abcandjrc
Well-known member
- Joined
- Oct 10, 2010
- Messages
- 363
- Fluid Motion Model
- C-24 C SE
- Hull Identification Number
- FMLT2160D707
- Vessel Name
- Little Lady (2007)
I'll second what RProffer said about water in the engine, but only because he said it first. I was about to say the same.
The real danger in getting water in the exhaust port is that it will run past one or more exhaust valves, into the cylinders, in quantities sufficient to cause "hydraulic lock". That is when there is more water in the cylinder than the available space between the piston and the head when the piston is at the top of the compression stroke. The starter then tries to push the piston into the incompressible liquid and the general result is a bent connecting rod. And, as the term says, a "lock". If your engine ran, the problem did not exist.
It is possible you had water in the exhaust system but in insufficient quantity to fill the combustion chamber volume and break things. Providence is sometimes most kind. In that event, running the engine has surely cleared up that condition also.
For this particular incident, the potential danger would be if you had not run the engine, in which case the water could still be lurking in there. If in sufficient quantity, it could then break things. In small quantities, it could cause rust on valves, cylinders and heads. In effect, you got away with it this time, but prudence would dictate that if you fear you have injected water into the exhaust manifold that you not try a start without making further checks. That's where the mechanic would have come in if you are not confident in your mechanical skills to check the engine.
The cautions about connecting the hose directly and pressurizing the system are accurate. Feeding the water via a reservoir (e.g. a bucket) and with the water level in that well below the level of the exhaust elbow is a much safer procedure.
Save the mechanic's fees for diesel fuel (and a nice big bucket).
By the way, never run the prop when on the hard. The water seepage into the stuffing box is what lubricates and cools the packing in the shaft log. Running it dry will generally ruin the packing and can score the shaft. If I were you I would just check the packing gland for maybe 8 or 10 drops a minute the next time you have her in the water and are running at a moderate cruising speed. Check it while still in easy reach of your launch site so if you do have a serious leak you can get back to the trailer fairly soon. It will take a great deal of leakng to scuttle her, and the bilge pump is your friend even if the packing is leaking at a serious rate.
The real danger in getting water in the exhaust port is that it will run past one or more exhaust valves, into the cylinders, in quantities sufficient to cause "hydraulic lock". That is when there is more water in the cylinder than the available space between the piston and the head when the piston is at the top of the compression stroke. The starter then tries to push the piston into the incompressible liquid and the general result is a bent connecting rod. And, as the term says, a "lock". If your engine ran, the problem did not exist.
It is possible you had water in the exhaust system but in insufficient quantity to fill the combustion chamber volume and break things. Providence is sometimes most kind. In that event, running the engine has surely cleared up that condition also.
For this particular incident, the potential danger would be if you had not run the engine, in which case the water could still be lurking in there. If in sufficient quantity, it could then break things. In small quantities, it could cause rust on valves, cylinders and heads. In effect, you got away with it this time, but prudence would dictate that if you fear you have injected water into the exhaust manifold that you not try a start without making further checks. That's where the mechanic would have come in if you are not confident in your mechanical skills to check the engine.
The cautions about connecting the hose directly and pressurizing the system are accurate. Feeding the water via a reservoir (e.g. a bucket) and with the water level in that well below the level of the exhaust elbow is a much safer procedure.
Save the mechanic's fees for diesel fuel (and a nice big bucket).
By the way, never run the prop when on the hard. The water seepage into the stuffing box is what lubricates and cools the packing in the shaft log. Running it dry will generally ruin the packing and can score the shaft. If I were you I would just check the packing gland for maybe 8 or 10 drops a minute the next time you have her in the water and are running at a moderate cruising speed. Check it while still in easy reach of your launch site so if you do have a serious leak you can get back to the trailer fairly soon. It will take a great deal of leakng to scuttle her, and the bilge pump is your friend even if the packing is leaking at a serious rate.
