Extended Cruising vs. Outboard Power

[rslifkin]

Originally Posted by valhalla360

But outboards typically come with flushing ports (or you can put muffs on them). Inboards have to use the more expensive parts because most are not designed for easy flushing.

Again, we simply didn't have any issues.

Another thought...I know the big outboards are expensive but so are diesels.

When we bough our 25hp, it was $5k brand new installed. They came out to the slip with a truck with a small lift on the back and lowered into position. 2hr later, we had a complete new drivetrain. A similar size inboard would be running 3-4 times the cost, the boat would need to be hauled and it would likely take a week to get the work done. We could replace the engine every 7-10yrs and after 30yrs, it would still be cheaper.

Small outboards are cost effective, but big ones aren't. A quick search turns up the price for a 400hp Mercury Verado as about $34k. The 425hp Yamaha XTO is about $45k. A gas inboard of similar power is significantly cheaper (even once you add a transmission). The 425hp Mercruiser 8.2 HO comes with closed cooling (the outboards don't) and lists for about $27k. About another $3k for the recommended ZF63A transmission and you're still cheaper.

Going to diesels will cost more than the outboards, but not dramatically more. From what I can find, a 425hp Cummins QSB 6.7 plus transmission shouldn't cost more than $50k.

[valhalla360]

Originally Posted by rslifkin

Small outboards are cost effective, but big ones aren't. A quick search turns up the price for a 400hp Mercury Verado as about $34k. The 425hp Yamaha XTO is about $45k. A gas inboard of similar power is significantly cheaper (even once you add a transmission). The 425hp Mercruiser 8.2 HO comes with closed cooling (the outboards don't) and lists for about $27k. About another $3k for the recommended ZF63A transmission and you're still cheaper.

Going to diesels will cost more than the outboards, but not dramatically more. From what I can find, a 425hp Cummins QSB 6.7 plus transmission shouldn't cost more than $50k.

Keep in mind, the OP provided a link to a boat with a pair of 200hp outboards.

Yeah, if go into the extreme high performance end of the market the prices can get distorted. Of course, it gets tricky installing 4 x 425hp diesels in a cigarette boat or a single on bass boat which is really where these engines are marketed for.

Drop back to a more typical 250hp model and you are looking at around $12-15k and installation shouldn't take more than an afternoon. That includes transmission, prop, propshaft, alignment, etc...

Retrofitting an inboard engine can easily add $5-10k, especially if the motor mounts don't line up and you have to do fiberglass work.

[Whoosh]

"If you are running 3 x 300hp engines, you will be at marinas regularly..."

Very true...but that's not the kind of boat we're discussing. I used Navionics the other day and did a route plan that had me leaving Biscayne Bay via Gun/Cat Cays and NW Channel light to Chub to clear, didn't refuel, hopped over to Nassau (did refuel) and then went out to the Exumas and gunk holed all the way down to Georgetown to settle in for a spell (and again fueled). This is the kind of limited cruising I'm referring to. I assumed the boat in the link above (good rpm vs. fuel burn data is available) and assumed a range of speeds (hull speed to low 20's at 1.5 GPM). With only two refuelings needed, it's pretty clear fuel in this case isn't the limiting factor. But there I am, in Georgetown and with two choices. I can backtrack all the way to Brown's in Nassau just in time to haul for my 100 hr service, or carry on what I'd really like to do by visiting Acklins again and then back southwest to more islands but exceeding the engines' service interval.

While these 100 hr service intervals generate repetitious expense, it's true this isn't a logistical problem while cruising within the U.S.. The puzzle is whether doing the typical wintertime cruising in the islands is feasible without distorting one's travels too much. Sadly, it is also likely that going even a little bit further - say over to Provo in T&C, let alone down to Luperon in the DR - just isn't feasible. Not one lift in that whole area to my knowledge, and tidal ranges aren't all that large either.

Jack

[valhalla360]

Originally Posted by Whoosh

"If you are running 3 x 300hp engines, you will be at marinas regularly..."

