Initial Inspection Yanmar Diesel Engine

Installed aboard Indra is a Yanmar inboard diesel engine, model 4JH5E, 4 cylinder, 53.1 hp (39.6kw), serial number E10533, with manufacture date of January 2010. Engine was installed May 2011, while located at Kudat Industrial Estate, Kudat, Malaysia. As of March 2015 at change of ownership, the engine hour meter indicated 757.3 hours. The gearbox/transmission is a Yanmar KM35P serial number 15434 with forward gear ratio of 2.61 and reverse gear ratio of 3.16. As the pictures below reveal, on the surface, visually the engine and gearbox looked in very good shape.

We could not locate any manuals for the engine or gearbox aboard Indra. Fuel and oil filters were discovered aboard with some other minor engine parts/seals. The maintenance log indicated change of the Racor fuel filters - April 2014; change of engine mounted fuel filter - December 2012; had an annotation of a engine hydrolock that had occurred prior in February 2013; and change of oil filters - October 2013. It had no entries documenting change of water pump impeller, gearbox oil, or engine coolant.

The first action we took was to obtain a Yanmar engine installation guidebook (free from the internet); the Yanmar 4JH5E Operators Manual (free from the internet); the Yanmar 4JH5E Service Manual ($15.99); the Yanmar 4JH5E Parts Manual ($80.00); and the Yanmar KM35P Gearbox Parts Manual ($80.00). The service manual had detailed periodic maintenance inspection requirements with replacement of items based on engine operating hours. Due to the engine installation date of May 2011 and 757 engine operating hours we based our initial inspection on the periodic maintenance and inspection requirements of every 1000 hours or every 4 years, which is the most comprehensive requirements the manual listed. Each periodic maintenance inspection requirement was added to an Excel spreadsheet - our master list of Periodic Maintenance Requirements, along with every item needed accomplish it, to aid in tracking future due dates and determining spare provisioning requirements.

Two Parker/Racor 500MA series fuel filter water separators were installed in series starboard of the engine and the instruction manual was obtained from the manufacture website. Recommended maintenance and inspection requirements: Inspect collection bowl daily/prior to engine operation for contamination/water and drain as needed. Replace filters when suspected of contamination; every 500 hours or annually. Per previous owner's log entries these filters were last changed April 2014 and were due replacement. The fuel was drained and both assemblies had 2 micron filters installed. No contamination of fuel or presence of water was observed. Spare replacement filters were aboard and installed per manual instructions after assemblies were cleaned.

Added to the To Do List:

A0109 – Obtain sufficient quantities of spare Parker/Racor 500MA 2 and 10 micron fuel filters.

Engine mounted primary fuel filter recommended maintenance and inspection requirements: Replacement of filter was specified every 250 hours or annually. Per previous owner's log entries the filter was last changed December 2012 and was overdue replacement. The filter was easily removed using a strap wrench. Inspection of filter for contamination was not feasible as it was of sealed canister construction, however the fuel drained out of the canister appeared clean. A spare replacement fuel filter was aboard and installed per manual instructions.

Added to the To Do List:

A0110 – Obtain sufficient quantities of spare Yanmar engine mounted primary fuel filters.

Engine oil maintenance and inspection requirements: Oil level check was recommended daily/prior to engine use. Change of SAE 15W40 oil and replacement of filter was specified every 250 hours or annually. Per previous owner's log entries the oil and filter were last changed October 2013 and were overdue replacement. The engine oil indicated just below full on the dipstick. The cold engine oil was removed from the engine by hand suction pump with difficulty into a clear plastic empty water container. The oil was very dark black and after sitting in the container there were distinct layers of fluid separation - it appeared a thin layer of water was present. No particulate contamination was observed at the very bottom of the container except some oil gelled/sludge pieces. A spare replacement oil filter was aboard and installed per manual instructions.

Added to the To Do List:

A0111 – Obtain sufficient quantities of spare Yanmar engine oil filters.
A0112 - Obtain sufficient quantities of spare SAE 15W40 oil.
A0113 - After initial engine operation (1-2 hours), drain engine oil while hot/warm and inspect for contamination; replace oil and filter.

Gearbox oil maintenance and inspection requirements: Oil level check was recommended daily/prior to engine use. Change of SAE 30 oil was specified every 250 hours or annually. Per previous owner's log entries a gearbox oil change was not documented. The gearbox oil indicated full on the dipstick. Due to access problems, could not get a wrench or socket on the gearbox port side oil drain bolt. The cold gearbox oil was removed by hand suction pump with difficulty into a clear plastic empty water container. The oil was a tannish brown color and after sitting in the container there were distinct layers of fluid separation - it had a layer of water clearly present. Minor particulate contamination was observed at the very bottom of the container.

