BetaMarine or Yanmar. Which would you choose?

[rslifkin]

The key to an electronic engine in my mind is having the tools and info up l to diagnose it, knowing what spares to carry and making sure it's from a company with a good parts distribution network. And pick an engine from a model line with good history in commercial use of possible.

Think about how reliable fuel injection in cars and trucks is for the most part. It's not perfect, but it's far from the scary thing some make it out to be.

[Aethelwulffe]

I understand where you are coming from. Common rail is the primary issue, and ECM/ICM is secondary. Those common rail systems ONLY see improvements in light duty applications with varying loads, not what you see in a boat engine. You may pull in at idle, but when you are running, you want everything optimized for 2000-2400rpm cruise, and the engine is already set up for that. I am kind of one of those people that thinks electric nav lights are "nifty to have" though, and a paranoid minimalist.


1. I like a 12hp diesel better than a 50hp diesel, because I have a chance of starting it by wrapping a pull rope around the crank pulley if everything else is dead. Can't do that at all with an engine that requires electricity and a minimum voltage. Car is fine...boat on the windward short...no, I want the option. Better a working small engine vs. engine-shaped ballast.
2. Have not seen a dockside-drowned ICS module (or smart charger, or anything else with IC's or analog electronics) survive one time. I have drained, flushed and restarted one particular engine three times (really old wood boat). Do the stuff I do, and you will eventually get everything wet. I may have used an arduino board to build a CNC router, but I would not have a primary installed system on a pleasure boat that depended on it.

3. I love electronic control systems. They are great, and do a lot for automotive applications that replace electro mechanical ignitions and all those other wonderful advances. Different application. Purely mechanical diesel lasts a *long* time if run a lot, & I just want systems I can force to work no matter how it sparkles and pleases the control module. If it was a power boat, I would want the efficiency. Otherwise, I want tiny, simple, minimalist with a proven track record. Alternators are great too, but I prefer a DC generator motor for what I consider "hardened" applications.


That is just my basis for agreeing with the "Beta vs Novo Yanmar". Neither would be my choice, but this person's use case is obviously well known to him, and the choice of a drop-in solution is not to be ignored.

[Aethelwulffe]

Originally Posted by stormalong

I have to disagree with that. Engine spaces are hot, high vibration environments with the possibility of oil or water contamination. Electronics are not good in that operating environment. On the other hand the mechanical components of a diesel engine are all pretty large and engineered for that environment.

The most "delicate" parts of a diesel engine are the injector pump and the injectors. That is why they usually have two fuel filters and a water separator to protect them.

-and when you DO get bad fuel/air/gremlins you can crack every one of those banjos and bleed individual cylinders. Fix one and you can let it bleed itself sometimes. Common rail? Merely lose your lift pump (not to mention pressure pump) and you are totally toast. Three cylinder metering pump can go 1/3 bad, lose your lift pump, have to bypass your clogged filters to get a gravity feed pressure and you can still run the engine to limp in.



You can squirt a hose on the metering pump of a mechanical diesel (a cool one) all day, and the engine will start afterward and never know it. I can't do that even with my dear old Nissan Hardbody...the plugs would die quick, and the injectors/wiring may as well. Diesels don't really have the same type of EFI systems at all, but all the working bits are all contained inside an often pressurized housing. You get in via the fuel galleries, and that is it. A leaking plunger may leak fuel into the crankcase, but water won't go up the other way unless you sink in deep water.

Heck, I like centrifugal throwout starter bendix for the same reason. No solenoid living in the bilge. I just ain't as civilized as some folks, so ignore the primitive mindset.

[Old fella]

Originally Posted by Aethelwulffe

No matter what, the engine you can trust to be there when you need (whatever its other attributes) is the only one that is good. Most engines are pretty good...in the right application. If your system works, then to hell with changing it!

-All the same, it is nice to know you have an old Perk or Westerbeke when your lift pump dies in Honduras! I just can't see having to deal with major fuel issues at sea with a common rail. I don't want a little engine sitting in the bilge that needs electricity and a microcontroller for the CP3 pump and common rail pressure control to work. If you have a lot of hours on your Yanmar, it probably isn't a common rail. That is a factor when buying new iron.

You are dead right about common rail in a boat, and right again about my yanmar, it's a really old 2gm20 that just keeps on ticking on, (touch wood).if I had to re engine, I too would go for simplicity, less electronics the better. Sorry I was just pointing out, 500 hours and needing lots of parts, didn't have a good ring to it.

[Reefmagnet]

Originally Posted by Aethelwulffe

IMO...