Very true...but that's not the kind of boat we're discussing. I used Navionics the other day and did a route plan that had me leaving Biscayne Bay via Gun/Cat Cays and NW Channel light to Chub to clear, didn't refuel, hopped over to Nassau (did refuel) and then went out to the Exumas and gunk holed all the way down to Georgetown to settle in for a spell (and again fueled). This is the kind of limited cruising I'm referring to. I assumed the boat in the link above (good rpm vs. fuel burn data is available) and assumed a range of speeds (hull speed to low 20's at 1.5 GPM). With only two refuelings needed, it's pretty clear fuel in this case isn't the limiting factor. But there I am, in Georgetown and with two choices. I can backtrack all the way to Brown's in Nassau just in time to haul for my 100 hr service, or carry on what I'd really like to do by visiting Acklins again and then back southwest to more islands but exceeding the engines' service interval.

While these 100 hr service intervals generate repetitious expense, it's true this isn't a logistical problem while cruising within the U.S.. The puzzle is whether doing the typical wintertime cruising in the islands is feasible without distorting one's travels too much. Sadly, it is also likely that going even a little bit further - say over to Provo in T&C, let alone down to Luperon in the DR - just isn't feasible. Not one lift in that whole area to my knowledge, and tidal ranges aren't all that large either.

Jack

I think we need to define a speed and fuel consumption a little better...big difference in consumption between hull speed and low 20's. Assuming hull speed is 7, that's around 700-2300miles between oil changes. If you are mostly running at hull speed, you can probably extend a bit as you aren't working the oil as hard (this assumes the engine is getting up to temp fairly regularly).

If you are always running at hull speed or less, consider getting smaller motors as running to light a load isn't good for an engine (not just outboards).

Also, I assume you mean 1.5GPH not 1.5GPM? 1.5GPM~90GPH. What speed is this in reference to?

You might need to check how it would work on the model you are looking at... but if we needed to do an oil change in water, I would raise the motor, slide the dingy under and wrap the leg with a big heavy duty trash bag to catch any drips. This allowed changing both the engine and lower unit in a calm location. I believe you can get a vacuum extractor to pull it out of the dipstick as an alternative, so not much different than doing a diesel.

[Whoosh]

Valhalla, you and I are on similar trains of thought re: service intervals. (BTW I'm assuming I'll have the kit of bits & tools and will be doing the service myself). The puzzle morphs from how to honor the 100 hr service level to 'Can I do the critical parts of the service in the absence of a lift or large tidal range, completing the rest when the location is more suitable?'

I would expect speed (and so fuel consumption) varying depending on the leg, or at least that's how I was route planning the other day. Moving along the lee sides of the Exuma chain is a great time to benefit from planing speeds: almost calm waters inshore and short distances. OTOH crossing the banks from Gun/Cat, I anticipated hull speed as there's always some amount of chop and swell to contend with, not really desirable in this kind of boat unless one gets lucky with the conditions. In any event, there are usually multiple accessible fuel sources in the Bahamas given the range of these boats. Fuel really doesn't appear to be the issue.

1.5 GPM? I said that backwards, didn't I. That was meant as the estimate of 1.5 MPG at planing speeds. E.g. that 895 in the review above shows 4000 rpm gives ~25 MPH = ~21.5 kts with 14.5 GPH or 1.6 MPG (or ~1.5 NMPG) under calm conditions. Not that good in less calm waters, but then that's when one might need to plan the leg at hull speed.

I've noticed the 'suck the oil out of the dipstick' approach for an oil change is shown in some videos as being service techs choice, something that surprised me. Not an option for the gear leg under the circumstances we're discussing. I need to ID how far down the gear leg the impeller is mounted on these Yamaha 200's.

This is proving a fruitful discussion. Thanks to everyone who's pitching in.

Jack

[valhalla360]

As long as you can get into calm waist deep water and the leg comes clear of the water, you should be able to use my garbage bag trick to get the lower unit gear oil. It takes a little planning and maybe an extra set of hands but it's doable.

I saw too when I was checking on these larger outboards and at least Yamaha posted that the dipstick method is the preferred method and the drain plug may actually leave a bit of oil in the sump. I always thought it was the opposite.

