Roger Long
Senior Member
I’m a fan of the New York Times column “Diagnosis”. The author posts mysterious medical symptoms online and invites anyone, doctors or laypeople, to make the diagnosis. When the column comes out, the first people to send in the correct diagnosis get credited. We’re anchored near highly regarded Ross Marine on the Sono River just south of Charleston, SC where we will be docking tomorrow and a mechanic will come aboard. First person to post here the diagnosis he makes will get an imaginary tee shirt.
Back in Albany, a few weeks ago, I went to start our starboard Perkins 6.354 and it would barely turn over. It acted like an engine with a very weak battery except that there was plenty of power according to the volt meters and the way the other engine lit right off with the two starting batteries connected. When the starter was engaged, the alarm light would dim to near invisibility. I went up to pick the two mechanic’s brains. One said it sounded like hydrolock from a leaking injector. The other said to check all the electrical connections because low voltage due to resistance in one could cause the starter motor to draw excessive current. I went back to the boat, opened up the engine hatch so I could watch the flywheel while starting, and tried again. The engine started right up. Later that day, I discovered that the terminals for one of the starting batteries were loose. The PO just set them on and forgot to tighten them. That was clearly the problem because a number of other electrical gremlins disappeared and the both engines started fine thereafter. These engine, BTW, despite their age start, as quickly as brand new engines – until a couple days ago.
The port engine is still fine. The starboard, contra-rotating engine (which also burns a lot more oil for some reason), wouldn’t start two mornings ago.
I had the two stating batteries (which are also house service on this old boat until I make some changes) hooked together with the “both” switch. It was early so 12V cabin lights were on. The engine barely turned over, like a car with a nearly dead battery. The cabin lights dimmed nearly to invisible and the alarm light on the panel went out. I checked the battery voltage, both were 13 volts. The other engine started normally. I fired up the generator and switched on the battery charger. Engaging the starter produced the same result. I opened up the machinery hatch and watched. The engine made two full revolutions slowly before I decided to stop straining the electrical system. No sign of hesitation at a specific point that might indicated a cylinder with fuel semi-hydro locking it.
Because of my previous experience, I decided to try again about half an hour later. This time the engine started easily and normally.
I decided that, because a waiting period after the problem seemed to work, I would test start the engine first thing in the morning so it could sit for a while during breakfast for another try. This morning, I did that and it started right up normally. We had breakfast and I went to start it to get the anchor up about half an hour later and it was back to acting like the starter engagement was creating a direct short. I watched the voltage meter and it dropped to 4-5 volts while the engine tried to start, turning about 1 RPM. I decided to proceed to Georgetown under one engine and find a mechanic.
Once out in the river, I tried the engine again and it started right up. We therefore proceeded here. After I shut down, I tried restarting the engine and it acts normally. We’ll see what happens in the morning. There is a good chance, of course, that I won’t be able to duplicate the problem for the mechanic. However, we must and will get to the bottom of it. Who wants to take a stab at getting the cyper tee shirt?
Back in Albany, a few weeks ago, I went to start our starboard Perkins 6.354 and it would barely turn over. It acted like an engine with a very weak battery except that there was plenty of power according to the volt meters and the way the other engine lit right off with the two starting batteries connected. When the starter was engaged, the alarm light would dim to near invisibility. I went up to pick the two mechanic’s brains. One said it sounded like hydrolock from a leaking injector. The other said to check all the electrical connections because low voltage due to resistance in one could cause the starter motor to draw excessive current. I went back to the boat, opened up the engine hatch so I could watch the flywheel while starting, and tried again. The engine started right up. Later that day, I discovered that the terminals for one of the starting batteries were loose. The PO just set them on and forgot to tighten them. That was clearly the problem because a number of other electrical gremlins disappeared and the both engines started fine thereafter. These engine, BTW, despite their age start, as quickly as brand new engines – until a couple days ago.
The port engine is still fine. The starboard, contra-rotating engine (which also burns a lot more oil for some reason), wouldn’t start two mornings ago.
I had the two stating batteries (which are also house service on this old boat until I make some changes) hooked together with the “both” switch. It was early so 12V cabin lights were on. The engine barely turned over, like a car with a nearly dead battery. The cabin lights dimmed nearly to invisible and the alarm light on the panel went out. I checked the battery voltage, both were 13 volts. The other engine started normally. I fired up the generator and switched on the battery charger. Engaging the starter produced the same result. I opened up the machinery hatch and watched. The engine made two full revolutions slowly before I decided to stop straining the electrical system. No sign of hesitation at a specific point that might indicated a cylinder with fuel semi-hydro locking it.
Because of my previous experience, I decided to try again about half an hour later. This time the engine started easily and normally.
I decided that, because a waiting period after the problem seemed to work, I would test start the engine first thing in the morning so it could sit for a while during breakfast for another try. This morning, I did that and it started right up normally. We had breakfast and I went to start it to get the anchor up about half an hour later and it was back to acting like the starter engagement was creating a direct short. I watched the voltage meter and it dropped to 4-5 volts while the engine tried to start, turning about 1 RPM. I decided to proceed to Georgetown under one engine and find a mechanic.
Once out in the river, I tried the engine again and it started right up. We therefore proceeded here. After I shut down, I tried restarting the engine and it acts normally. We’ll see what happens in the morning. There is a good chance, of course, that I won’t be able to duplicate the problem for the mechanic. However, we must and will get to the bottom of it. Who wants to take a stab at getting the cyper tee shirt?
