MD11C will not start.

[Lapiki]

I have a problem with my MD11C. I turned it on for 2 hours to generate power. I left my boat for the duration, and when I got back, the motor had turned off. I assumed that it had run out of fuel, added 40 liters, and tried to turn it on. The starter does not work, so I have been hand cranking it. I tried this, and the motor refused to turn. I tried to turn the flywheel with my hand, and still it refused to turn. I checked if the propeller could turn in free-gear, and it could.

I thought maybe water had gotten into the piston chambers, so I pulled the injectors out. I tried to turn the flywheel now, and with some work I could get it to turn. There also seemed not to be any water in the piston chambers.

I tried to hand crank it, and it would not start. It was also significantly harder to get started turning. When I got to sufficient speed and compressed the front piston, it simply made a dull sound and would not even ignite for a few rotations. I noted that there did come white smoke out of the air intake.

The experiment a bit, I tried to instead to compressed the back chamber first(the front one is easier to reach). Now the motor started without problem. More smoke than normal came out of the exhaust. I was exalted, and compressed the front chamber too. After approximately 5 seconds, the motor died out.

I was baffled. No idea what to do. I tried to crank the flywheel, but it was stuck again. I could get it to move a little with a big screwdriver and a bit of levering. I pulled the injectors again. I could get the flywheel to turn fairly easily, but now it was too hard for hand cranking. I could not for the life of me get it to move. I looked at the injectors, and I noted that there was a bit more carbon residue on the front one, so I thought that maybe it was plugged. I cleaned it a bit, and wanted to try and start the motor again. The problem was that it was still too hard to turn.

I tried dripping a few drops of motor oil into the hole for the injectors. I turned the flywheel a bit, and let it sit for some hours. Now it seemed much easier to turn, but still I could not hand crank it. It seems that it is just slightly too hard to turn, to get it to work. I noted that the flywheel turn quite easily most of the way, except for a small part of the rotation, where it gets quite harder to turn.

Sorry for then long post, but I wanted the get a much detail as possible. I am stuck trying to fix the motor. What do you think the original problem was? And how do you thing I get the motor to turn?

[model 10]

How about a stuck valve or broken rocker arm in #1? Pull the valve covers and see.

[Lepke]

Was the engine running at high rpm while charging? No load, just the alternator?

Switch the injectors. See if the problem moves. It sounds a little like the engine got hot or a bearing was dry and seized. Was the oil pressure normal when running on the rear cylinder? White smoke can be unburned fuel. Sounds like it runs on the rear cylinder with the compression release activated on the front cylinder, but bringing the front cylinder on line, but not firing, causes the engine to die. What color was the exhaust smoke?
If the oil pressure is ok and as ECOS suggested, the valves aren't stuck or bad rocker, then most likely starting problem is a bad injector or injector pump. Switching the two injectors should move the problem. If the problem moves, bad injector. If it doesn't move bad injector pump or cylinder/valve problem.

[Nineteen]

Originally Posted by Lapiki

I have a problem with my MD11C. I turned it on for 2 hours to generate power. I left my boat for the duration, and when I got back, the motor had turned off. I assumed that it had run out of fuel, added 40 liters, and tried to turn it on. The starter does not work, so I have been hand cranking it. I tried this, and the motor refused to turn. I tried to turn the flywheel with my hand, and still it refused to turn. I checked if the propeller could turn in free-gear, and it could.

I thought maybe water had gotten into the piston chambers, so I pulled the injectors out. I tried to turn the flywheel now, and with some work I could get it to turn. There also seemed not to be any water in the piston chambers.

I tried to hand crank it, and it would not start. It was also significantly harder to get started turning. When I got to sufficient speed and compressed the front piston, it simply made a dull sound and would not even ignite for a few rotations. I noted that there did come white smoke out of the air intake.

The experiment a bit, I tried to instead to compressed the back chamber first(the front one is easier to reach). Now the motor started without problem. More smoke than normal came out of the exhaust. I was exalted, and compressed the front chamber too. After approximately 5 seconds, the motor died out.

I was baffled. No idea what to do. I tried to crank the flywheel, but it was stuck again. I could get it to move a little with a big screwdriver and a bit of levering. I pulled the injectors again. I could get the flywheel to turn fairly easily, but now it was too hard for hand cranking. I could not for the life of me get it to move. I looked at the injectors, and I noted that there was a bit more carbon residue on the front one, so I thought that maybe it was plugged. I cleaned it a bit, and wanted to try and start the motor again. The problem was that it was still too hard to turn.

I tried dripping a few drops of motor oil into the hole for the injectors. I turned the flywheel a bit, and let it sit for some hours. Now it seemed much easier to turn, but still I could not hand crank it. It seems that it is just slightly too hard to turn, to get it to work. I noted that the flywheel turn quite easily most of the way, except for a small part of the rotation, where it gets quite harder to turn.

Sorry for then long post, but I wanted the get a much detail as possible. I am stuck trying to fix the motor. What do you think the original problem was? And how do you thing I get the motor to turn?

Hi
Sounds like it siezed while you were away - possibly from lack of cooling if the oil level is ok. The fact that you can turn it by hand you may get it going again if you can soak the bores with ATF or oil and diesel.

All you can do is check the cooling water and soak the bores. If you free it up and get it to start then you can troubleshoot the cooling system. If not then it will need mechanical attention.

You shouldnt leave an engine running unattended as a rule - it is easy to suck something into the hull fitting and loose cooling. We ingested a jellyfish and fortunately heard the change in exhaust note before any harm.

Hope you can save it.

Cheers
Tom