[ranger58sb]

Originally Posted by Whoosh

While these 100 hr service intervals generate repetitious expense, it's true this isn't a logistical problem while cruising within the U.S.. The puzzle is whether doing the typical wintertime cruising in the islands is feasible without distorting one's travels too much. Sadly, it is also likely that going even a little bit further - say over to Provo in T&C, let alone down to Luperon in the DR - just isn't feasible. Not one lift in that whole area to my knowledge, and tidal ranges aren't all that large either.

I suspect you could generally plan your route around service intervals. First, the engine doesn't explode at 101 hours. Second, you could do a major "100 hour" service at 82 hours just before leaping offshore, then do the next "100 hour" service at maybe 120 hours after returning to someplace useful.

And a lift is not required all the time, anyway. I've seen service guys at an outboard boat in the water, standing on a platform doing the work...

You might want to do a full comparison of projected costs versus similar boats with gas inboards and diesel inboards... to better inform your decisions. Especially if you factor in the "new vs used" opportunities. There are probably a bazillion choices of gas and diesel inboard boats that offer the same type of living accommodation... and that can partly speak to easier dinghy/tender issues as well.

-Chris

[Whoosh]

Chris, you're surely correct that boat choices are all but infinite. Just up in your area, around the Bay, one can find enough candidates to fit a mission profile and budget to get one's head spinning. Still, for now I'm trying to work through the suitability of this relatively new kind of boat that's arrived in the market, which I guess I would summarize as: planing hull, single level 'cockpit to helm & galley' layout, excellent 360 visibility, engine redundancy, and of relatively new construction, all for around the $250K price point.

Re: your point about techs servicing outboards while afloat, I think you're right that this is less of an issue than I initially realized (which is also the point Valhalla was making). I finally came across a very thorough 100 hr service tutorial for a Yamaha 200 outboard on Youtube last night and it offered two big takeaways for me. First was what service points are considered essential along with how to do them: engine and lower leg oil replacement, and oil filter, onboard fuel filter and primary fuel filter replacements. All those steps are likely done in still water if one doesn't suffer from the 'dropsies' with tools and parts. The second 'ah-ha' was how much more involved changing the lower leg's impeller was than I expected. That's simply not something I would attempt while afloat. (So I guess that means half my puzzle was addressed...but not all of it, if impeller replacement is necessary at 100 hrs).

Jack

[CarlF]

Assuming the boat is designed for an outboard (weight distribution, transom), a modern 4 cycle outboard up to around 200hp has lots of advantages over a diesel inboard. It's too early to know about the longevity of the big 300hp+ outboards so the following is about the mid size 200hp ones.

Reliability - up to about 200hp these engines are basically small Japanese car engines mounted on the side. In a car these will run 200,000 miles with few if any repairs.

Repair cost - Changing oil and filter on an outboard is typically easier than on many inboard - no pumping required - just open the drain. The only hard thing - the impeller - requires getting the engine out the water but this can be done when the boat is hauled every few years anti-fouling paint. The cooling systems of these outboards are MUCH more reliable than diesel cooling systems (no exhaust elbow to clog)

Corrosion - Most sailing cats use aluminum sail drives. These are in the water constantly and are never flushed. It's not uncommon to see ones that have been in salt water for 20 years. Just change the zincs as needed.

Quiet - the outboards are much quieter and at the back of the boat. It's a joy compared to a diesel under your feet.

Lower health risk and pollution - Diesels emit a huge amount of NOx and particulate matter (PM) which contributes to smog and is poisonous to humans. It's estimated that 385,000 people a year die from cancer and other respiratory diseases related to diesel engine exhaust. The less you are around diesel engines the better it is for your health.

Efficiency - While diesel fuel has more power per gallon than gasoline, diesel mpg has declined with efforts to reduce emissions while gasoline engines do much better. And the outboard propeller is parallel to the waterline - far more efficient than the downward angled inboard propeller.

Less expensive - up to 200hp or so an installed outboards is about 1/2 the cost of a diesel engine installation. Not sure about the bigger ones.

[Whoosh]

Thanks for that, Carl...and interesting to this (mostly) diesel powered sailor. But there are some performance differences I will miss if shifting to gas powered outboards from an inboard diesel. One is the greater range for a given amount of fuel. These smaller boats that I'm researching can only offer so much fuel capacity. Add their higher fuel consumption and range is less than I would have hoped. Of course, the offsetting benefit is the speed a large outboard (or two) and planing hull makes possible. Which is why I'm digging into this option even tho' these are not strictly intended for extended cruising.

