Two Lessons Learned

[Tym]

Hi Tugnuts,

During the very last day of cruising on the "Circle T" during our two-month long PNW trip this year, I learned two lessons which I think are worthwhile to share. The Circle T is a Ranger 29, but I would guess that the mechanical aspects here are the same on all of the Tugs with Yanmar engines. I don't know about the Cummings and Volvo engines.

First lesson: We cruised from Bell Harbor to Blake Island to meet some old friends, and stopped at the pump-out dock to clean out the black water tank before proceeding to the final spot for the night. After shutting down, tying up, and pumping out the tank, I turned the key to start the engine, and for the first time ever, the engine would not start. It turned over strongly, but just cranked and would not start. A check of the engine compartment showed nothing obvious. And, yes, there was plenty of fuel in the tank...

Mercifully, I decided to do nothing and let it cool down thinking that perhaps I had some sort of vapor lock. Meanwhile, I started the generator and ran the battery charger so that batteries would not be an issue. I say "mercifully" as during this time I put in a call to Andrew, and he returned the call before I started to crank the engine again. His first words "Do NOT crank the engine !! Do you hear me? Do NOT crank the engine!!!"

Lesson Learned: If the engine cranks but will not start, you are sucking in raw sea water through your impeller which can end up inside your engine and do damage. Don't know exactly how, but it sounds expensive. Andrew instructed me to close the engine's through-hull to prevent this from happening, and then deal with the problem.

He had me shut down the generator so I could hear, and then have my wife June turn the ignition key one click (to the beep) while I was down in the engine compartment listening for the electric fuel pump. It comes on and runs for about 20 seconds each time the key is turned to the first click. It was working, but was quieter than I would have imagined. (I'd suggest you listen to yours now while it's working, so you'll know what it's supposed to sound like if this happens to you.) She then turned the key to the "off" position, and then back to the first click a total of 8 times, each time waiting the 20 seconds until the fuel pump had shut off. After this, she turned the key to "start", the engine instantly started, and I quickly opened the through-hull. Phew!

After getting the engine started, we cancelled our plan to visit our friends at Blake and elected to proceed non-stop to Everett where there is a Yanmar dealer and where we planned to have the boat taken out of the water for it's return trip to San Pedro, CA. I thought I might have a clogged fuel filter, so was prepared to INCREASE the throttle in case of any engine burps along the way. I also had the enroute alternate marinas in mind. But the engine ran perfectly. An altogether different lesson was in store for us next...

Lesson Two: After 2 months of cruising and about 130 engine hours logged, with less than 1/2 mile to go to the guest dock at Everett Marina, I caught a glimpse of a huge log right in front of us! Too late. I turned the wheel hard left, and then watched as my life's story played out in front of my eyes. After what seemed like an eternity, but in actuality was less than a second, WHAM. After it struck the front and went under the boat, I felt a vibration in the steering wheel. Aughs. We made it to the guest dock and checked for leaks and obvious damage, but appeared to be okay -- my mood notwithstanding.

When the boat was taken out of the water the following day, inspection showed a bent prop blade and a broken prop shear pin. So if the shear pin was broken, how did I move from the point of impact to the dock, and the next day the few hundred yards from the dock to the trailer ramp? Another call to Andrew...

Here's the lesson: Andrew tells me that the propeller's tube for the shaft is tapered, being smaller at the rear than it is at the front. This way, if the shear pin fails like ours did, but the engine is turning in the direction for forward thrust, then the propeller will push itself forward on the shaft but be held in place by the small diameter rear end, and that compression will allow enough torque to enable one to proceed forward at a slow pace and limp home. Pretty smart.

I guess if there's a third lesson, it's that the trip isn't over until the last foot is traveled.

June, Lincoln and I sure enjoyed seeing all of you this summer. Thanks for all you are and do.

 

[knotflying]

Good information! So what was wrong with the fuel situation and what was the reason for turning the key to the initial start position? It sounds like something you would do to prime the fuel system?

 

[Nellie Too]

Tym,
Great lessons, thanks for sharing I hope it all worked out in the end.
All the best,
Bob

 

[baz]

Tym:

Woweee, those two events must have been harrowing for you... they sure would have been for me. I'm glad you were able to get to port after encountering that log... and fortunate that the port was in close range after hitting the log.

Floating logs around the Puget Sound area really concern me and 1st Mate knows why I continually stare at the water in front of the boat. Is it a seal, otter, whale or what do I see ahead... 😱 Even large floating algae patches bother me and I carefully steer around them for fear they conceal more ominous things such as a nasty lurking log.

