Engine - MOH or Repower?

[kmacdonald]

There are very few places that can rebuild an engine reliably. Unless you you are near one it's out of the question IMHO. A home garage minor rebuild of a 4 to 8k hour engine will usually buy you 4k hours. 3 to $500. Hone cylinders, new rings, valve job, thermostat, hoses, belts, all gaskets, glow plugs, injector rebuild, water pump, water pump">raw water pump rebuild, and anything else that looks bad. Don't take the head to a machine shop for surfacing. Just clean valves and regrind seats and new valve seals. Machine shops ruin a lot of otherwise good heads.

[MJH]

Originally Posted by Talk Story

It has been quite a few years since I had a cruising boat and I have a contract on a boat whose engine 'purred' at the showing, but has lots of issues.
The engine is a 1989, 77HP Yanmar and during the survey it was determined that it had no engine coolant, almost no transmission fluid, a bad starter and a hot alternator - all at about 4,200 hours. The engine has probably been this way for a couple of years and it has been started and run for 10 minutes a couple of times a month during that time. Not enough to overheat, but not good for the engine.

When I first looked at the boat, I was hoping to put some money ($2-$3K) into the engine to get it to 6,200 hours, but something tells me that if the current owner let all of those sytems sit like that, there is more to be done. Even without the survey in hand I can tell it needs a new starter, new alternator, trannsmission rebuild, a new heat exchanger, etc.

Rebuild? Repower? Wait to find a boat that someone else repowered?

A rebuilt engine is only as good as the shop/man doing the job.

Once the estimate is made and the work begins comes the question...Well sir, since we are already into the engine do you want to replace the whatsit and the gizmo...and the expense begins to increase. When your done, you don't have a new engine, you have a rebuilt engine...there is a difference.

The new-to-me boat I own came with new engine...I'm happy with it.

Good Luck.

~ ~ _/) ~ ~ MJH

[Bawlmer]

You did say the engine purred when it was running. Low oil but did you not say you got an oil pressure alarm (assuming its working). I would rebuild/replace the alternator and starter, flush the cooling system, top off all fluids and take it for a spin. It is a diesel after all.