I have a 96 Mercury 15 hp that I bought last year. The Marina was unsure of the maintenance history, and in spite of the strong stream from the tell tale I decided to replace the impeller this year as a preventative measure(also replaced gear oil and carb gaskets/diaphragms) before taking it out this year.
The water pressure form the tell tale seems to fluctuate in an odd way. The flow never stops, but even at WOT the flow seems to reduce and then increase in a cyclical manner. The engine was fully warmed up in the video below(half mile run across the bay).
This engine does have a thermostat, so I was thinking that since the water was still very cold (42 degrees) that perhaps the thermostat is actually closing, and then opening back up again. I know on some outboard engines the thermostat should open automatically at WOT, but I couldn’t find any documentation that suggested this is the case on this engine. The flow is much stronger at WOT than it is at idle, but it still drops down to a sputtering stream, then back up to full flow at about the same rate as in the video.
Have any of you ever seen anything like this before? Any ideas? … or am I just being a nervous little bitch?
Pressure increases as expected at WOT, but drops and then increases again about every 15 seconds, similar to the video. Just kind of an odd cycling of the water pressure.
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OK, heard back from a friend who checked with a Merc Tech. He says it’s normal and due to the thermostat. I have a larger outboard that has a spring in the thermostat housing that bypasses the thermostat at WOT, and you get a consistent stream from the tell tale. It seems smaller outboards don’t always have that sort of bypass, hence the fluctuating stream.
Yeah, I figured it was the thermostat, I was just expecting the stream to be consistent at higher rpm’s. I use this thing to ferry back and forth to my cottage and an overheating engine this time of year could be a really bad thing if the weather flares up.
Also, don’t forget NY passed a law a couple years back that anyone operating a boat less than 21’ between Nov 1st and May 1st must wear a life jacket at all times. More nanny state nonsense.
This is real? No F’ing way I’m following that. I consider myself to be a decent swimmer and if I’m cruising Silver Lake, you will not find me wearing a life jacket.
Again, for adults it’s only between Nov 1st and May 1st so in 2 more days it will be legal for adults to not wear life jackets, at least until Nov 1st rolls around again. I brought it up because a lot of people have no idea this law was changed and end up getting a ticket if they make an early season run.
Wear Requirements for Personal Flotation DevicesThe following persons must wear a Type I, II, III or V PFD of proper size and serviceable condition:
Children under the age of twelve unless they are in a fully enclosed cabin. The PFD must be the appropriate size for the child.
Anyone operating or riding on a personal watercraft (Jet Ski, Wave Runner, or similar craft)
Anyone being towed behind another vessel such as waterskiers, tubers, para-sailing, etc. You are exempt if you are on a disabled vessel and being towed.
Anyone riding in a pleasure vessel less than twenty-one feet, including rowboats, canoes, and kayaks, between November first and May first.
I just love that it’s only for boats less than 21’. I get the requirement for canoes and the like but I’m no more likely to fall overboard in my 18’ bowrider than the guy in the 21’ bowrider and the water is going to be just as cold for both of us.
Oh, I’m aware of that law. I fairly regularly take out a 14ft aluminum utility boat in small craft warnings, so I wear my safety gear. Especially if I’m by myself. I also make the people in the boat with me wear one until the water is at least in the 60’s. Safety Third and all that.
Last summer a guy who was fishing alone in his bass boat got knocked out of his boat by a wave/wake and drowned right around the corner from my cottage. They think he hit his head when he fell and was knocked out. Someone who was in a boat nearby dove in almost immediately to try an grab him, and couldn’t find him. They found his body 2 days later in 20 feet of water, a couple of hundred feet from where he went in. It doesn’t matter how good a swimmer you are if you get knocked out, or hypothermia sets in.
That is absolutely true. Also, I could see this more for on Lake Erie/Ontario, but not the smaller ones inland. I would have to think that it applies more to canoes/kayaks, but who in their right mind is going out in those kinds of weather conditions?
I have a cottage on an island, the only way to get there or back to the mainland is by boat(or walk across the ice in the winter). Sometimes the weather can turn fairly quickly out there, so you’re either stuck or you go. It’s only a half mile from the mainland to my dock, and my cottage is in the lee of the prevailing winds, and in a protected bay on lake Ontario (Sodus).
There can be close to 4 foot waves on the other side of the island during gales and SCW’s, but they’re only usually around 2 feet on my side. Only big issue is when it’s NW or SSW, but I can get the boat out of the big waves within a couple of hundred yards of the dock in either situation. Like anything else, if you take the proper safety precautions, and know what you’re doing, it’s not all that unsafe. My wife calls it “LT Dan’ing” after that scene in Forrest Gump where they’re riding out the hurricane on the boat.