Routine Maintenance on Diesel Engines – Is it cost effective?

Written By:  cws-admin April 10, 2016 at 3:36 pm

“Maintenance Works” – A special communication for the customers of Staten Island Yacht Sales

Absolutely! Neglect can lead to breakdown and failures. Preventative maintenance is necessary in order to limit your potential for future huge & expensive problems. If we view each one of the engine’s systems separately we see what areas need preventative maintenance.


Small fuel leaks don’t go away and could be a precursor to an even bigger problem. Fuel leaks could be a sign that a hard fuel line could be ready to break or a rubber hose is degraded and ready to burst. Other fuel system troubles can come from neglected fuel filters. You probably change the primary fuel filters regularly but not the secondary filters because they are too expensive or time consuming. Remember, the sea towing company isn’t free either. You are statistically more at risk of plugging a fuel filter or line during rough seas. Make sure you follow a strict maintenance schedule for replacing fuel filters and always use OEM (original equipment manufacturer) filters and parts!


Dirty air filters cause marine diesel engines to run dirtier and waste fuel. Loss of clean air for combustion can also lead to higher internal engine operating temperatures and reduce engine life. We have observed a paper type air filter that got wet and then went through the turbocharger and blocked the inlet side of the charge air cooler. That $80.00 air filter failure cost a few thousand dollars in labor and a new turbocharger. A routine replacement schedule for the air filter would have prevented that “big” job!


Check the level and condition of the coolant in the main engines and generator (if equipped). Look for external leaks around filling caps, hose clamps, air bleeding points and signs of chafing or weak hoses. Follow the one year/one impeller rule. We recently removed an impeller from a spare sea water pump that was on a customer’s boat for 2 years. The impeller blades had taken the shape of the surrounding housing. It was an impressive sight but wouldn’t have been a reliable piece to depend on for sea water flow! Check belts which drive circulating pumps or sea water pumps (if equipped). Rubber parts such as belts and hoses suffer the effects of high engine room temperatures much more than automotive belts. If a belt shows glazing, cracks or hardness than it should be changed. Belt tension pulleys have failed causing belt breakage and severely overheated engines and failures. Some of the smallest components can cause the biggest headaches!


Oil is the life blood of any engine. Engines use oil for two main purposes. Oil lubricates the finely machined surfaces but it also offers heat transfer away from hot metal parts. Oil operates in extreme temperatures and can break down so the cleaner the better! Follow the type and weight recommended for your application. Many new marine diesel engines mandate the use of fully synthetic diesel approved oil. The engine operator’s manual will provide the information to help you choose oil for the area or climate your engines operate in. The engines should be frequently inspected for leaks. Oil leaks should be addressed if discovered. Can you tell the difference between a nuisance (small yet persistent) oil leak and a potential catastrophic (small with huge potential) oil leak. Many oil related engine failures began as small oil leaks which could have been corrected before maturing into catastrophic leaks!


Make certain your batteries and charging system are in good condition. Low voltage can cause high amperage loads which can shorten component life and cause breakdowns. Newer marine diesel engines require D.C. voltage to power the ECU (engine’s brain) all the sensors and engine monitoring displays. Change your batteries according to the boat builder’s recommendations or follow our (every two year) recommendation.

Contact us today to schedule your boat service appointment! 718.984.7676

This article is complements of Scott Marine Power – our on-site engine specialists! Scott Marine Power, located in Ft. Lauderdale, FL and New York City, NY, is an authorized dealer for MAN Engine and Yanmar marine diesel engines, MAS Power and Phasor marine generators, Bosch Rexroth Controls and Walker Airsep Systems. For more information visit