100hp, 25hp, 35hp...None of it matters. Horsepower is...not a precise thing even when you are doing comparison. Torque curves; those are real. A 50hp 4cylinder and a 50hp 2 cylinder are radically different.
If you put a 100hp engine in a boat with a max clearance 16" prop and a gearing and pitch that stays under the max feasible RPM for a displacement hull boat, and you put a 15hp in the same boat with a 16" aperture and appropriate gearing and pitch, you find that the 100hp can get you to hull speed slightly faster than the 15hp, and uses a lot more fuel and air. That is about the only effect.
A typical 4cyl marinized diesel may be rated for 35-60hp. These are "torqey" configurations, put out the same watt values, but hp values are all over the place. They are equal to a 12hp DC PMM that *doesn't* need 75lb of flywheel to show high torque values on a dynamo. Those are not the important bits.
1. What is my best prop diameter for my boat configuration?
2. How much noise can I handle?
3. Do I want fine control with idle shifting, or do I want the boat to slam forward when I shift?
4. Do I want a efficient and lower drag 2-blade, or a more insistent 3 blade?

5. What pitch/rpm values for my prop diameter are ideal?
6. What are the minimum torque curve values on the input/output RPM range I can use to get the boat to hull speed?
7. What engine provides those values, and not greater than 10% higher?


The last one is actually very important. YOU DO NOT WANT to "light load" a diesel. You want to operate it to its design maximum output. Doing otherwise leads to a variety of issues such as Wet Stacking and...well, basically wearing out your engine because it never reaches full operating temps/tolerances everywhere it needs to. You don't want to "take it easy" on a diesel engine. People getting big alternators and running them at anchor should consider adding an autogen (and running an HVAC while they charge their batteries!) Running a diesel at 1800rpm for hours to do turn a 120 amp alternator at max output and put out ~ 1 kilowatt of actual draw (about 1.5hp) are kinda killing that big engine.

Having "reserve power" is also a false concept, because there are no hills to climb. Your prop sees the same water that has the same properties, and has the same traction and maximum power output no matter what. The only thing that can alter that is a CPP (controllable pitch propeller), and those are totally overkill for a sailboat.

Whilst I agree with much of what you have said, I'd have to disagree that having "reserve power" is a false concept. For two reasons.


The first reason is that speed of a vessel isn't a fixed relation to the rotational speed of a prop. This is easy to demonstrate. Motoring to, let's say, hull speed on a calm day requires less engine power than doing the same when facing into a 25 knot wind. To achieve hull speed on the windy day, you need to push the throttle forward. I suspect this is a result of Newton's third law and the logarithmic relationship of power required as propeller rotational speed increases.




Secondly, as the hull and prop fouls, or the weight of the vessel changes with load the same issue arises. Then there are things like high output alternators, refrigeration compressors etc that may be bolted onto the engine and these can suck a significant portion of the available power on smaller engines.


When I was reviewing the various literature for deciding on the new engine, I noticed that a figure of "30% reserve" over the calculated engine power required to power a displacement vessel to hull speed was noted for applications where "safety" is a priority in one of the blurbs.



I also don't think that running an engine lightly loaded for lengthy periods is as bad as it is often made out to be. Excessive idling will glaze bores for sure, but light loads? I'm not so sure about that. Plenty of generators run at light loads for many thousands of hours without problems. Diesel driven welding machines can spend 85% of their working life unloaded, and the other 15% at little more than 30% loading and these things can last forever. In all cases, a burst of load every now and again seems to keep them happy. In a variable speed engine, it's also important to run at varying loads and speeds to ensure that the cylinders don't develop a ridge at TDC as the bore wears. That can cause problems if one day you decide to push to redline and ring meets ridge!

[captchetco]

In my years as a chandler, Yanmar was much more difficult to source parts than Kubota. I opine that it may be because Kubota has much more commonality than Yanmar. Kubota parts cast way less and are easier to find. But my info is now 15 years old, 'cause I sold the chandlery, retired, and went floating.

[DeValency]

Both are great diesels and if you buy a new one and serve it by the book they will serve you for many years. I would go for the Beta (Kubota) as it is simpler, no electronics and made better for self sailor service. You need to check the access areas in your boat to important service areas such as oil filter, heat exchanger, raw water pump, injection pump etc. to determine which engine will assure a better access.

In my boat there is clear access from any side so it wouldn’t worry me. But at most boats this is the most critical issue.

Best of luck!

Originally Posted by Reefmagnet

Just have to face up to the facts. My poor old engine is too far gone to bring economically back from the dead. About to make a final choice between the Beta 30 or the Yanmar 3YM30-AE. The pros and cons are kind of balancing out for me, making it a toss of the coin so I'd just thought I'd throw it out there.


Which would you choose?

