One Vs Two

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FIFTY PERCENT MORE!!!!


Who would want one?
Does it reduce emissions that much?
 
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"In the bigger picture though, it doesn't change my point, that to get a 10% increase in fuel efficiency, one pays 50% more for the engine, and that extra cost will never be recouped."

Add to that turbos only have a service life before rebuild as do inter-coolers.

The turbos are most efficient at good loads , so the turbo boat that cruises at a trawler crawl Looses .

The good news is the exhaust Pea will make it far easier to create legal small mechanical injected engines.

For offshore cruisers , or just folks in FL with hundreds of lightning strikes a day , something to look forward to.
 
Side Note:

“Engine-Only” Maintenance/Repair Costs:

In period of last 30 years I have owned over eighteen (18) gasoline engines (still own six of them). Seven in boats… rest in cars, trucks, SUV.

Except for our 1967 Buick Wildcat muscle-car high performance 360 hp 500 +/- ft. lb. torque engine (which I recently had professionally rebuilt at a cost of about $6K)… the following is my close recollection/guestimate of cost for “engine-only” maintenances/repairs.

I estimate that land-vehicle engines average $400 per year each regarding maintenance (oil changes included) and parts installation/repair – mostly accomplished by reasonably priced professional mechanics I’ve been using for three decades; some items are done by me. Multiply that by 30 years = $12,000 per engine… affordable to say the least in over three decades of well performing engine use. BTW – Not one engine besides the 67 Wildcat ever needed major restoration (and, doing that was a labor of love!). Others of the 18 gas engines never even needed a valve job; I’m very careful in types of lubes used inside all engines. Also – 16 of the 18 engines were/are carbureted.

I estimate that our gasoline boat engines average close to the same maintenance costs per year as do our land-vehicles… however, probably a bit more due to marine costs in general (I perform nearly all actions on boat engines myself; greatly reducing marine mechanic costs).

Long and short of it is that for considerably reasonable costs we get much enjoyment from owning and using gas engines. Especially For Boats – There is great need for care and caution using gasoline engines… but… as long as correct usage parameters and cautionary measures are adhered to everything works very well for the long run.

I have several friends who will pretty much only use diesel engines in their land and boating vehicles. They have mentioned some fairly amazing annual costs. I’d like to learn that TF members estimate they spend annually for diesel engine maintenance/repairs.

Happy Engine-Choice Daze! - Art :speed boat:
 
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Art

No argument with your logic. Except of course that a boat buyer has virtually no choice on the engines installed in the USED vessels we are considering. So we are buying as is with the warts and gold plating imbued in that vessel. Ditto cars with the exception of course that gas vs diesel vs hybrid can be ticked off in the various boxes.

Where the choice comes in with USED boats is that as you buy older vessels you gain the assumed (often wrong) simplicity of a non turboed engine along with deck, window and fuel tank leaks. Or buy newer and get a turboed engine along with fewer vessel build problems.

In the past decade diesel and gas engines in boats are under ever tighter mandates and restrictions due to their shore based design criteria such as on highway, off highway, Tier XX, Euro, NOX, CAFE, CO, particulates designations and mandates. Out of this mess we now have the best and most expensive engines the world has ever seen from the combined criteria of fuel consumption, power per CC, weight per HP, emissions and electronic complexity.

We can rant, speculate, whine, bitch, moan and complain til hell freezes over but there is no going back on the direction engine development has taken. Except for us weekend warriors who spend gobs of money having fun with old cars, pickups and motorcycles adding to asthma and pollution woes. The choices between design age and sophistication are limitless, as is the overall effort to maintain said vessel and purses.
 
Diesel repair and maintenance costs for my two boats are as follows.

Boat-1: 36' sailboat. Engine is a 1987 Westerbeke 46. Repairs on the engine over the 19 years I have had the boat are: rebuild starter ($85), new ring gear the dieing starter chewed ($2,200 - incoudes removing engine, replacing ring gear damper plate, all new rubber on engine, reinstalling engine), rebuild raw water pump ($35), replace exhaust manifold ($850 - included new manifold and new exhaust riser/injection elbow), service injectors ($125), replace manual priming pump after internal diaphragm ruptured ($165), plus annual oil and filter (oil and fuel) changes including zincs ($50/yr). For a total of $4,410 or $232 per year.

Boat-2: 33' displacement cruiser (1936) - Engine is a 2011 Volvo-Penta D2-40. Total maintenance is oil and filter changes at $50/yr. This engine has a monel heat exchanger so there are no on-engine zincs.

Both engines are naturally aspirated, mechanically injected diesels.

I spend a lot more on other required maintenance for the two boats. This year the paint alone I used on the sailboat came to $325. On the powerboat paint and varnish came to $245.
 
TDunn - You dun done it... those are inexpensive costs! Congrats!
 
Me too. My local Chevron dealer is selling diesel at $3.05 and gas (California summer blend) for $3.75! (The refinery is only 20 miles away.)

OUCH! That is expensive fuel!

On the way to work this morning, I saw diesel at 2.79 to 2.99 with 87 gas being around 2.59. NC has expensive fuel taxes too. I don't think I have seen diesel cheaper than gas since ULSD came on the market. Most likely the price was still higher a few years prior to ULSD.

Later,
Dan
 
Turbos don't add to the cost of an engine. Probably reduces it. Remember you are shopping for horsepower, not engine size.

So if you want 200hp at cruise, your choice is either a physically large NA engine or a smaller size turbo engine. And NA engines are not commonly available unless buying used or reman.