Added to the To Do List:

A0114 - Obtain sufficient quantities of spare SAE 30 gearbox oil.
A0115 - After initial engine operation (1-2 hours) with gearbox use, drain gearbox oil while hot/warm from gearbox drain bolt location and inspect for contamination; replace oil.
B0116 - To facilitate access to aft side of gearbox for oil change, install and fiberglass two wood stringers on each side of interior hull, above propeller drive shaft, with wood floor panel attached to both stringers.

Engine coolant maintenance and inspection requirements: Check of coolant reservoir level was recommended daily/prior to engine use. Change of long life engine coolant was an annual requirement to be mixed only with deionized soft water. Recommended clean and flush of coolant passageways every 4 years. Per previous owner's log entries a engine coolant change was not documented. The coolant reservoir tank level was discovered about half full on inspection and fluid was of a clear reddish/pinkish color. The hand suction pump hose was attached to the coolant drain port and the engine coolant was drained/pumped to a clear plastic water container. The fluid was greenish/black and had evidence of algae growth in it. After sitting in the container there were distinct layers of fluid separation - it had layers of suspected oil, clear water, green fluid, brown/black fluid, and algae clearly present. Particulate contamination, rust scale, was observed at the bottom of the container.

Added to the To Do List:

A0117 - Obtain a chemical coolant flush/cleaner and thoroughly flush engine coolant passageways.
A0118 - Obtain sufficient quantity of long life engine coolant and deionized soft water.

Water pump impeller maintenance and inspection requirements: Recommended inspection of impeller every 250 hours and replacement at 1000 hours or every four years. Per previous owner's log entries a water pump impeller inspection or change was not documented. The water pump impeller was removed and numerous impeller vanes were discovered missing . Locating the pieces of the missing impeller vanes was now a priority.

Added to the To Do List:

A0119 - Obtain sufficient spares of water pump impeller and cover plate O-rings.

Removed the forward cover on the heat exchanger manifold and discovered excessive scale accumulation. However, of more significance was the upper left area had additional black sealant applied to seal the area in an attempt to compensate for erosion of the aluminum mount face surface for the end cap cover.

Cleaned up the area, installed a new O-ring seal, and reinstalled the end cap cover to determine how large a gap would exist. The gap was large enough to see the O-ring seal and would predict that if operated in this condition a external leak would occur; plus their was a high possibility that the raw seawater for cooling and engine coolant could mix. This could not be reliably repaired using sealant, the heat exchanger would need to be removed, then repaired or replaced.

During removal of the alternator, to facilitate heat exchanger removal, found a disconnected wire and use of substandard automotive electrical wire terminals.

Added to the To Do List:

A0120 - Replace/repair all alternator wire terminals with marine rated heat shrink terminals.

The Balmer Series-6 100 amp alternator also had serious visible surface corrosion. The source of this corrosion was suspected to be seawater leaking from the end cap cover on the heat exchanger directly above the alternator. The white substance in the picture below is suspected to be salt crystals. The alternator was removed and the corrosion extensive enough internally to consider replacement.

Added to the To Do List:

A0121 - Overhaul/repair, if feasible, Balmer Series-6 100 amp alternator.
A0122 - Obtain replacement engine alternator.

Removed the water hoses attached to the heat exchanger manifold and the exhaust water mixing elbow mount nuts - three of the mount studs came out with the mount bolts. After removing two bolt stud nuts and six mount bolts that secure the heat exchanger manifold to the engine, discovered there was not enough side clearance to slide the heat exchanger manifold off the two bolt studs to allow removal. Was able to use vise grips to turn and remove the two bolt studs, and finally removed the heat exchanger manifold. Will replace the two bolt studs with the same type of mount bolts installed in the other mounting holes. The noise absorber pad between the engine block and the heat exchanger manifold separated into pieces and was damaged during removal.

Added to the To Do List:

A0123 - Obtain two additional heat exchanger manifold mount bolts.
Ao124 - Obtain four heat exchanger manifold exhaust mount stud and nuts.
A0125 - Obtain heat exchanger manifold to engine block gasket.
A0126 - Obtain heat exchanger manifold to exhaust water mixing elbow gasket.
A0127 - Obtain heat exchanger manifold to engine block noise absorber pad.

With the heat exchanger manifold removed, took off the aft cover on the heat exchanger manifold and discovered excessive scale accumulation and the missing water pump impeller vane pieces. However once again, of more significance was the lower left surface area had additional black sealant applied to seal the area in an attempt to compensate for erosion of the aluminum mount face surface for the end cap cover.

