"Diesel Engine Maintenance" with Bob Fuller of Infield Marine

Recommendations to Sailboat Skippers

• "Tune up" your diesel with a valve clearance adjustment
• Improperly adjusted fan belt tightness can lead to serious problems
• Check heat exchanger zincs every 2 months and replace when 50% remains
• Change engine oil every 125 operating hours or every six months, whichever is first
• Run your engine at the dock in gear at least every month to keep seals and gaskets lubricated

Bob Fuller and his business partner, Capt. Mike Reitz (of SeaTow) have operated Infield Marine since 1986.  Beginning with over-the-road diesel trucks, they have adapted their business to serve the marine community as well, from the smallest 1-cylinder Westerbeke to the largest Caterpillar marine diesels. 

Bob Fuller, Mike Reitz, and marine diesel technician Jason Dickinson provided a highly informative two hour seminar on the construction and operation of diesel engines, with a focus on raw water, fuel, and engine intake/exhaust valve systems.  

Bob reported that many of his customers had never seen the inside of their own engine rooms.  From the questions and comments of the club members, it was apparent that this is not the case for the WYC community.  The members and guests engaged the Infield experts in an indepth discussion of diesel engine design, care & repair.  Here were some of the discussion threads:

Valve Adjustments - the Infield experts discussed the problems that can occur when the intake/exhaust valves clearances are not adjusted properly.  These can include loss of power, white smoky exhaust, and engine damage.  They recommend that this be done every 250 hours, and remarked that many skippers have Never had this engine tune-up.  They compared it to replacing the condenser, rotor, and plugs and setting the timing in a gasoline engine.

Zincs - Some mechanics recommend not using zincs, in that as they are eaten away by the electrolysis, they leave a residue that clogs up the small cooling tubes in the heat exchanger.  The Infield team strongly believes that zincs that are inspected and maintained properly (replaced when 50% gone) are absolutely necessary, and not using them may violate the engine manufacturer's warranty.

Diesel treatments - the Infield team strongly suggested that fuel additives can help prevent algae and bacterial growth which are much a problem both in fuel supplies and in our boat's tanks.  They also recommended keeping the fuel tanks down to near-empty, since they believed that this would give the bacteria less to eat, and when the tanks were refueled, the contaminated fuel would be diluted with fresh fuel.  The club members were of the strong opinion that keeping the tanks full would reduce the air in the tank that could generate water from condensation.  The difference of opinion seemed to revolve around the fact that we sailboaters may take up to 2 years to burn a tank of fuel, rather than a long weekend like some big diesel powerboaters.  (WYC recommendation:  keep your tanks full and treat twice a year with bactericide.)

Oil changes - The Infield experts definitely recommended frequent changes of both the oil and filter, at 125 hour intervals or every six months.   Clean oil is cheap insurance.  It was pointed out that many skippers don't change their oil more frequently because it is so messy.  Some of the members suggested installing permanent oil change pumps in the dipstick or in the drain plug. Others have had success using the suction pump-type of device (shown).  With this unit, you pump it to create an internal suction then use the hose to scavenge the oil through the dipstick.  You can move the suction hose around the pan to get some of the sludge out as well as the oil.

Infield Marine held a drawing for two hours of diesel service work, which was won by Jim Woodward of "Moby Duck" .  After the general session, the Infield team stayed around and answered boaters specific questions.

WYC Recommendation:  All sailors must be able to perform basic and emergency maintenance on their diesel engines.  This requirement should drive your choice of tools and spares.  At a minimum, you should be able to:

• Change fuel filters and purge air from the lines

• Change engine oil and oil filter

• Troubleshoot and solve engine starting problems

• Replace alternator and properly adjust belt tension

• Drain and replace coolant in freshwater side of cooling system

• Inspect heat exchanger for blockages and corrosion

• Replace engine zincs

• Inspect engine mounts and recognize shaft-engine alignment problems

• Clean water intake strainer and replace cooling impeller