I would rather get my cruise hp from a smaller turbo engine than a big heavy NA engine. But my boat and most I'm hired to set up are capable of planing, so they are weight sensitive.

Turbos are quite reliable, too. I'm in the business and turbo failures are quite rare. Most that do fail are due to poor exhaust design, and that would damage an NA engine too. Cat 3208's have a unique erosion issue, and 3116/3126 have a unique low mounted turbo. Those are responsible for most of the replacements I've done or been party to.

I can count on one hand the number of turbos I have replaced that failed for random reasons not explained by poor install design. And this is over almost 20yrs of doing this.

If you need only 50 up to around 100hp, then NA is probably the way to go.

Regarding gas engines, the manifolds and risers require replacement periodically and the cost of that can rival a turbo replacement. The turbo statistically is replaced much less often.
 
Checking our speed tests... 1500/1600/1700 RPMs is in our no man's land, can't plane, mostly plowing. 1800 RPMs is the slowest on-plane speed I tried, and to get there I have to go faster (get properly up on plane) and then pull it back down.

For us, then, 1800 RPMs is approx.13.3 kts and it's still a little "plowy."

I don't have fuel flow scan meters, so can only guess at consumption and economy. The fuel consumption curve suggests 8 GPH per engine, so 16 GPH total, and at 13.3 kts that'd be .88 NMPG.

But the boat is more comfortable at:
- 2000 RPMs, 20.8 GPH, 17.50 kts, .84 NMPG, or
- 2200 RPMs, 26.8 GPH, 20.65 kts, .77 NMPG.

And the hull really performs best -- on plane -- at 2400 RPMs, 34.8 GPH, 23.20 kts, .67 NMPG.

No good news there. We usually run at about 7-8 kts, just below hull speed. :)

Unless weather and sea states dictate faster speeds, in which case we try 2000, if that doesn't work, 2200, if that doesn't work 2400... or whatever else it takes to make the ride comfortable.

-Chris


I should have added our fuel calculations are approx. 3.8 GPH and 1.99 NMPG at about 7.1 kts, and approx. 4.8 GPH and 1.71 NMPG at at about 7.7 kts.

Hence our interest in "trawlering" around. :)

-Chris
 
Fuel burn data
Boat-1: 36' full keel sailboat (15,500 lbs). 19 year average is 0.5 gph at 6 knots or12 nautical miles per gallon.

Boat-2: 1936 full displacement 33' raised deck cruiser (9,000lbs). 0.35 gph at 6 knots, 0.65 gph at 7 knots, 1 gph at 7.5 knots and 2.3 gph at 9 knots (wide open throttle) for 17.1, 10.7, 7 and 3.9 mpg at the various speeds. I generally run a bit over 6 knots for about 15 mpg.

The powerboat has a longer waterline and narrower beam than the sailboat.

Note that miles in mpg is nautical miles. Add 15% for statute miles.
 
Fuel burn data
Boat-1: 36' full keel sailboat (15,500 lbs). 19 year average is 0.5 gph at 6 knots or12 nautical miles per gallon.

Boat-2: 1936 full displacement 33' raised deck cruiser (9,000lbs). 0.35 gph at 6 knots, 0.65 gph at 7 knots, 1 gph at 7.5 knots and 2.3 gph at 9 knots (wide open throttle) for 17.1, 10.7, 7 and 3.9 mpg at the various speeds. I generally run a bit over 6 knots for about 15 mpg.

The powerboat has a longer waterline and narrower beam than the sailboat.

Note that miles in mpg is nautical miles. Add 15% for statute miles.

So, per your stats, if I'm figuring correctly: You get approx. 20 statute mpg at approx. 7 statute mph in your pwr cruiser. They sure don't build em (pleasure boats) like they used ta... and back then... they sure didn't build pleasure boat motors like they do in this 21st century. :socool:
 
Art;331195[COLOR=black said:
I’d like to learn that TF members estimate they spend annually for diesel engine maintenance/repairs.[/COLOR]

Two diesels, so per year is 24 quarts of oil, two oil filters, two Racor 500 filter elements. Don't know how much that totals up to be but in the overall scheme of things it's pretty much free.

Repairs is harder to figure because most years nothing breaks.
 
I have several friends who will pretty much only use diesel engines in their land and boating vehicles. They have mentioned some fairly amazing annual costs. I’d like to learn that TF members estimate they spend annually for diesel engine maintenance/repairs.


Two diesels, so per year is 24 quarts of oil, two oil filters, two Racor 500 filter elements. Don't know how much that totals up to be but in the overall scheme of things it's pretty much free.

Repairs is harder to figure because most years nothing breaks.


Ours is similar. Twin diesels, so per year (minimum) is 34 quarts of oil, two oil filters, two spin-on fuel filters, two spin-on coolant filters (have to remove one to change one of the oil filters), up to 6 zinc anodes (usually replace 2 each year).

Occasionally, 2 Racor filter elements.

We replaced an alternator per survey right away when we bought the boat, almost 10 years ago. We've gradually replaced a few raw water hoses due to age.

Other service points are longer; every 300 or 600 hours, etc. We had the aftercoolers off for cleaning once, an that's coming due again net year. We're flushing the raw and fresh water cooling systems, and changing coolant, this year. Had the valves checked once, on schedule; turned out they needed no adjustment.

Most of my costs are parts-related, since I do most of all that above (but not valves). Even aftercooler cleaning isn't all that costly, since I can do the dismounting/remounting.

-Chris
 
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