Boat Journal

Chronicling a love affair with sailing

Month: February 2009

Nova

When one does business, it helps to learn one’s market. When one does business internationally, there are problems if one doesn’t understand the language or the culture of the foreign country in which one wants to sell a product. There’s just such a story about Chevrolet, who learned that they couldn’t sell a car called Nova within Spanish-speaking countries. Why? Because no va, in Spanish, is doesn’t go. Not exactly the best name for a car, right?

Well, I digress. It’s just I think of that story when I ponder the situation I find myself in.

My boat won’t move. Well, if I had wind, and pushed it out of the slip, it might. But, as it is now, it can’t be propelled.

The engine isn’t working. And it happened all of a sudden. Looking back at this blog, you can see that the last trip I took out was my solo adventure in October. At that time, the engine was working perfectly. But I went out to the boat about mid-January, on one of those rare sorta-warm days, when my children happened to be in town. And it wouldn’t start. It tried to turn over, but never caught.

So I had the mechanic at the marina take a look. He couldn’t get it to start either. The marina owner said he’d have a look. But, after about 3 weeks, he never got the opportunity, so I asked the guy who’d originally inspected the engine to take a look. Well, by misting it with oil, he got to start, but he said it made an awful racket when it did. He said the engine was dead. He said that he could turn the ?? (don’t remember what) and there was no resistance. He said that meant that there was not compression.

I called and talked to him. Told him that didn’t make any sense, since it had run perfectly the last time. So he said he’d take another look. His thoughts:

As we discussed, m opinion of why your engine is not starting is that there is insufficient compression to support diesel combustion. This condition is readily apparent when the engine is “barred’ through several revolutions at the flywheel and there is, virtually, no “push back” of the pistons as they roll through each compression stroke. I realize that the engine was starting without apparent problems before you laid the yacht up for winter. The contributing causes to lack of compression may be that the piston rings have retracted or seized into their lands (grooves) and are not sealing against the cylinder walls. I have seen this condition before when moisture has found its way into the engine and allowed light rust to “stick” the piston rings in place. From lookng at the engine, it’s also clear that a major overheating event occurred in the recent past. This may have also caused the piston rings to lose their temper or “spring” and contributed to this condition.

More than likely, since the engine has been sitting without starting for some months, any oil that served to seal the piston rings to the cylinder walls in the past has drained into the crakcase, again with associated loss of compression.

As we discussed, my prognosis for this engine is not promising. I suggest that you confirm my diagnosis with actual compression testing of each cylinder with a diesel compression gauge. Any diesel mechanic should be abe to do this for you. Removing the glow plugs and putting some oil into the cylinders via the glow plug holes may fee the rings if they are, in fact, mildly seized in their grooves. Oil may also seal the pistons against the cylinders to the point of improving comprssion to a level that will support diesel ignition. If this is the case, you may find that the engine will start with some reliability if done so every few days such that oil remains “captured” along the cylinder walls and piston rings. I had a Perkins like this that ran on for years but if we let it sit for longer than about a week without starting we would have to open the injectors and squire a few drops of oil into the cylinders.

My hope is that the rings in your engine are, simply mildly stuck in their grooves and that oil and rotation will free them. Of course, I could have complete misdiagnosed this situation and I’ll be happy to learn if this is the case when a mechanic can report back with actual compression reading on each cylinder. The should be about 390 PSI per cylinder.

So, I relayed my conversation to the marina owner. His response:

Before you spend any money on the engine let me think about other causes. I have never heard of all rings “STICKING” at the same time and I was hoping it was an air problem. If it started after misting the cylinders it should start with diesel. Some times the engine will allow cooling water to enter the cylinders through an exhaust valve during engine shutdown so removing the injectors and soaking the cylinders may be the best option now.

And, when lamenting my situation to Dan, he talked with his dad, who knows a thing or two about diesel engines, he, too, thought it presumptive to say the engine was dead. His ideas:

It seems very unlikely that all the rings would stick at once. And I’m not sure that would cause this problem. Now, if all the valves were stuck open, that would make more sense as that would cause a complete lack of compression. But that seems unlikely as well.

Later:

Hey, I talked to my dad and he agrees that it is most likely stuck valves. It should be pretty easy to check by pulling the valve cover and turning the engine over to see if they aren’t coming up all the way.

Dan offered to help me pull off the valve cover to take a look and see what was going on. And that would, I’m sure, save me a bit of money. My concern is that I’d have an engine apart that I really didn’t know how to repair, not that I don’t think I could figure it out. But, between school and work, I wouldn’t have time to do it.

So, for now, I’ll let the folks at the marina see if they can figure it out. They said the first thing they’d do is check the injectors. We’ll see what happens.

Worse comes to worse, I’ll get an outboard again and use that until I can get the engine fixed or 🙁 replaced.