Water up the.....

[GufShoz]

Has anyone had the experience of water being forced into their engine through the exhaust? I have a Hunter 29.5 (new to me) with a Yanmar 2 GM that I was able to draw salt water out of the injector hole in the top of the rear cylinder. The boat went through a rough time during TS Lee on Labor Day at my marina. Three ft waves were rolling in and I was tied stern-to a seawall, so the waves were rebounding against my stern. The boat seemed to come through okay, but when I tried to start it a few weeks later the engine had seized. That's when I tried to remove the salt water and put in Marvel Mystery Oil for several days. Alas, to no avail. Should the anti siphon valve stopped this? My insurance company covers storm related damage, and they're questioning whether the storm actually forced the water into the engine.
I would appreciate anyone's experience or ideas.

[kd3pc]

depending on the waves, the wind and how the exhaust is run from the engine to the thru-hull....it happens.

More than a few hours after the water sits, it is too late for pickling the engine or doing the marvel oil...you may get lucky, but I would not count on it

I doubt the anti-siphon could have stopped the water from being slapped in to the thruhull.

Likely storm damage, but you may have to explain it to the adjuster, especially if the insurance is Progressive or one of the "car companies" or home owner policies

[knuterikt]

Originally Posted by GufShoz

Has anyone had the experience of water being forced into their engine through the exhaust? I have a Hunter 29.5 (new to me) with a Yanmar 2 GM that I was able to draw salt water out of the injector hole in the top of the rear cylinder. The boat went through a rough time during TS Lee on Labor Day at my marina. Three ft waves were rolling in and I was tied stern-to a seawall, so the waves were rebounding against my stern. The boat seemed to come through okay, but when I tried to start it a few weeks later the engine had seized. That's when I tried to remove the salt water and put in Marvel Mystery Oil for several days. Alas, to no avail. Should the anti siphon valve stopped this? My insurance company covers storm related damage, and they're questioning whether the storm actually forced the water into the engine.
I would appreciate anyone's experience or ideas.

Never experienced this - but it is a possible scenario.
The anti siphon valve will not prevent this, the anti siphon valve is there to prevent water siphoning from the sea water intake.

There are two ways to prevent water going into the exhaust pipe

• A flap on the outboard end
• Leading the exhaust pipe upwards from the outlet to prevent water "klimbing" into the engibne (kind of water lock)

AFAIK there are three different ways to get sea water into the cylinder

1. Defective or missing anti siphon valve
2. Defect in the the sea water injection bend (causing sea water to flow into the cylinder)
3. Water being "pushed" into the exhaust by the waves (while the engine is stopped)

If you can rule out the two first, its must be the third.

[Capt Len]

Several thoughts on this. If the vessel is bobbing bow to stern, water in the exhaust hose can hydraulic (ram) over the hump and fill the muffler and engine This can happen anchored or sailing in big following seas. Needs a good flopper over the outlet and/or an internal shutoff at the transom. Blade valves from RV sanitary tanks are easy to adapt to the existing hose.I went one further and installed a valve in the aqualift muffler It was a manual ballvalve on a pull cable from the cockpit that opened when the engine off cable was pulled.I've since changed it to a solenoid valve open till oil pressure so it's foolproof.If you place the valve in the bottom of the muffler it all drains into the bilge. If on the side little or no drainage occurs unless the anti siphon fails.I sleep better now

[christyleigh]

Originally Posted by GufShoz

That's when I tried to remove the salt water and put in Marvel Mystery Oil for several days.

How did you try to remove the water? A few years ago I had called in a mechanic to help me with my no start/seized - hydrolocked 4 cylinder Yanmar. While he was discovering water in the turbo intercooler I was discovering the reason for it all. Mud Dauber Wasps had built a nest in the outside vent for the anti-siphon loop rendering it useless. So a couple weeks before on a normal shutdown I sucked water into the top of the cylinders.
The fix was simply to pull all the injectors, crank over the engine, and force the water out of the cylinders .....all over the pilothouse and him until he realized what a mess it was making, stopped and put a board over the holes to keep the splashing under control.
Of course we had checked the oil before and after this procedure and there was NO Milky oil/water mix. So.... injectors back in fired it up. He suggested checking for Milky residue often and that I should probably change the oil anyway - end of story. Saved by good compression rings.