[MicHughV]

here's the thing....

back in the day...er..my day, that is, Yanmar wasn't making small diesel engines, Yanmar has been around since 1933....but their take on the modern sailboat diesel engine really only goes back around 20 years or so..so today they are the new kid on the block....kinda...sorta...
Perkins, Westerbeke, Volvo and several other makes were the sailboat diesels of the day, but there was no small Yanmar diesel that I can recall.

Then...enter the John Deere/ Yanmar marriage, too long to explain here.
About half of Kubota branded diesels is made here in Georgia.

Delving further into the matter one must also contend with Man, Caterpillar, etc...
It's a murky history....

Engine manufacturers are known for swapping parts and rebranding, etc, so it's really hard to say what is what or made by whom.

The venerable Harley-Davidson V-rod engine is made by Porsche...etc...

picking a Beta over a Yanmar or vice versa is a moot point. Either engine will give reliable service, if properly maintained.

[Wotname]

Originally Posted by MicHughV

here's the thing....

back in the day...er..my day, that is, Yanmar wasn't making small diesel engines, Yanmar has been around since 1933....but their take on the modern sailboat diesel engine really only goes back around 20 years or so..so today they are the new kid on the block....kinda...sorta...
Perkins, Westerbeke, Volvo and several other makes were the sailboat diesels of the day, but there was no small Yanmar diesel that I can recall.

.......................

OK please allow me to help you with your recall (in nicest possible way of course ).

Yanmar was manufacturing and selling good volumes small boat engines at least since the mid 1970s.

Their Y and S series was suited to the smaller boats of that era and although the QM series were more work boat oriented, many many QM's were fitted to sail boats.

The 1980s saw the introduction of the GM, HM and JH series all designed for recreational boats and all fitted to sailing boats.

Power ranged from 8hp though to 110hp with 1, 2,3 and 4 cylinders to choose from.

[MicHughV]

..I hear ya.....sales volume must have been low....
..in my early days of sailing...1980's onwards...I never once saw a Yanmar engine in a sailboat....not once...
..if they were around, they were not around in my neck of the woods...not then...
..I do know that Yanmar made some larger displacement engines for workboats, but in sailboats I never saw one back then...
...searching the internet, I find that Yanmar didn't really make an impact on sailboat engines until 1989 or thereabouts, when they were in competition, with, of all things...Kubota (Beta)..which jives with my recollection of first starting to see them in sailboats.
Kubota engines have been around for some time, often in a different guise.
You might recall.....back before time began...the Atomic 4...a gasoline powered sailboat engine....later replaced by Beta, which was just a Kubota, with another name.
When you talk about Yanmar vs. Beta, you can't have that conversation without also talking about Kubota..
Which is the best...I stand by my opinion, that with suitable maintenance, they both are..

[Wotname]

Originally Posted by MicHughV

..I hear ya.....sales volume must have been low....
..in my early days of sailing...1980's onwards...I never once saw a Yanmar engine in a sailboat....not once...
..if they were around, they were not around in my neck of the woods...not then...
..I do know that Yanmar made some larger displacement engines for workboats, but in sailboats I never saw one back then...
...searching the internet, I find that Yanmar didn't really make an impact on sailboat engines until 1989 or thereabouts, when they were in competition, with, of all things...Kubota (Beta)..which jives with my recollection of first starting to see them in sailboats.
Kubota engines have been around for some time, often in a different guise.
You might recall.....back before time began...the Atomic 4...a gasoline powered sailboat engine....later replaced by Beta, which was just a Kubota, with another name.
When you talk about Yanmar vs. Beta, you can't have that conversation without also talking about Kubota..
Which is the best...I stand by my opinion, that with suitable maintenance, they both are..

I must have been a trendsetter way back then

First sail boat (about 1981 - 30' steel) had a single cylinder front mounted exposed flywheel Arona badly installed - it was smokey shaky beast . Pulled it and replaced with a brand new Yanmar 2GM20. All my mates were using single cylinder Y series engines or the way heavier 2QM20w and were amazed at this "modern" lightweight diesel

Fast forward to 2000 and another boat (built in the 70s) which had a petrol (gas) 2 cylinder 2 stroke Stuart Turner (8hp) whose carburettor dripped more fuel into the bilge then ever went into the cylinders - scary stuff and not for the faint hearted .

Again replaced with a Yanmar 2GM20 but these days I would certainly go for a Beta for the reasons listed upthread.

Currently have a rebuilt 1975 Yanmar YSE8 ready to go into a project boat.

I guess regional influences have a big effect on what engines one sees in older boats. I'm told the SW of the UK was awash in single cylinder Yanmars in the last century but can't vouch for that!

EDIT: forgot to add that while I have seen a few Yanmars in older lifeboats, I have seen more Bukhs -maybe a marketing thing!

[Compass790]

Originally Posted by MicHughV

Which is the best...I stand by my opinion, that with suitable maintenance, they both are..