I've always wondered what the best course of action is when I'm suddenly confronted with the boat heading toward a large floating log. Things are very much worse if traveling at speed.

One option might be to move the throttle lever to neutral quickly and then try to steer and glide by the log. I once went over a floating crab pot line and I quickly went into neutral but the line still got hooked up in the rear. I had other Tugnuts nearby and they came to my rescue... but by the time they got to me the darn line floated astern and I was free to move on. Had I left the engine engaged I bet I would have had a more serious issue with the line wrapping around the prop.

Another option might be to quickly engage reverse -- but this may depend on how fast the boat was moving, how close the boat was to the log, how large/long the log was and one's reaction time. I have played with this maneuver on my R-25. I tried moving along at 8 kts and then quickly moved the throttle lever into reverse. The boat stops quite quickly. However, I need to have something in the water that pretends to be an object to be avoided... such as a sealed 1 gal plastic milk bottle. I can retrieve the bottle after making several attempts at missing it as explained above.

I sure would like to know how the sea water pump impeller could end up in the 'engine' as you described... and I'm sure Andrew is absolutely right about this happening -- he IS the expert. I will certainly keep his advice in mind if ever my engine cranks but doesn't fire up. Having the impeller pieces scattered about in the engine must be a repair nightmare of the worst kind -- if this was what Andrew was thinking. Then again, it might be that the raw sea water could somehow get drawn into the engine cylinders via the turbo and as water isn't easily compressed could cause serious damage with the engine cranking. This would explain why he said to close the raw sea water through-hull valve.

Yes, I always listen for the electric fuel pump whine/whistle while waiting for the beep to end. The pump's wine/whistle is very much louder during the beep period after the fuel filters have been replaced as more fuel has to be pumped in for the lines/filters to get primed. Also, during the beep a series of engine checks are being made to ready the engine for firing up, so I'm told. I also learned the other day that the Yanmar engine has glow plugs installed but aren't connected -- they just sit there and do nothing.

I was under the impression the engine employed closed cooling. That is, the engine has coolant circulating around the engine proper and cools the engine and picks up heat -- this is a closed circuit. This heat is extracted via a heat exchanger. The raw sea water is pushed by the sea water pump impeller through the heat exchanger to extract heat from the coolant. The raw sea water then proceeds on and is inserted in the exhaust stream and exits along with the exhaust through the muffler and then pushed overboard through the hull's exhaust port. If I have this wrong then others can chime in. If I do have this right, then if the impeller breaks up it can get into the heat exchanger and maybe other things. This in itself would also be a repair nightmare.

Cooling system diagram...
http://dl.dropbox.com/u/86512138/YanmarCoolingSystem/Screen Shot 2012-09-20 at 9.17.33 PM.png

 

[bbrh842]

Baz,

I think Tym meant, the raw sea water ends up inside your engine, not the impeller.
If the engine does not start, the water pump is pumping sea water while you are cranking the engine, but there is no exhause to push the sea water out.

On the other hand, if you do not open the sea cock after the engine starts, the impeller will soon desentigrate, and the pieces usually end up in the heat exchanger.

 

[baz]

I was thinking that after re-reading his post and your explanation helps me understand the situation more clearly. Thanks. 🙂

 

[knotflying]

Yes, I think if the sea water cannot go out the exhaust it could build up and can enter through the exhaust valves. This is only my assumption perhaps Andrew can shed some light on that.

 

[Jim Callard]

Tym, Many thanks for the update and glad it all worked out. Interesting that When Cory pulled the boat, I did not see anything indicating a bent prop. Send a pic when you get a chance. I am also reminded of the many things I have forgotten when reading the Manuel's. As we discussed and for other Tug owners, in the Yanmar operation manual on page 34, there is a somewhat obscure notice under "start the engine" that discusses the possibility of sea water entering the cylinders and damaging the engine if the engine is cranked excessive. Who would of thought...... Thanks Tym

 

[baz]

snip...As we discussed and for other Tug owners, in the Yanmar operation manual on page 34, there is a somewhat obscure notice under "start the engine" that discusses the possibility of sea water entering the cylinders and damaging the engine if the engine is cranked excessive. Who would of thought...... Thanks Tym

Got it... Page 34... thanks.

 

[C Dawg]

Thanks for all the information Tym. Did you ever find out why the engine did not start in the first place? Doug.