Wednesday, May 30, 2012

Diesel Marine Engine Tips

Captain John shares his diesel marine engine tips for a trouble-free season...

Guest blog by Captain John
Captain John Jamieson, a regular contributor to the Daily Boater, is author of Seamanship Secrets and publisher of the popular boating education website

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Like a thief in the night it creeps through your engine lines and works its way past the gate guards. Then it slides, slips, and slithers like a rattler into the belly of your engine. Waiting. Resting.

And as soon as you push the starter button, it awakens and begins its relentless, merciless, life-sucking destruction. Don't let this happen to you this sailing season. Follow these easy 1-2-3 steps to combat this enemy once and for all!

World famous cruising sailor and engine guru Nigel Calder has - I believe - the perfect title for a chapter in his book "Marine Diesel Engines". In five simple words, he describes the mantra that any sailor with any engine on earth should heed: Cleanliness Is Next to Godliness.

That monster we are talking about goes by many names - dirt, dust, grime - but they all are guaranteed to do one thing; cause you grief, big money, and lots unreliability with your small diesel engine (or outboard for that matter).

All engines need but three "clean" things to operate like a top: clean air, clean fuel, and clean oil.

Keep Your Air Filters Clog-Free!
Clean air gives you good compression. Lose compression from a clogged, dirty, dusty air filter and you lose power and starting you engine becomes harder and harder. Black smoke from the exhaust signals unburned fuel.

Often forgotten, that air filter on the side of your engine needs lots of attention. It can be hard to pick out, but it often resembles a miniature hair-dryer. Change air filters at least once a year or as your environment changes. Do this even if the filter looks clean after several months. This will ensure easy starting and proper combustion to give you good, reliable power.

Keep Your Fuel Squeaky Clean!
90% of all problems with all engines are related to contaminated fuel. Water, bacteria, and dirt are the major enemies of fuel. Ignore these enemies at your peril. Water in a fuel tank encourages bacteria growth.

After all, it’s dark in that tank, which makes it the perfect "petri-dish" for engine killing microbes to grow. Dirt kills engines faster. One speck that makes its way past a fuel filter can damage your costly injectors and create enormous damage to your engine's innards. Follow these seven life-saving steps to stave off the triple threat of water, bacteria, and dirt:
  • Treat your fuel tank with a diesel soluble biocide (there are 2 types, water and diesel soluble - use the superior diesel soluble biocide). 
  • Install dual separator-type primary filters between the fuel tank and engine.  
  • Filter fuel at the pump with a fine mesh funnel (available from marine stores).  
  • Keep your tank filled to 95% when you leave the boat (allow 5% for expansion).  
  • Check the fuel deck fill cap and gasket. That's two things - cap and gasket. A tight cap with a cracked gasket will allow rain water to penetrate into the tank. Keep the cap tight and replace the gasket often.  
  • Change out primary and secondary fuel filters once a year.  
  • Before you start the engine, trace the lines form tank to filters to engine. Look for leaks, weak hose clamps, cracked hoses, and bright, colorless sheen (this indicates a fuel leak). Fix any of these problems before you start the engine!

Keep Engine Blood Clean and Filtered!
What one component gives you the triple advantage of a lubricant, coolant, and dirt-trapper? Nothing helps your engine operate more smoothly than good oil or proper viscosity (thickness) and filtered.

Look in your user manual and note the interval to change engine oil and filter. What do you see? Slice the interval in half. If it says change the oil and filter every six months, put it on your schedule for every 3 months. Become fanatical about checking your oil.

Do not attempt to start any engine before you check the oil level. Check it again after you anchor or tie up. Oil should appear black on the stick. Any brownish or milky threads that show indicate water in the oil. If you see this, locate the source of water penetration and repair the problem before you attempt to start the engine.

Follow this simple advice to keep your expensive sailboat diesel engine running like a top and roaring like a lion. It will reward you with long life, good power, and reliable service--wherever in the world you choose to cruise!


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