Fuel Burn for 16v92TA?

[saltshaker]

I would find out what it will cost to paint her before you pull the trigger. Years ago, I looked at Striker that needed paint. Quotes to paint it were almost double that of a glass boat. This boat needed a lot of sanding and fairing due to the condition of the paint, but the numbers were outrageous.

FYI I've always heard the number used by most to major 16v92's was 100K per set. When that was all there was for the big sportfish, most owners would budget that in every 3-4 years or 1200-1500hrs.

 

[ThirdHatt]

I would be very comfortable with a quality aluminum boat in fact more comfortable than a quality glass boat. I like steel and aluminum (and I sware it has nothing to do with the fact that I build them ha ha) Seriously I like metal because it doesn't fool your not depending on chemistry in construction. If a metal boat has a problem it jumps out and bites you glass boats are a lot more sneaky about it. The blistering your talking about has 2 causes stainless or other metals that are not properly isolated and im proper painting procedures. The most common problem on recreational boats is the heavy use of fairing compounds over a poor intial prime coat. The good thing is both are obvious and unless the boats just been painted you should see it.

Brian

I am glad to hear that, but I am concerned about the added mainenance of dealing with blisters. The two Browards I am looking at both have blisters at the cap rails and at any right angle. I understand that these will all be properly repaired during the paint job but they come back. Apparently there is no way to stop them from coming back. The paint job price is right at $100k whether I do it here in FL or bring it back to LA.

At the show there are several late 80's vintage Browards for $2.2-2.6M with paint jobs that are 5-8 yrs old and they ALL have blisters along the cap rail! They are telling me that it is regular maintenance to deal with blisters every year. That is not easy to do with Awlgrip because you will always "see" the repairs but they all use Awlgrip. There is a good deal on a big Burger I found out about yesterday and may go look at it today, but again I am intimidated by this extra maintenance of the aluminum hull.

I went on a 1987 Hatteras factory 77CPMY with the engine room access from a big door in the cockpit which is nice because you don't have to haul oil and parts through the boat. No V-drives, just short shafts so VERY smooth running. 12v71ti's and a good owner/captain combo. I felt comfortable and "at home" in the engine room and crawling around the boat. Unfortunately, it has the light white-washed wood that was so popular in the late 80's and early 90's. I was hoping my next boat would have a 20-21' beam and all the Hatt's are 18'2".

 

[Brian Degulis]

I'm not understanding why you have blisters along the cap rail? Is there a stainless hand rail bolted to it? If that's what's causing the blisters there are a few diffrent ways to correct that forever. I've seen lots of aluminum boats like this where the cause of the problem is obvious but it's never corrected makes no sense to me. Plain and simple an aluminum boat doesn't have to blister but of course the causes have to be addressed.

I built an aluminum hard top and radar mast for my Hat. I used stainless fasterners but I insolated with fiberglass washers and sleeves. Now 2 years down the road there is no blistering and there never will be. Around the same time I made an aluminum bracket to hold my davit hook. I went to install it and relized I had no sleeves or washers but I put it on anyway. In 4 months I had blisters.

Brian

 

[ThirdHatt]

Brian, I am not sure exactly why but 5 out of 7 Browards that I looked at have blisters at the top of the hull where it meets the caprail. Two were the ones I looked at buying that were not in the show needing paint/blister jobs, but the other 5 were all several times more money and on display for sale in the show. They all had bubbles under the paint at the top of the hull. THe Captains said that it was indeed time to repair them, but they eventually come back. Not sure what the deal is but I am not a welder and just don't know anything about metal boats.

 

[Brian Degulis]

I think what you would probably find is that those boats are being re painted like glass boats. They probably grind down to clean metal and then build up from there never addressing what's causing the blistering. It would have to be blasted down to bear metal then an anti corrosive must be applied to the correct mill thickness then the fairing and cosmetic steps can follow. I bet it's the skimping on the anti corrosive that's the root of the problem. The fairing compounds and sand able primers are porous so without an anti corrosive if the finish coat is breached then water can migrate down to the metal causing the corrosion that pushes everything off.

Brian

 

[ThirdHatt]

Okay, I finally got a 16V-92TA engine performace curve faxed to me from Detroit Diesel. There is a "fuel consumption" curve that shows @ 1200rpm fuel consumption is nearly 50 gal/hr per engine (seems very high) up to nearly 80 gal/hr @ 2300rpm, which is probably about right.

Just under that curve, there is a "fuel-propeller load" curve that shows only about 18 gal/hr @ 1200rpm (sounds good to me) and goes up to nearly 80 gal/hr @ 2300rpm where it meets the "fuel consumption" curve.

My question is this: Does this engine in gear turning a prop running 1200rpm burn ~18gal/hr or ~50 gal/hr?

