schedule them to be replaced as soon as possible. Any parts replaced or scheduled for replacement should be noted on the inspection report (see the next item) including the quantity part number and description. If follow-up is needed there should be a mechanism for ensuring it is done.

A detailed maintenance report encourages thorough practices whereas inadequate ones make it easier for items to be skipped. In addition to listing all the best practices for engine inspection and maintenance service―from checking air filtration to inspecting wiring harnesses and connections―the checklist should provide an area for workers to record data from the current inspection.

Maintenance reports should also specify that the crew record important measurements. The lead technician should be required to sign and date the report and provide his or her name for quality-control monitoring purposes.

Implementing a computerized maintenance management program to track and manage engine (and other equipment) maintenance will pay for itself in a few years at most.

Furthermore advances in ship-to-shore communications―specifically the availability of persistent wireless Internet connections via satellite―enable land-based home offices and other company facilities to monitor maintenance data remotely. It also helps avoid wasted labor and facilitates regulatory compliance.

About the Author: Ron Bernucho is inside sales engineer for Worldwide Power Products an independent company based in Houston Texas that specializes in power generation equipment buying and selling new and used generator sets and engines worldwide.

For more information visit