Switching Gears....on to the Engine!

With the deck paint finished (sans non-skid), I am switching gears on boat work.  I've been doing a bunch of different odd jobs such as rebuilding the deck hatches, restoring bronze hardware, and working on getting the drains installed on deck. I also decided it was time to start diving into the engine project.  The engine was removed from the boat early last year and has sat on the ground of the yard untouched this whole time.  I recently moved to a place with a garage, and I wanted to get the engine protected and in a space that I can begin to work on it.

The engine itself is a Yanmar 4JH2E, a 52 hp naturally aspirated marine diesel.  This is Windsong's second engine, and was installed in 1992.  It only had 900 hours on it when I purchased Windsong, and the young engine was one of the selling points for me.  However, the engine had sat in the closed up Windsong in the Florida heat for about a decade, and the destructive humidor environment caused havoc to the engine's parts.  The paint had peeled away in many spots, rust and corrosion were having their way on bolts and a few certain parts, hoses were cracked and loose, the motor mounts were nearly rusted through, the shaft seal was leaky, etc.  However, beyond all that, the engine started up quick and ran smoothly from the beginning.  Despite its looks, it worked wonderfully.

The trouble began on the first time I took Windsong out for a ride by myself.  For the full story, refer back to this post.  Long story short, the engine's water pump impeller wore out during that ride and caused the engine to overheat due to lack of cooling water.  At this point in time, I knew practically nothing about how these engines worked, so I just added some coolant to the tank and drove the boat home while it was overheating.  It was probably a total of 15-20 minutes, and that time of overheated running has caused loads of concerns for me.

We eventually got the impeller replaced and the engine ran wonderfully again.  I put roughly 100 hours on the engine when I took Windsong around Florida, and it ran smoothly the majority of the time.  The only problems that we faced dealt with a very dirty fuel tank, some loose hoses, a poor shaft seal and bad motor mounts.  When it was getting clean fuel, it ran great.

So what do I plan on doing to the engine now?  I had contemplated a full rebuild, but these things typically last 5,000-7,000 hours before a rebuild is needed.  However, given that I have it out of the boat and in a great working environment, I will give it a good restoration and possibly dig deeper than necessary for educational and experience purposes.

The plan right now is to:

-Clean thoroughly -Remove and replace all rusted/corroded bolts and fittings. -Ensure all good bolts can be loosened for future repairs (use anti-seize compound) -Replace Starter Motor (works, but is corroded on outside.  Will refurbish old one as a spare) -Replace Motor Mounts (all 4 were rusty, two actually rusted through and broken) -Replace Air Intake Silencer (Rusted enough to where the brackets will not function) -Replace all water and fuel hoses (including some exhaust hoses) -Replace alternator (use existing as back-up, upgrade amperage output in new) -Clean heat exchanger/exhaust manifold, replace gasket -Replace thermostat and gasket -Replace mixing elbow gasket -Replace belt -All filters, fluids replaced

Related issues: -Thoroughly clean fuel tank -Get shaft inspected -Replace shaft seal -Replace Cutless bearing

Beyond all of that, there are a few things I can optionally do.  This really goes into the question of "if it ain't broke, don't fix it"; or "check it out now while it is easily accessed".  Since I did run the engine hot for a bit, the biggest question mark is the condition of the head and head gasket.  Therefore, I might open up the head to get a look at the condition under there.  This would require a replacement of the head gasket, regardless of condition; and getting the head checked for any warping.  If I open up the head, however, I might as well do some extra work such as cleaning and checking valves, checking injectors, etc.

Right now I am leaning towards opening up the head for educational purposes and piece of mind that everything is OK under there.   I like the idea of dissecting the engine now, and knowing how to do it for the future, versus having to do it in the boat and in a confined and awkward space.    If I have to do it in the future, I will at least have the experience to know how to do it.

If you have any engine experience and think I should do something not listed here, please chyme in.

Check out these galleries for engine goodness.  Some people prefer looking at the photos on Facebook so I included all forms of the galleries:

Engine part 1 - Disasssemby Reference Photos - Website Photo Album Engine part 1 - Disassembly Reference Photos - Facebook Photo Album

Engine part 2 - Restoration - Website Photo Album Engine part 2 - Restoration - Facebook Photo Album

Some choice pics of getting the engine from the boat to my house: