AEROCOOK
Master Chief Petty Officer
- Joined
- Jul 28, 2004
- Messages
- 872
I?m trying to help my nephew find and fix a problem that he?s having with the motor in his boat, it?s a 1986 Rinker with an OMC 4.3.
The problem he has is that there?s water getting into the motor in all 6 cylinders and the oil is also milky too. I asked him to describe the exact conditions that led to the problem and here?s what he said? Hooked up the muffs, turned on the garden hose, started the motor and let it idle for 10 to 15 minutes, shut off motor but left the muffs on with water flowing. Went to restart 20 minutes later and wouldn?t start, discovered water in cylinders and in the oil.
He spoke to a technician at the local marina who said the exhaust manifolds may be cracked so they were removed and tested and were found to be good. He reinstalled the manifolds, changed the oil and blew the water out of the cylinders, restarted the motor, let it run for 10 minutes, shut it off (once again he left the muffs on with water flowing) and the same thing happened all over again, water in the oil and in all cylinders.
I don?t know much about these motors as I?ve always run outboards but I do have a theory that I?m hoping you guys can either dispel or find credible? Is it possible that because the muffs were left on after the motor was shut off that the water somehow backed up into the exhaust and into the cylinders through the exhaust ports? I would think that the water would just flow all the way through the motor and back out but I don?t know for sure. The fact that water is in all 6 cylinders leaves us looking for a source that is common to all cylinders and in my mind that?s the intake manifold or the exhaust.
Any ideas?
The problem he has is that there?s water getting into the motor in all 6 cylinders and the oil is also milky too. I asked him to describe the exact conditions that led to the problem and here?s what he said? Hooked up the muffs, turned on the garden hose, started the motor and let it idle for 10 to 15 minutes, shut off motor but left the muffs on with water flowing. Went to restart 20 minutes later and wouldn?t start, discovered water in cylinders and in the oil.
He spoke to a technician at the local marina who said the exhaust manifolds may be cracked so they were removed and tested and were found to be good. He reinstalled the manifolds, changed the oil and blew the water out of the cylinders, restarted the motor, let it run for 10 minutes, shut it off (once again he left the muffs on with water flowing) and the same thing happened all over again, water in the oil and in all cylinders.
I don?t know much about these motors as I?ve always run outboards but I do have a theory that I?m hoping you guys can either dispel or find credible? Is it possible that because the muffs were left on after the motor was shut off that the water somehow backed up into the exhaust and into the cylinders through the exhaust ports? I would think that the water would just flow all the way through the motor and back out but I don?t know for sure. The fact that water is in all 6 cylinders leaves us looking for a source that is common to all cylinders and in my mind that?s the intake manifold or the exhaust.
Any ideas?