Cleaned up the area and reinstalled the end cap cover without a seal to determine how large a gap would exist. The gap was large enough to predict that if operated in this condition a large external leak would occur. This could not be reliably repaired using sealant, the heat exchanger would need to be repaired or replaced.

Added to the To Do List:

A0128 - Obtain gaskets and O-ring seals for heat exchanger end cover caps.
A0129 - Repair or replace heat exchanger manifold.
A0130 - Clean scale buildup from heat exchanger core.

Also discovered the heat exchanger manifold to water pump hose fittings were also corroded; right at the ends of the pipe nipples. As a result of this decided to remove the water pump and inspect for similar problems.

The water pump inlet hose that connects to the heat exchanger has a low point loop in its routing. Upon removal of this hose, discovered a very large amount of rust scale deposited at the hose low loop point. The water pump was removed and the inlet hose pipe nipple was also severely corroded, it would also need to be repaired or replaced.

Added to the To Do List:

A0131 - Obtain water pump to engine block gaskets.
A0132 - Repair or replace water pump.

The upper passageway where the water pump mounts to the engine block provided an insight as to the possible condition of the cylinder head and cylinder block passageways, as picture below reveals. Last items in the coolant circuit, the thermostat and lubricating oil cooler, were inspected and minor corrosion was present. The coolant drain cock was removed to increase drainage flow and a garden hose was used to flush the engine through the engine block water pump upper and lower passageways. Significant rust scale was observed as water flushed out the coolant drain cock mount hole but eventually achieved clear water flow from coolant drain port. A chemical coolant flush/cleaner was still needed - reference To Do List item A0117.

Added to the To Do List:

A0133 - Obtain new thermostat, gasket, and O-ring.

Exhaust water mixing elbow maintenance and inspection requirements: Inspect and clean exhaust water mixing elbow every 250 hours or annually. Replace every 500 hours or 2 years. Per previous owner's log entries an inspection or replacement of the exhaust water mixing elbow was not documented. Access to the exhaust water mixing elbow was easier due to removal of the heat exchanger manifold. The exhaust water mixing elbow exhaust manifold inlet had scale accumulation present. The inlet hose clamps from the raw cooling seawater anti syphon loop had significant corrosion present. When attempting to remove the hose clamp, the initial turn of the hose clamp screw resulted in the corroded clamp breaking in half. Additionally, at the same time the opposite end of the hose appeared to have come lose.

Added to the To Do List:

A0134 - Obtain new exhaust water mixing elbow and mount gasket.

Checked the suspected lose hose and found a plastic fitting had broke in half at the raw cooling seawater anti siphon loop T connection that routes water for injection at the propeller shaft stuffing box. Corrosion was present at the clamps.

The 1 inch raw cooling seawater anti siphon hose was a Parker series 7395 E-Z Form SAE J20R2-D1 general service hose. Research on this Parker heavy duty hose revealed its intended use was for the automotive industry and it is not a marine rated hose – Parker does make marine rated hoses. The raw cooling seawater anti siphon loop T connection was made from PVC plastic components not rated or recommended for marine use or for the temperature level the cooling water could possibly reach. A marine rated and approved Forespar 1 inch MF 844 Vented Loop was installed at the top end of the hoses with only single clamps on each end. The vented loop port was attached to a 1/4 inch copper vent line.

Added to the To Do List:

A0135 - Replace all engine seawater coolant anti syphon loop T connection plastic components with marine rated components.
A0136 - Replace all engine seawater coolant anti syphon loop hoses and clamps.

Fuel and water hose maintenance and inspection requirements: Replace every 2 years or 2000 hours. Per previous owner's log entries change of fuel and water hoses was not documented. All water hoses had been removed during the checks for corrosion in the engine coolant system. Each of these hoses along with all the fuel hoses appeared to be of original installation. Outward appearance of the hoses appeared ok except for areas where the clamps had deformed the hose. Almost all clamps had some level of corrosion present.

Added to the To Do List:

A0137 - Obtain replacement engine fuel and water hoses and new clamps.

Until parts were ordered and received, and the heat exchanger manifold and water pump were repaired or replaced, the remaining maintenance and inspection requirements were on hold. The following were recommended to be checked every 4 years or hours indicated and stilled needed to performed.

Check Fuel Injection Timing - 1000 hours.
Check Fuel Injector Spray Pattern - 1000 hours.
Adjust Intake/Exhaust Valve Clearance - 1000 hours.
Check Remote Control Cable Operation - 1000 hours.
Adjust Propeller Shaft Alignment - 1000 hours.
Clean Fuel Injection Nozzles - 1500 hours
Check Fuel Injection Nozzle Pressure and Spray Pattern - 3000 hours.
Check Fuel Injection Pump Adjustment - 3000 hours.