Agree that both seem to be good engines basically but..

Well I can tell you that locally a Yanmar ysm8 ( 8hp single diesel ) conrod is $630 about US $380

I dont know what the smallest Kubota conrod would cost but I can bet its a lot less than that

I suspect that Yanmar must be losing some market share to kubota based marine engines now as the flow of information is so much better than it was 25 years ago.

[Wotname]

Originally Posted by Aethelwulffe

Yeah, off topic.

If you can turn the shaft at X rpm, that being the maximum rotation speed and pitch within the available prop diameter before ventilation or cavitation occurs (both electrolytically damaging and essentially just making bubbles) with an engine, having a larger engine hitting the same RPM does NOT help "bash through". You have the same thrust no matter what.
More engine allows more even gear ratios, thus allowing for a potentially higher RPM, but if you hit max useful shaft speed for a given prop with the bigger engine, being able to turn higher prop speeds doesn't really do anything more.
To wit, the larger engine can allow a bigger prop, which is a design alteration, but in general, most boats are usually at their maximum dimension already. You can add blades and pitch with your bigger engine, but you still hit the point where your hull block/prismatic coefficient says "no more". I think that with 20kts wind available in essentially a heavy chop, I would probably be sailing my ass off with double reef and having a great time. If I needed to make way in a canal to pull in, I wouldn't have the chop issue, and almost any engine would get me to the dock (cheaply).



Going into a significant heading sea (mere 3' seas while blowing 20kts seems like inland waters), your SOG may suffer, but the STW that the prop is looking at is the same. More likely your SOG suffers from you being in a current at that point. In real slamming seas, higher momentary torque can re-accelerate you a little faster, but that means that your engine never otherwise gets a workout. Fact remains you have put the engine in an application where it is forever light-loaded. It is a primary factor in applications where engine x lasts forever in application A, and is a constant problem in application B.

If you are maxed out on thrust for a prop, having more juice available behind it does nothing. If you are underpowered to begin with, you can improve to the point where you can finally bury your bow into a 12' head sea and drown yourself. In the meantime, you will have engine issues. SeaForce9, a horrible oversized idiotic sportfish-cum-cigarette boat company shifted from using V16's to V24's with a slight corresponding prop change. The sale point was "We Upped our Horsepower, so Up Yours!" It is a planing boat, and they managed to increase top speed in flat water by about 2kts, but in a storm condition they are still lucky to maintain 5kts safely...same as everyone else. In the meantime, folks were faulting the new engine for reliability (and none of them have *any* hours to speak of). Same motors seem to have no issues in locomotives, but are too large for "switcher" engines that idle for thousands of hours every year. It is just impossible to load the output even close to the engine output with the available shaft angle.


Of course, this also applies to situations where a boat is over-propped because someone wants to hit higher speeds with a lower engine RPM. Torque curves of your engine output are important. Another ++ for electric drives.

Nothing to disagree with here however you must have a different understanding of "reserve power" means than me.

[MicHughV]

My introduction to sailing was on a homebuilt wood sloop that a friend knocked together in his garage, it was a Dutch design of some kind, plywood, etc....it was powered by a " Seagull" outboard of around 3 hp I think. Remember those ? A now relic British device.

Back in the late 70's, to own a sailboat, you were either very rich or built your own. I belonged to the latter group.

Homebuilt boats of my era sported a variety of diesels and gas engines...Lister....a one pot machine originally designed for farm use, plus a list of marinized farm or tractor diesel engines that were cobbled together by various home builders.

Depending on which country you were living in at the time, kinda determined what engines were available to use.

Yanmar was simple not on the horizon in my day. Did not even know the name back then.

I had another friend that built a ferro cement Pinky Schooner, originally powered by a Palmer gas engine of some kind, later replaced by a Pathfinder diesel, which I believed was sourced from a truck...

But, still no Yanmar back then.

I'm no diesel expert by any means. I've progressed from Volvo to Perkins to Westerbeke to Yanmar's, but have seen quite a few Beta's recently, usually as a re-power job, not a standard manufacturer install. Hard to say Beta without saying Kubota.

People that have the Beta installed, love them.

Modern day diesels are a far cry from the heavy weight, flywheel monsters of bygone days.

[JMaav]

I have Yanmar, but have crewed and cruised extensively with both engines. Although I have gotten pretty good at cobbling together parts for any engine, wherever I am... I always seem to find Yanmar parts... new, used whatever... and yes, at a price. I have even repaired Beta engines with some Yanmar parts... but, that might be my only reason to stick with Yanmar... unless your not an extensive cruiser. Ok, maybe not the only reason.. there are a lot of reasons to like both choices. But.. my experience is, the right part can usually be found for the Yanmar when you need it quick (or Sunday!) .