My other regret is the noise generated by these larger outboards, which is opposite to your thoughts. But I'm referring to outboards at planing rpm's while you may be thinking about smaller outboards at lower rpm's. My little 2-cylinder Honda outboard was like living with a Swiss watch...but all three of my diesel powered sailboats - when wound up to hull speed - were far easier to live with than a couple of 200 hp outboards, even with the cabin door back aft closed off. They are so noisy you can't hear most of the wave slap on a mildly choppy day.

Repair Costs? I'm not so sure about that. I've been watching Youtube videos with factory trained techs doing Yamaha service and it's been eye-opening. Basically, the surprise for me is how intricate the assemblies are, how many cautions exist for what to do (and not do) during disassembly and reassembly, the need for diagnostic judgements after disassembly, and of course the intervals themselves. I lived with my last diesel - a new Westerbeke we repowered with - for 9 years and 25,000 miles, mostly on my own. That experience was mostly about regular servicing, a small number of replacement parts with each service, and otherwise it was about fuel diligence & belt replacements. I'm getting the impression these newer outboards are full of surprises and wear shows up in all kinds of places. But...I'm not speaking from experience, so I'm tempering my thoughts on this for now.

Jack

[ranger58sb]

Originally Posted by Whoosh

... but all three of my diesel powered sailboats - when wound up to hull speed - were far easier to live with than a couple of 200 hp outboards, even with the cabin door back aft closed off. They are so noisy you can't hear most of the wave slap on a mildly choppy day.

I lived with my last diesel - a new Westerbeke we repowered with - for 9 years and 25,000 miles, mostly on my own. That experience was mostly about regular servicing, a small number of replacement parts with each service, and otherwise it was about fuel diligence & belt replacements.

You'd likely find higher-horsepower diesels in a boat in your target size somewhat different from the smaller versions you've had. Typical additions -- over and above size and basic horsepower -- would usually include inter/aftercoolers and a turbo... and then maybe some electronic control depending on how new you buy.

Just had to look up the size of that Jeanneau NC 895... since the name doesn't give much insight...

A typical inboard engine in a 30' powerboat might be a single or maybe twin gas, maybe 5.7L or so. But go a bit larger in boat size and on the secondary market, maybe 35-38, and you might start seeing diesels, maybe like the Cummins 6BTA (Diamond Series, 5.9L) or the Cummins QSB (Quantum series, same block/size, with electronic control) for examples in newer boats.

Probably much more noise (depending on boatbuilder and sound insulation) than you're used to, but likely no louder -- and maybe even actually quieter -- than your outboard examples. Maintenance would be pretty much what you're already used to, plus maybe a few more zinc anodes and maybe a little bit extra for periodic off-engine aftercooler service.

You might have a quick look at some of the "down east" style boats from makers like MJM, Back Cove, Sabre -- just as examples of inboard diesel boats that are semi-similar to (albeit slightly larger than) the Jeanneau you've reviewed.

And/or there are a bazillion pre-owned "express cruisers" from Formula/Cruisers/Sea Ray/et al that were made with some diesel options.

An afterthought: Note there's a difference between repair costs and service costs. It takes quite a bit of mis-use to cause a situation where a diesel needs and actual repair. And mostly periodic service is generally straightforward, easily predictable, etc.

-Chris

[wingssail]

Originally Posted by Whoosh

"If you are running 3 x 300hp engines, you will be at marinas regularly..."

Very true...but that's not the kind of boat we're discussing. I used Navionics the other day and did a route plan that had me leaving Biscayne Bay via Gun/Cat Cays and NW Channel light to Chub to clear, didn't refuel, hopped over to Nassau (did refuel) and then went out to the Exumas and gunk holed all the way down to Georgetown to settle in for a spell (and again fueled). This is the kind of limited cruising I'm referring to. I assumed the boat in the link above (good rpm vs. fuel burn data is available) and assumed a range of speeds (hull speed to low 20's at 1.5 GPM). With only two refuelings needed, it's pretty clear fuel in this case isn't the limiting factor. But there I am, in Georgetown and with two choices. I can backtrack all the way to Brown's in Nassau just in time to haul for my 100 hr service, or carry on what I'd really like to do by visiting Acklins again and then back southwest to more islands but exceeding the engines' service interval.

