Check your work!

[Ironworker]

Carl

I was HST for wahoo. The sea conditions were pretty snotty. I was somewhere between 1650 and 1700 rpms which is roughly 16 to 18 knots which is my preferred trolling speed.

[Yannis]

As coincidental as it may appear, I had a very similar experience last year.
Lots of water in the bilge, that I eventually pinpointed to the dripless shaft log.
It wasn't a melted or blocked hose but rather the two rings were not kept snuggly enough together for some reason, letting water in.

I since learned - because I fixed it on my own with instructions from a specialized technician over the phone - that there are a number of little allen screws inside the log that have to either get tightened or replaced in case they are worn. So, you somehow have to remove and check what is the case. So in my case they were worn, the bottom one's edge was made concave and had lost its grip to the shaft...

BUT, where to find new allen screws in inches? And how to measure their diameter in inches? All allen screws I could source were in metric. And none could fit properly. I finally ordered what seemed to be the closest size screws, two or three different sizes, that were flown-in a few days later... Since then, I marked with an indelible sharpie the screw sizes on the bottom of the bilge for future reference...

[Ironworker]

Yannis, thats a good point. Perhaps some Loctite may be in order.

[Tony Meola]

Rick & Carl

I remember Capt. Pat saying something about running a piece of clear hose so that you can see that the water is flowing. I may be mistaken but I thought he said something about a piece with a float ball so you could see it moving.

[Yannis]

Rick,
I don't want to use locktite in such a confined space where you operate on your belly, with allen keys that may slip inside the screw...

You have to remove the top screw and go below where there is a second identical screw...and then there may also be a third one, like in my case.
Too many screws, too little space...if just only one of the three doesn't come out because of locktite you're cooked.

[Carl]

It does seem crazy the set screws only get to be tightened once then needing to be replaced. But it’s what they call for.

I agree about not using the permanent Red loctite, but would not have reservations using the Blue stuff. A drop of it keeps removal easy but provides enough resistance to being vibrated loose…n we know diesels vibrate hardware loose.

[Yannis]

Your diesel Carl, hahaha!!

[Carl]

Ooch!

I have to say I’m quite pleased with mine. At idle, I’ll admit they sound like diesels with injectors popping off. But no smoke n smooth, bump up beyond idle n they get smoother n quieter. The only time they really rattle is on shut down. That’s pretty harsh. That said, I’ve had hardware I couldn’t loosen up for years come apart. Interesting

Yanmars…violent idle n smoky. Love ‘em but


But may have been the few boats with m I’ve been on. Henriques, Trueworld, Albermarles n Carolina Classic

[Tony Meola]

Ooch!

IYanmars…violent idle n smoky. Love ‘em but
But may have been the few boats with m I’ve been on. Henriques, Trueworld, Albermarles n Carolina Classic

Carl

No offense to Yannis, but those dam Yanmar's will be on the Greenies short list for termination. My friends 28 with Yanmar's chain smokes. After 4 or 5 hours of running his transom is black.

The Cummins, after a season of running has some soot on it, but nothing you can see from 5 feet away.

I always thought Yanmar's were better than that.

[Yannis]

Tony, they are!

Your friend has to perhaps send his injectors to a good shop.
As for the Greenies list...I'm sure the Japs will think of something.

[Ironworker]

Another item in the "check your work" series.

I was rerouting some vent hoses for my 3 fuel tanks. I had the floors up and engine boxes out. I was just about to get the job completed, when I looked over the shaft bolts. One appeared rusty and I noticed some rust staining in the inside the Port box. I thought to myself, self where is that rust coming from? I looked over the engine everything looked fine so I decided to pull the insulation of the turbo and wet exhaust elbow. It looked like something growing from a cave on the underside of the wet exhaust elbow.

The weld had cracked on the bottom side and it was apparently leaking.

So a new item on the Annual maintenance list. Remove all turbo and exhaust blankets, inspect for leaks, bad bolts and gaskets!

[Amberjack]

Carl

No offense to Yannis, but those dam Yanmar's will be on the Greenies short list for termination. My friends 28 with Yanmar's chain smokes. After 4 or 5 hours of running his transom is black.

The Cummins, after a season of running has some soot on it, but nothing you can see from 5 feet away.

I always thought Yanmar's were better than that.

As Yannis says, “They are!” My 6LP’s were installed in 2024 and have been excellent engines. Velvet smooth at idle and once dialed in virtually no smoke on the transom. The first few years the transom was embarrassing but after two rounds of prop adjustment (reduction) that went away. My theory is that these are high rpm engines and more sensitive to overloading. They also tended to smoke at idle as I kept them lubricated by over the winter by running at idle for 45 minutes every 2-3 weeks. The mechanic said to run at 1800-2000 after a 10 minute warm up. Problem solved! And now we cruise at at least 3200 instead of loafing around at 2500-2800. They like that better. This has been a good engine choice for us.

[Tony Meola]

Rick

It always good to check the hidden items that we assume are ok. You just never know.

I just uncovered the boat this past weekend. Now I usually don't have my head in the bilge for a week or two after uncovering, other things to get done before I get there. But this weekend I looked and there was antifreeze in the bilge.

Port engine expansion tank was dry. Right now I am baffled, I searched all over that engine and not a stain or wet spot.

Time to pull every hose to find the culprit. If that comes up empty, it must be the freshwater pump.

Always look, you just never know.

[Carl]

Always look, you just never know.

Or don't ever look and live in a happy place!



...although that happy place comes with repercussions. At least for some...aka me.

[Yannis]

When I bought my boat I thought, well, Yanmar suggests to run them at 3000rpm, let me be overprotecting and run them at 2700. I noted the consumption. Then I run them at 2800 and noted the consumption. After 2 or three summers at 2700-2800 I decided to drop my protective attitude and run them at 3000 like Yanmar suggested.
Result? Better consumption than previously recorded!
The 6LP’s turn even higher at 3200 or 3300!

I have some black smoke from my port engine but that engine has one injector that for some reason performs worse than the rest, otherwise no black transom for me.
And like you’re saying, at idle they sound like sewing machines…