Just an interesting moment

C

chimoii

New member
I was coming back from a couple of days cruising yesterday and after weaving round the ferries in Swartz Bay I headed through Page Passage. For those who are not too familiar it's an interesting little pass with unforgiving rocks on either side. The tide rips through at a good clip when running and i could see the effect. With 3600 on the tachs I was showing 14mph through the water and between 8 and 9 mph SOG. The water was doing that interesting "boiling" and whirlpool trick and throwing the boat around a bit. I was keeping an eye on the rocks and then the high temperature alarm on the port motor went off. Boy, is that LOUD! I killed the motor and took the starboard one up to 5500. I guess I had some momentum because the speed only dropped to about 9 or 10 through the water and I was able to clear the passage under good control. Once through I stopped the starboard motor and lifted both so the kelp could drop off the port water intake. Thinking back I know I was ready to restart the port motor and risk an overheat if one motor hadn't done the trick but here's a couple of questions.

Has anyone run a motor with the alarm sounding in an emergency and if so, how long have you got before it seizes or ?

I would have reduced drag by raising the port motor but was too busy controlling the boat in the current. Any experience as to how high the steering linkage will let you go if you do need to run on one motor for a while?

Thanks
 
There aren't good standards for how long your motor will run after the overheat alarm goes off. I believe it is thermostatically controlled, and sounds when the temp exceeds a certain threshold, NOT when the cooling system fails to deliver water. So by the time you hear the alarm things are already not right, but still at the high end of operational. From there it depends on a lot: the overall condition of your engine, the quality and quantity of oil in your motor, the presence of any contaminants, what RPM you run the motor while in overheat, etc etc etc. But catastrophic failure CAN happen almost immediately after the alarm sounds. You did the right thing.

The drag created by your disabled motor is not going to be too bad, and if you keep your disabled motor in neutral the prop will spin freely, and this can sometimes clear an obstruction on its own. Usually not. The disabled motor if trimmed down will give you a rudder and help you control your boat, but if trimmed up will put too much wright on the steering system to steer with the speed and control it sounds like you needed to make that pass. Sometimes I'll trim a disabled motor up slightly, perhaps to its highest running position, but not all the way out of the water.

For what it's worth, it sounds like you did exactly what you should have done. I think more than one operator would have been tempted to turn the boat around and head out with the current, which would have probably been a mistake as you would have far less control running with the current under one engine.
 
My Honda motor will continue to run a up to 2K rpm when in an overheat condition (until the engine seizes). It is possible that at that speed or lower, the engine temp might stabilize at a high but not catastrophic temperature. At the very least you would have some power (for awhile) if you needed it.
 
I wouldn't run too long with a high temp alarm. It's best to shutdown and fix the problem. Often if a small bit of kelp (or a piece of plastic) is blocking the intake, just shutting down is enough to get it to fall off since the suction of the impeller is no longer there. If not, shutting down, raising and lowering the motor can be all be accomplished while still underway and done within about 1 minute of time. Then do a restart and see if the temp warning has gone away.
 
rogerbum":1mzufai8 said:
I wouldn't run too long with a high temp alarm. It's best to shutdown and fix the problem. Often if a small bit of kelp (or a piece of plastic) is blocking the intake, just shutting down is enough to get it to fall off since the suction of the impeller is no longer there. If not, shutting down, raising and lowering the motor can be all be accomplished while still underway and done within about 1 minute of time. Then do a restart and see if the temp warning has gone away.
Click to expand...

Thanks for the thought. You are right of course and that's what I usually do. In the circumstances 30 seconds would have me on the rocks if I shut both down. I'm sure my Yamahas can be run at low rpm for a while but that's not going to get me out of trouble in those conditions. A bit like boating in rapids. Turning around was certainly a recipe for disaster. My question was more to ask if anyone had actually blown a motor in such circumstances.

