Diesel Engine Murder

Murder! Whodunit? YOU committed diesel engine murder!

The deed is done and it is murder most foul. Your loyal diesel engine has met an untimely end, but it wasn’t Colonel Mustard in the library with a Yeti paw or even Miss Scarlett in the foyer with a loofah. It was YOU who murdered your diesel! You cut it down in the prime of its life due to lack of maintenance. Let’s gather the world’s greatest detectives and sleuth through the clues at the scene of the crime to uncover the surprisingly simple ways you sent your engine to an early grave.

CLUE NO. 1: “It’s elementary, my dear Watson. You failed to change your oil.”

It doesn’t take a trip to 221B Baker Street to discover that regular oil changes are the single most important thing you can do to increase the life of your engine. Most engine manufacturers recommend oil changes every 100 hours (or annually, at a minimum).

Some manuals may allow for longer intervals, but more frequent oil changes are a better strategy to extend the life of the engine. It is certainly better than stretching out the period between them. This is particularly true for diesel engines, which tend to be harder on oil lubrication properties than gasoline engines (one reason many experts suggest the oil for diesels be changed every 50 hours of use rather than the 100 hours that are more commonly quoted).

CLUE NO. 2: “Read the smoke signals—six, two and even, over and out!”

Detective Dick Tracy doesn’t need a two-way wrist radio to communicate the cause of your engine’s demise—exhaust smoke is your diesel’s way of telling you what’s going on. Noticing the signs early can head off expensive repairs later. A well-maintained engine may smoke when initially cranked or while idling, but typically not while under load.

White smoke during start-up of a cold engine is normal, but it should clear up after the engine warms. If it continues, it’s normally an indication of unburned fuel. But it can also be a number of other issues, from water or air in the fuel to a faulty injector or injection pump. Black smoke upon startup is also common; however, its presence after the engine is at load signiﬁes incomplete combustion. Possible causes include air intake or exhaust restrictions, compression problems and faulty or worn injectors.

Blue smoke means the engine is burning oil, which is also not uncommon at start-up. Continued smoking may mean trouble with valve guides and stems, worn piston rings or even failing turbo- supercharger oil seals.

CLUE NO. 3: “Observe, Number One Son—air ﬁlter
not replaced!”

You don’t have to be as smart as Charlie Chan to see a pattern here regarding routine maintenance. Even simple ones, such as maintaining your air ﬁlter, can make a big difference when it comes to increasing your engine’s service life. A clogged air ﬁlter not only affects fuel economy, but it can also cause your engine’s turbo (if so equipped) to spin faster in attempts to provide it with adequate airﬂow. Severe damage to valves, pistons and the turbo itself can occur if dirt and debris from a severely clogged air ﬁlter are ingested by your engine.

CLUE NO. 4: “Oh sir, just one more thing… you didn’t change your fuel ﬁlters.”

Columbo knows fuel ﬁlters always seem to clog at the worst possible moment, such as running a narrow inlet or when navigating a busy harbor. Causing your engine to shut down is bad enough, but it gets even worse. Clogged fuel ﬁlters can also damage injectors and injection pumps. Diesel fuel injection systems create a lot of heat and rely on unobstructed fuel ﬂ ow to keep things cool. In extreme cases, excess pressure from a clogged ﬁlter can even cause ﬁlter damage, allowing a failed ﬁlter to dump contaminants directly into the injection system.

CLUE NO. 5: “You poisoned your engine, Monsieur!”

While not as exciting as Murder on the Orient Express, follow Hercule Poirot’s advice to use your “little gray cells,” and you’ll soon surmise that many marine diesel problems originate in the fuel tank. Not surprisingly for boats, water intrusion is a major source of diesel fuel woes. That deck fuel ﬁ ll cap with the missing O-ring is a perfect path for water entry into the fuel tank during every wash down or rainstorm. Limited or seasonal use is also an issue when it comes to boat fuel. Despite the plethora of magic potions and elixirs sold to “kill bugs” or stabilize your fuel, diesel stored on board for long periods can still degrade or become contaminated due to microbial or

Despite the plethora of magic potions and elixirs sold to “kill bugs” or stabilize your fuel, diesel stored on board for long periods can still degrade or become contaminated due to microbial or bacterial growth. Dirty fuel can happen to anyone. If it happens to you, act swiftly to correct the issue, and be sure to maintain good fuel management practices to keep it from ever recurring.

Frank Lanier, Southern Boating August 2017

Tides Marine’s Stainless Cleaner

Tides Marine’s Super Stainless cleaner offers simple removal of unsightly rust or staining from stainless steel. The simple brush-on, rinse-off method passivates the surface to prevent further corrosion. The nontoxic, biodegradable gel-based solution is safe for use around other materials on board as well.

See it in action:

MSRP $27.50 (16 oz.), $37.50 (32 oz.); tidesmarine.com.

Spring Cleaning? Don’t Miss the Engine Room!