While these 100 hr service intervals generate repetitious expense, it's true this isn't a logistical problem while cruising within the U.S.. The puzzle is whether doing the typical wintertime cruising in the islands is feasible without distorting one's travels too much. Sadly, it is also likely that going even a little bit further - say over to Provo in T&C, let alone down to Luperon in the DR - just isn't feasible. Not one lift in that whole area to my knowledge, and tidal ranges aren't all that large either.

Jack

Jack without trying to duplicate your route plan, How many miles and how many gallons of fuel did you project?

And on the opposite side of the ledger, how many hours underway did you project?

[Sparx]

I have Yamaha T9.9s on a sailing cat. The only 100 hour service item on these engines is the engine oil, and a visual inspection.

Out cruising I change the motor oil on sharp 100 hour intervals, pulling the oil out through the dip stick. Takes 10 minutes per engine. I keep at least the next oil change on board at all times.

At a recent haulout I confirmed dip stick method leaves very little oil in the engine. I believe with a little technique development pulling the oil out via the dip stick will work on the larger engines too.

The lower unit oil gets changed at routine haul outs for bottom paint every other year. The gear lube has always been pristine when changed. It is probably possible the change warm gear lube from the top port, but I have not tried it. Doing this job with the boat in the water will take a little planning.

The rest of the service items are easily handled by removing the engine cover, and could easily be done with the boat in the water.

[smj]

Originally Posted by Sparx

I have Yamaha T9.9s on a sailing cat. The only 100 hour service item on these engines is the engine oil, and a visual inspection.

Out cruising I change the motor oil on sharp 100 hour intervals, pulling the oil out through the dip stick. Takes 10 minutes per engine. I keep at least the next oil change on board at all times.

At a recent haulout I confirmed dip stick method leaves very little oil in the engine. I believe with a little technique development pulling the oil out via the dip stick will work on the larger engines too.

The lower unit oil gets changed at routine haul outs for bottom paint every other year. The gear lube has always been pristine when changed. It is probably possible the change warm gear lube from the top port, but I have not tried it. Doing this job with the boat in the water will take a little planning.

The rest of the service items are easily handled by removing the engine cover, and could easily be done with the boat in the water.

We have the same two Yamahas on our catamaran as well. For the first time this year we changed the lower unit oil and impellers while in the water. We pulled the dinghy under the lower units and removed them from the engine. Changed the oil and impellers and reinstalled.
My friend has been doing this for years. I was reluctant but after doing it once I realize it was an easy process.

[Whoosh]

My thanks to Sparx and smj for their 'field reports', which are encouraging. But let's keep in mind the lower units of these 200 hp engines aren't just heavier but also more awkward to work with. The pick-up tube that runs from the impeller up to the head is quite a bit longer than the 9.9 engines while the raised 200 hp engine can only offer so much of an angle. And then there's all the bits to be removed and replaced, along with the need that the boat can't be bobbing around at all. I'm not saying an impeller replacement isn't impossible but it would be quite challenging and probably not something I'd try to tackle under those circumstances. To understand a bit more about that, watch one of the YT videos as a tech works it thru in the shop.

A piece of good news: the impeller needn't be replaced, unless there's an apparent problem, until at least 200 hrs of use. So assuming a fresh impeller before heading out to the islands, it doesn't enter into this puzzle.

Wingssails, I don't have the detail any longer. I do remember I flight planned the route out to Turtle Cove on Provo in T&C that I've done several times before and started via the channel just below Key Biscayne. The return from Provo got me to Brown's in Nassau, where a lift is available, at ~ 110 hours. The speeds were ~8 kts when at low rpms (~2000) and just over 20 when planing, tho' those opportunities were a minority. I realized after running those numbers that I'd omitted any engine time charging the house bank from the engines while on the hook, and I made no assumptions about the amount of solar I'd be carrying. (And probably missed more details, for that matter).

Jack