Excellent thoughts about motor and lubricant condition from Kushtaka. There's probably too many variables for a definitive answer.
 
I wasn't suggesting a complete shutdown. I was suggesting that once you shut down the engine with the heat alarm, you could raise and lower it without doing anything different than what you were doing - e.g. continuing to run on the other engine. I had a similar issue this past summer where one engine was giving me an alarm as I was crossing the Columbia River bar. As it turns out, the problem was a faulty temperature sensor but I didn't know that at the time.
 
For starters there is no way anyone can "Monday night quarterback" a decision made under these circumstances.

I apologize, that I don't know the location of "Page Pass" (and could not find it on the internet)-I am very familiar with "Active pass" between Mayne and Galiano Islands, as the one going to and from Sidney to Vancouver. Once I had to go thru that with an adverse current, of over 5 knots and close to red-lining the diesel engine, to make an appointment one Vancouver Island. It was dicey with ferry traffic. I was making 2 knots across the bottom (GPS), and about 8 1/2 knots thru the water on the log. If had to shut down or slow down the engine I would have tried to turn and go with the current--even with the single screw Cal 46.

Often times the whirl pools can be used to your advantage turn the boat--and all you need is water flow across the prop to steer the C Dory (although not as precisely as you can under high velocity rip currents, when the boat is on a plane.) I did a lot of "running" narrow tidal rapids (including Ford's Terror) in my RIB in the PNW (more maneuverable than the C Dory)--and it was surprising how well I could maneuver with minimal power. Timing was essential when making a turn.

I have had a number of high temp alarms --over 90% were kelp, debris or weed on the intake. As suggested, if possible, I reversed the engine, before shut down, and then pulled the lower unit up if that had not cleared the material on the intake.

No way to second guess, but I would have shut down the engine or at least dropped to an idle--and if not making headway reversed the engine, would have turned if possible.

I would not chance throwing g a rod or scoring a cylinder. I might have even dropped to as slow a speed as possible in a relatively calm stretch, and tried reversing the engine. Both to spin the boat, and to try and clear the debris. The Alarm might not stop immediately even if the debris was clear. There are water pressure gauges available for many outboards--which give you even a better diagnostic clue.

Glad it all turned out OK!
 
An obscure pass for sure.

Page Passage (48˚40'50" 123˚23'50" Separates Johnson It and Fernie I from Kolb It and Kamaree It, off NE end of Saanich Peninsula, N of Sidney). William Page (1839–98), who received a Crown grant for land at N Saanich in 1876, was one of the area’s earliest settlers.

Greg
 
I would imagine the impellor would be the first victim with a water shortage and the heat alarm sounding. I would want to check the impellor on that engine before taking any longer trips.
D.D.
 
Aurelia":3cr6fr0c said:
An obscure pass for sure.

Page Passage (48˚40'50" 123˚23'50" Separates Johnson It and Fernie I from Kolb It and Kamaree It, off NE end of Saanich Peninsula, N of Sidney). William Page (1839–98), who received a Crown grant for land at N Saanich in 1876, was one of the area’s earliest settlers.

Greg
Click to expand...

Thanks Greg

i go through Page regularly and never knew about William. I wonder if his friends called him Bill?

Another fun fact:

Bob mentioned Active Pass between Mayne and Galiano islands. That's MUCH bigger. How big is it you may ask?? Well, I learned from a naturalist on board a BC ferry that the volume of water going through the pass when the tidal current is at max is five times that going over Niagara Falls.
 
I went though Active Pass one time in my 32 foot sedan cruiser. There were some little fishing boats around and suddenly they all took off. Into the pass comes the BC ferry. We pass each other and a huge wake is coming towards me. I pick the angle I want to take, slow to idle, and my wife braces herself next to me. About the third wave came over the bow and solid water whacks the window. No damage. I was yelling "Wow, did you see that?!! My wife said "No, I had my eyes closed." We still talk about that.

Mark
 
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