yanmar fuel consumption/efficiency - 315 6LP

[Serenity]

After putting on 96.4 hours, 362.70 gallons of fuel at an average cost of $4.36 per gallon I averaged 3.76 gph with a 315 Yanmar and the "miracle" prop. Average speed was 20-21 knots at 31-3200 rpms.

[Cape Codder]

OK.....I'll bite.
What is a "miracle prop".........and where do I get one?

[DougSea]

After putting on 96.4 hours, 362.70 gallons of fuel at an average cost of $4.36 per gallon I averaged 3.76 gph with a 315 Yanmar and the "miracle" prop. Average speed was 20-21 knots at 31-3200 rpms.

All of these numbers made sense to me until the speed. Finding it hard to believe you're burning 3.76gph at 20kn. I'm thinking that 20kn is your typical cruise speed (and a good one at that), but your seasonal average speed was likely much lower.

[elad]

I too would like to to know what the miracle prop is. One needs to be careful not to over tax the engine. There sre plenty of prop shops in Stuart FL but none that I know of that will guarantee that kibd of performance.

[Serenity]

In regard to my speed and fuel consumption, check out prior posts on "Overloading", particularity my post dated May 31, 2013. The prop is an Acme propeller, running off of a 1.56 reduction Hurst transmission. This tranny was the original transmission from a Penninsula 300. My top end is 3790. As for witnesses, you may contact Rob of Toy-Riffic and Matt of Dog House. I took these two fine members out for a short hop a while back to confirm my numbers. As for the fuel consumption, it is only an average for the season. I don't have a flow monitor, so it is not possible to measure running fuel consumption. It would be great to run from point A gas dock to B gas dock for 3 hours and determine fuel consumption, but not on the South Shore

[RobS]

Doug: The OP started this thread regarding the 6CX but it took a turn to the 6LP. Can you split this please, thanks!

Max's Serenity is an odd-duck. His combination of the 6LP and lower reduction tranny is simply not what the rest of us are running so we cannot compare our setups to his. She runs like a champ, no doubt there, but he has to slow down when crossing other boat wakes, I don't

I am in contact with the same prop shop (Acme Propeller Dealer) Max deals with but they advise that the current Acme propeller they offer for the 6LP with 2:1 gears 28TE has been tested and the performance was the same or even slightly under what was being achieved with the DynaQuad. Supposedly Acme is engineering something new. Stay tuned.....

[Serenity]

What boat wakes. The Albin is a Blue Water boat. However I do slow down for those 54 Searays that just squat in the water at 20 knots and leave a wake that only a surfer could appreciate

[Serenity]

Just put Serenity away for hibernation. My total fuel consumption for 2014 was 402.1 gallons at an average cost $4.35 per gallon. Average gallons per hour were 5.27. What was interesting, the cost per hour for fuel came out to $23.25. I didn't include repairs, toys, things I didn't need, bait, tackle that I didn't need, food and beverages. Boy, a 3 hour fishing trip cost over a $100.00 and no fish, priceless.

[Tree]

What fuel consumption Max haha? Despite the cost of fuel here we don't really worry about consumption as boating is basically a "volunteer sport". If you can't afford to fill the tank, you don't go. Besides we don't have an end of season really. The boat gets hauled for about three weeks in March for a tidy up and she's put back to sea again. I'd say though that our numbers are similar. We don't really do trolling here as most of our marks are 10 miles upwards out. So it's turn the key and go. I would say we are burning between 6-7 imperial gph.

[deanf]

I recently purchased a 2006 35TE Express flybridge with twin Yammar 6ly-stp. What is my estimated cruising RPM and what speed should I be going at those RPM's and what is top speed and RPM's. Right now I only go about 17 knots at 3200 RPM's.

[whwells]

Dean: There are only about a half dozen of the 35te Flybridge series out there. Even among that small group there are Cummins 370 & VolvoPenta 370 power plants. My guess is that very little study has been done for your limited edition. Sadly, I did not take the time when it was Nibbles.
There is at least one other 35te flybridge in the group with twin yanmar's so maybe he will jump in to help. His is an up galley series & whether that will impact the results I don't know. There are a number of 35te non flybridge series but the additional weight and wind drag for your fine boat will be different.
The boat performs wonderfully as to fuel consumption at a low cruise of 2200 rpm's and reasonable at 3200. Pushing it to 3600 is like throwing away 100.00 bills.
Does not answer your question but the boat is great to 3200-3400. My Certified Yanmar Mech. wanted the boat to be run at full throttle for the last 15 mins back in. Frankly, I never had the guts to go more than 5 minutes for fear something would fly apart.
whwells 'Howard'

[deanf]

thanks Howard. Yeah full throttle is a real waste of money. We got back from Catalina in 1hr 15mins at 27knots and used what appeared to be almost a 1/4+ tank but not really sure. Nothing fell off and it was a smooth fun ride. It seems 3200 rpm's is about 15-17 knots - it just depends. I was hoping for 20-22. That's what I was trying to get clarity on as it seems a little slow. The gas consumption seems non existent at that speed, which is great.

I put in 100 gallons and have made 4 - 20 mile trips on it and used less than a 1/4 tank. I'm trying to get it to empty and fill up soon to get a true reading of everything. We want to make a run out to Cortes Bank, 100 miles out, so I'm trying to get it all dialed in before we go.

It makes sense that with the flybridge the speed is not 20+ at 3200 with the extra weight and wind drag.

Also its a very easy boat to teach my 8 and 11 year old to drive. Thay love being captain with me by their side.

[whwells]

Dean: Sounds too good to be true. Watch out for that guage? Yes, a light throttle really helps. Sure hope my Saber does well and does not wreck my pocket book.
Howard