 

[Paul45c]

Byron, I'd really think twice about anything Broward -- have you heard the old saying "don't be a coward, buy a Broward."?? Here in the land of the big motoryachts, a lot of people knock them. They're definitely the price boats of the bigger boys. Folklore reputation aside, I also have two friends who have had direct experience captaining them, and they had nothing good to say. One was fairly recently bringing a 95' down from somewhere in the mid-south and he hated the trip...it's really on the big side for many parts of the ICW to feel comfortable in, and yet it had a rough time handling even 5-7' seas with any kind of grace. The boat actually shuddered in those seas, he told me. My boat broker has been on many sea trials for them, and he seconds their poor seakeeping abilities. He was even on one where the hull had parted from one of the stringers.

FWIW, I'd seriously consider the Hatt MYs you cite, blond wood or no. I've just done a lot of veneer work in my 55c. I replaced the old rotted out slider window frames with fixed frameless/seamless. Well and good, but someone had glued mirror to the inside of all the panelling over the "chair rail" height. They glued it so well that it ruined the panelling when I was able to get the mirrors off. A good marine carpenter has bonded 1/4" thick new afromosia panels to the old and it looks stunning. It wasn't that bad a job.

 

[ThirdHatt]

Byron, I'd really think twice about anything Broward -- have you heard the old saying "don't be a coward, buy a Broward."?? Here in the land of the big motoryachts, a lot of people knock them. They're definitely the price boats of the bigger boys. Folklore reputation aside, I also have two friends who have had direct experience captaining them, and they had nothing good to say. One was fairly recently bringing a 95' down from somewhere in the mid-south and he hated the trip...it's really on the big side for many parts of the ICW to feel comfortable in, and yet it had a rough time handling even 5-7' seas with any kind of grace. The boat actually shuddered in those seas, he told me. My boat broker has been on many sea trials for them, and he seconds their poor seakeeping abilities. He was even on one where the hull had parted from one of the stringers.
QUOTE]

WOW! Paul, I can't thank you enough for the advice and real-world experience. I actually had not heard these things you mention before. From what I can gather Browards and Burgers are like Ford and Chevy with respect to build quality, everyone has their personal preference but they are actually fairly similar in overall quality. I know a very experienced surveyor that was personal friends with Frank Denison and he explained to me that Browards and Burgers were in fact quite similar but Broward used three different thicknesses of aluminum in their construction where Burger used two. He said that old man Burger always charged more because he wanted to, but it did not mean that Burger's were any better than a comparable Broward. He also told me that these boats are coastal cruisers and in that capacity they perform well. Those who try to make ocean passages do not belong in these boats.

I would love to stay in a Hatteras but an 18' beam is simply not enough when you're talking 70-85' in length. Also, Hatteras tapers the hulls down so much in the rear that even an 18' beam means a only a 14' wide cockpit. I may just have to wait until some of the semi-custom boats built in the last 10 years come down. Many have a 21-23' beam on a hull from 72-85' in length, now THAT is a stable platform!

Paul, I'd love to chat with you more about the Browards, etc but I can't find your number. I'll send you a PM.

 

[doc g]

Bryan , you read the actual fuel use from the propellor load curve so, 18 gals/hr at 1200 rpm is what it should be as long as the boat is propped to turn out 2300 @WOT....................................................Pat

 

[Brian Degulis]

Yes there are 2 curves one shows what HP the engine is capable of producing at any given RPM that's the engine curve. It will have a coresponding fuel consumtion curve showing what the engine will consume if it's fully loaded at any particular RPM.

The other line is the prop curve it to will have a coresponding fuel consumtion curve. The prop curve shows the fuel comsumtion and HP produced based on the load a fixed pitch prop will require. That's the one your interested in that shows the consumtion you can expect with the OEM configuration at any particular RPM.

If you look at the 2 curves it's easy to see why fuel consumtion is so much lower in the lower RPM range. Your only using a fraction of the HP available as you increase RPM you use a higher and higher percentage of available HP up to WOT @ 100%

Brian

 

[ThirdHatt]

Pat and Brian, thank you both for confirming my suspicions. I mis-read the graph before. It is actually 13gph at 1200rpm, not 18. 13gph per engine to run at displacement speed is very reasonable considering the size/hp of those engines. Hmmm.

 

[Brian Degulis]

Check the HP on the prop curve @ 1200 RPM the fuel consumption rate would indicate around 210 HP being produced per engine. If that's about right it sounds like a lot for displacment speed. I know it's a big boat but it's probably not all that heavy and 420HP sounds high. I'm guessing you could do better than 26GPH at displacment speed.

One of the nice things about a long boat is that it doesn't take a whole lot of HP to run at displacement and because of the lengh the displacment speed is high. So you GPM OR MPG can be better than a smaller boat.

Brian

 

[ThirdHatt]

Brian, the "power-propeller load" curve shows something between 175 and 190hp at 1200rpm. I cannot read it more accurately than that due to the thickness of the line. I tried to scan and import it earlier when I got it so that I could post it here, but no luck.

I am intrigued that I could run these motors like I run my 8V71ti's, 1200rpm all day then just spin them up for a short time to clean them out. I hate the idea of twice as many holes to deal with when rebuild time comes around though.

BTW, the weight is listed around 155k lbs, but if it carries 9k gals of fuel and 1k gals of water, that is a HUGE swing in displacement depending on load. Fill 'er up while fuel is cheap and cruise for several years @ 1200rpm?