overloading

[RobS]

..at Mainship raftups I checked several new boats, many with Yanmar engines, and I never found one to be close.

When I first started TE shopping I did some reading, etc. and knew the WOT underway was to be 3900+ and always asked the capt to put the pedal to the metal on the sea trials. On the boat I bought she turned just over 3900, with 3 guys and 3/4 fuel so I thought, hey, that's not bad, a little prop tuning and she should be good to go. I had heard that the tachs could be off but this boat HAD a Yanmar tach, so how could an engine manufacturer's tach specifically packaged with the engine not be perfectly accurate. Sea trial with the surveyor's photo-tach showed 3,750. To the contrary, I soon came to find out that the Yanmar factory tach, that came with the B, C and D panels are the most inaccurate of all and non-adjustable ta boot. The 6LP has a 117 tooth flywheel, the tach says right on it 116! Yes that's less than a 1% factor but either it's right or it's wrong, and it ain't right. My Aetna digital matches my photo-tach perfectly. That Yanmar tach is on a shelf in my office..

[Serenity]

Hey guys, I appreciate all of the info and wisdom. I was out of town for a couple of days,and I didn't have time to go out aput the pedal to the metal. If the RPM.s are not reachable, I will be calling B&S to get the propped re-pitched.
On a positive note, the AOG is a great tool to collect thoughts, comments and past experiences. I will keep you posted.

Thanks

[RobS]

If the RPM.s are not reachable, I will be calling B&S to get the propped re-pitched.

Max, If you're turning 3,800 now I would not bother to pull the boat again, wait until the off season.

Just travel alone, run around on an 1/8th of a tank and don't bring any food or beer and enjoy the season!

[Serenity]

Rob, is that your final answer? Are you serious about not pulling the boat? If anyone in the AOG wants a machine to work at 110% it is you. The next thing you will do, would dive with full tanks of N20 instead of an oyygen mix and you can laugh all the way to the bottom.

PS No black smoke at WOT, only a little puff at the line.

[RobS]

Rob, is that your final answer? Are you serious about not pulling the boat? If anyone in the AOG wants a machine to work at 110% it is you. The next thing you will do, would dive with full tanks of N20 instead of an oyygen mix and you can laugh all the way to the bottom.

PS No black smoke at WOT, only a little puff at the line.

A little puff at the line is normal. It's either she's cold or it's the extra load of getting her over the hump btwn hull speed and being on plane. Or a combination of both.

For the type of boating and number of hours (100, 150?) you will clock this season (with even only a percentage of that being under load) I would say yes, that's my final answer. IF you ran that boat under load every day and were to be putting a thousand hours on it this season (non-recreational) it would be a different matter altogether. But if that were the case our 6LP's would certainly not be the engine of choice.

[Serenity]

Rob, great point. How about Cetane levels. Full tank of petrol with stablizer, and all the other condiments we throw in there must have an impact on those numbers, which would affect the performance of the engine. Thoughts

[RobS]

I leave the chemistry of #2 to the people that make it. However, if you feel the need to add something I would focus on lubricity.

[Serenity]

I did that in the Navy. Our diesels were much larger and would consume anything that had oil in it. We ran variable pitch props which I believe they were 18' x 19'. No overloading there.

[RobS]

I brought the prop back and it was repitched.

Max, You bought it has an 18x17, what did they re-pitch it too? Did they take cup out too?

[Serenity]

Rob, I really can't say other than Tom scribed a line on the blade about an 1/2" from the tip. It is stamped on the side of the prop, and I don't think I will see that until the fall. It was not re-cupped. Tom at B&S and yourself are on the same page, in regard to dealing with the 3800 rpm and have it tweaked in the fall.

[RobS]

That does sound like he was addressing the cup. The specs you had previously attached indicated a 0.105 cup which is a heavy cup, what B&S refers to as a #7.

I was figuring that it would not be a one shot deal to get it right so this works out good. Your are good for the season and can tweak it then.

[Serenity]

Filled the beast up yesterday and took on 69 gallons. I paid the same price as last October, $4.26 a gallon, I have been using the new prop since I splashed. My average GPH was 3.93 gph. So far most of my cruising has been at 3050-3100 and that is moving Serenity at 19-19.5 knots. Still WOT is 3770-3800 in all conditions. With wind, against the wind, incoming and outgoing tide.

[RobS]

Sounds good. I pulled up to the fuel dock at Montauk Marine Basin lunchtime Saturday and when I went to look at the pump price the attendant said, "Good timing, just dropped the price last night from $4.29 to $4.14." Montauk is always cheaper than up-island. On Monday heading through Shinnecock Canal I noticed Hampton Watercraft at $4.29, still not too bad. Those are my two "east-end" spots for fueling.

[efishnsea]

If any members get near Sandy Hook the price the other day was $3.76 at Atlantic Highlands Marina

[DougSea]

You're killing me! I drove into NJ yesterday and I was tempted to fill up a bunch of jerry cans. The prices are so much lower there, and they pump it for you!!

I just "topped off" over the weekend for $4.19/gal in Norwalk CT, and that's with the slip-holder discount.