Spring cleaning your engine room has long-term benefits.

A dirty engine room is like dirty fingernails; it says a lot about your boat’s overall cleanliness. The accumulation of dust, sea spray, oil, and other fluids in the engine room can affect a boat’s value as well as the boat’s seaworthiness. The boat may look great outside, but it is sick inside and may be dying. “A boat that’s a mess down below can be difficult to repair when there is a problem,” explains Issy Perera, owner of Apex Marine in Miami. “That’s why a clean engine room and pre-flight check at the dock is so critical. Keeping a tidy engine room offers three advantages: It preserves the value of your boat, prevents issues before they start and helps you spot bigger problems faster.”

With some vigorous spring cleaning, boat owners can separate engine room clean-up into three areas:

• Mechanical issues associated with the engine

• Electrical issues with batteries and connections

• Auxiliary systems such as seacocks, sea strainers and watermakers

When it’s clean, problems are seen.

Perera puts down clean, oil-absorbent pads in the engine room so that he can see immediately if there are drips or leaks. During his frequent checks of the engine room he scans for dust that may be a sign of a worn or slipping belt, or if there’s smoke or residue from a leaking exhaust hose.

Anything out of place—loose clamps, wires or hoses—is obviously a sign that something is amiss and needs to be checked out. “There’s an awful lot of stuff in play in the engine room,” says Perera, who runs his 51-foot sportfishing boat to The Bahamas with friends and family. “Once you make a habit of getting down there and cleaning every time you go out, you’ll begin to notice things. You become very in tune with your boat and can also perform vital fluid maintenance.”

Making sure oil is at the proper level and changing it regularly benefits your diesel engine in innumerable ways. While a diesel engine may run at low rpms, it’s still working hard whenever it is running, and the engine oil does more than lubricate moving parts and reduce friction. Oil also keeps pistons and cylinders cool, and protects the walls, valves and turbochargers by acting as a sealant to stop corrosion.

Whether or not to change your own engine oil depends on your mechanical skill level. Most new boats have oil-changing pumps that make it easy to get the oil out, but older boats don’t have such conveniences. You’ve got to get down and dirty to find the oil pan and drain the oil. The bottom line is changing the oil can be a big job that’s not worth the hassle. However, it’s a great idea to know how to change filters and add oil when needed.

Eye on electricity

“Some people will start to spray water all over the engine room, and that’s when things can really get screwed up,” warns Perera. “You have to know what you can and cannot spray. That’s why it can be a benefit for some boat owners to have a qualified marine professional do the maintenance on their boat so they can just turn the key and go.”

Many diesel engines use sacrificial anodes known as “pencil zincs” to counter galvanic corrosion. It’s important to check the zincs often and replace them when they are worn out. “If you let those zincs expire you can have major problems,” Perera cautions. “I’ve seen them wear out after three or four months. Now, they don’t use zincs on all brands, so boat owners need to check their book and find out and then know how to change them when needed.”

Many of today’s diesel engines use covered plugs and connectors for the electrical system, but if you do have exposed connections, there are ways to ward off corrosion. Boeshield T-9 is a spray-on product that creates a film over the exposed connection and protects it from the saltwater environment.

Focus on the fluids

Many boat owners don’t give thru-hulls and seacocks much thought regarding maintenance. They might think of thru-hulls, made of bronze or plastic, as finished-off holes in the boat, and seacocks, also available in bronze or plastic, as simply valves that can be opened or closed. However, when there’s a serious failure of a below-the-waterline thru-hull and seacock, the boat can sink or an engine can burn up when deprived of cooling intake water.

Thru-hull fittings and the seacocks attached to them function as gatekeepers, allowing water to pass into and out of the boat. Thru-hulls are both above the waterline for bilge and A/C water discharge, and below the waterline in combination with seacocks for raw-water intakes for engines, generators, A/C systems, washdown pumps, and more.

When doing maintenance, test bronze thru-hulls with a pocketknife by poking into the flange. If you see bright shiny bronze you are okay, but if you uncover pink, flaky material, it’s time to replace it. Likewise, plastic thru-hulls can crack and leak. Thru-hulls can be fouled by barnacles, and you want to check the seacocks to make sure they open and close smoothly and that there are no leaks.

One cool tool

Finally, Perera recommends every cruising boat owner have a wet vacuum that’s always at the ready. Wet vacs allow for the fast removal of accumulated water, which helps prevent bacterial growth as well as keeping the area clean. “We can help customers clean up their engine rooms, but sometimes it’s a do-it-yourself job and that’s where you have to have the wet vac,” Perera says. “You don’t want standing water or fluids in your boat, and again, any fluid is a sign that something is wrong. Fix the problem, eliminate the fluids, and you’re going to be a much happier boat owner.”

— By Doug Thompson, Southern Boating Magazine January 2017

Hey, There! Subscribe to Our Daily Newsletter