Troubleshooting at Sea 101: Diagnosing and Fixing Engine Problems
Have you ever broken down at sea? There’s nothing worse than the realization that something is wrong with your boat. Especially when everything was functioning fine! Unfortunately, this scenario is not that uncommon. Luckily, majority of the times it’s a problem you can fix onboard with the right know-how and a good set of tools. Even though you can’t fix every problem at sea, you can increase your chances of getting out of a pickle by knowing what to look for. With diesel engines, it is important to know that the engine mainly needs two elements. It needs both air and clean fuel in order to run. So if you are missing one in the equation, you’re going to have problems.
There are steps you can take with your diesel engine to help you get back up and running. While there are no guarantees these steps will work each time due to the multitude of variables that can occur. However, knowing the common marine engine problems to look for can help get you running again. ENGINE IS OVERHEATING Back off from the throttle if the engine-temperature gauge or alarm goes off. Before you shut off the engine, take a look at the exhaust and take note of what you see. If there isn’t a steady strean of water coming out, the problem could be a clogged sea strainer or a non-functioning raw-water pump. Shut off the engine. Check the easy thing first, the sea strainer. While you are doing this, ensure that the seacock is open all the way. If there is no water in the strainer this could be from something blocking the through-hull outside the boat. If the strainer is full of clean water, it could be the raw-water pump. A loose or parted belt could be the reason why the strainer is full of clean water, so check that first. If the belt is tight, it could indicate a fried impeller on the pump. This can happen if the engine was started when the seacock was shut. Replace if you have a spare impeller on board. Once the engine is cool to the touch, check your coolant level. …show more content…
Do NOT do this when the engine is hot, otherwise you could get burned. The coolant level should be within a couple inches of the filler point.
If low coolant is the problem, fill it back up to the appropriate level. If you do not have any coolant, top off with fresh water. However, once you get home drain and refill the system with coolant. Also, the coolant had to go somewhere, so check the hoses for any punctures or kinks that are preventing flow.
If your engine thermostat is high and you are experiencing a drop in engine RPM’s, check your prop shaft. Traps can get tangled and wrapped around the prop, creating excess friction.
A bad thermostat can restrict the flow of coolant even once the engine is warm. If you have a spare on board, replace it with the new one. Otherwise, the engine will run without the thermostat so remove it if it’s the culprit. Just make sure you put in a new thermostat as soon as you get home.
If your problem is due to a malfunctioning sensor, a bad head gasket, or has something to do with the heat exchanger and you are a novice mechanic, do not venture any further. Get ahold of a professional.
ENGINE FAILS TO START First things first, check the ignition and power switches. Trying to start the engine with the ignition switch or breaker in the wrong spot happens to the best of us! Check the charge on your battery, or batteries if you have multiple batteries on board. Use your voltmeter, or if you don’t have one, use a multimeter directly on the battery. If there is a charge, check for loose electrical connections. Due to engine vibration its not unheard of for battery and starter terminals to loosen. Make sure your battery terminals are clean, not corroded. Check for any blown fuses or breakers. Check with your multimeter that there is a strong current to the starter. If there is current, the problem could be a bad starter motor or a bad solenoid. Check your oil level. Refill
Have you ever broken down at sea? There’s nothing worse than the realization that something is wrong with your boat. Especially when everything was functioning fine! Unfortunately, this scenario is not that uncommon. Luckily, majority of the times it’s a problem you can fix onboard with the right know-how and a good set of tools. Even though you can’t fix every problem at sea, you can increase your chances of getting out of a pickle by knowing what to look for. With diesel engines, it is important to know that the engine mainly needs two elements. It needs both air and clean fuel in order to run. So if you are missing one in the equation, you’re going to have problems.
There are steps you can take with your diesel engine to help you get back up and running. While there are no guarantees these steps will work each time due to the multitude of variables that can occur. However, knowing the common marine engine problems to look for can help get you running again. ENGINE IS OVERHEATING Back off from the throttle if the engine-temperature gauge or alarm goes off. Before you shut off the engine, take a look at the exhaust and take note of what you see. If there isn’t a steady strean of water coming out, the problem could be a clogged sea strainer or a non-functioning raw-water pump. Shut off the engine. Check the easy thing first, the sea strainer. While you are doing this, ensure that the seacock is open all the way. If there is no water in the strainer this could be from something blocking the through-hull outside the boat. If the strainer is full of clean water, it could be the raw-water pump. A loose or parted belt could be the reason why the strainer is full of clean water, so check that first. If the belt is tight, it could indicate a fried impeller on the pump. This can happen if the engine was started when the seacock was shut. Replace if you have a spare impeller on board. Once the engine is cool to the touch, check your coolant level. …show more content…
Do NOT do this when the engine is hot, otherwise you could get burned. The coolant level should be within a couple inches of the filler point.
If low coolant is the problem, fill it back up to the appropriate level. If you do not have any coolant, top off with fresh water. However, once you get home drain and refill the system with coolant. Also, the coolant had to go somewhere, so check the hoses for any punctures or kinks that are preventing flow.
If your engine thermostat is high and you are experiencing a drop in engine RPM’s, check your prop shaft. Traps can get tangled and wrapped around the prop, creating excess friction.
A bad thermostat can restrict the flow of coolant even once the engine is warm. If you have a spare on board, replace it with the new one. Otherwise, the engine will run without the thermostat so remove it if it’s the culprit. Just make sure you put in a new thermostat as soon as you get home.
If your problem is due to a malfunctioning sensor, a bad head gasket, or has something to do with the heat exchanger and you are a novice mechanic, do not venture any further. Get ahold of a professional.
ENGINE FAILS TO START First things first, check the ignition and power switches. Trying to start the engine with the ignition switch or breaker in the wrong spot happens to the best of us! Check the charge on your battery, or batteries if you have multiple batteries on board. Use your voltmeter, or if you don’t have one, use a multimeter directly on the battery. If there is a charge, check for loose electrical connections. Due to engine vibration its not unheard of for battery and starter terminals to loosen. Make sure your battery terminals are clean, not corroded. Check for any blown fuses or breakers. Check with your multimeter that there is a strong current to the starter. If there is current, the problem could be a bad starter motor or a bad solenoid. Check your oil level. Refill