Yanmar 3YM20 vs Beta 20

[Snowgoose35]

I need to repower and will get one of these - I can get both at so close to the same price that its not a decider and they have 1 hp difference in power and 4 ft lb more torque to the Yanmar but for 0.2L / hr greater fuel consumption - its a bit more fuel but again not enough to go one way or the other.

What really matters to me is a) reliability which reports show as very good for both and b) noise and vibration

I've watched video of both and its hard to see a difference but with mobile phone video sound is always poor so has anyone direct experience of both ?

I've heard people be very impressed by the smooth running of the Beta but can't find much about the Yanmar in this respect and my experience is only of the much older 3GM series which are very noisy and rattly - will the 3YM20 be better than the older ones?

Any feedback is gratefully received

[skipmac]

I would take the Beta any time over the Yanmar. Beta is based on a tractor engine, no electronics to run it, easier to get parts, better customer service.

[FlyingScot]

I'm a big fan of Yanmar. I would buy the Beta given a choice. Never heard any real negatives with Beta.

[Snowgoose35]

Originally Posted by skipmac

I would take the Beta any time over the Yanmar. Beta is based on a tractor engine, no electronics to run it, easier to get parts, better customer service.

What electronics are used to run the Yanmar 2YM20 ? It doesn't seem to have a black box like the bigger engines or have I missed something? That would be a major negative given how poor the latest Volvos have proven to be with all their electronic gubbins - I like stuff I can fix myself

[Scubaseas]

3YM20 is still a "dumb" diesel without an ECU. Regular old HP injection pump and injectors. Both are good but I would go with the Beta.

[ramblinrod]

Originally Posted by Snowgoose35

I need to repower and will get one of these - I can get both at so close to the same price that its not a decider and they have 1 hp difference in power and 4 ft lb more torque to the Yanmar but for 0.2L / hr greater fuel consumption - its a bit more fuel but again not enough to go one way or the other.

What really matters to me is a) reliability which reports show as very good for both and b) noise and vibration

I've watched video of both and its hard to see a difference but with mobile phone video sound is always poor so has anyone direct experience of both ?

I've heard people be very impressed by the smooth running of the Beta but can't find much about the Yanmar in this respect and my experience is only of the much older 3GM series which are very noisy and rattly - will the 3YM20 be better than the older ones?

Any feedback is gratefully received

Yanmar without any question. The design and technology is vastly superior to other brands. Many parts that are sand cast on others, are investment cast on Yanmars. You can’t kill them even if you try (almost). They have a huge marine dealer network. They design and sell tractor engines too but their marine engines are marine engines. Betas are a 3rd party marinizer. Yes, one can get Kubota tractor parts from a tractor dealer, as can they get Yanmar tractor parts for a tractor dealer. But one cannot get Beta parts from a tractor dealer. Note, the starter, alternator, and some other parts you may get from a tractor dealer, are not marine grade, and should be called in your next survey for replacement.

That said, I love the way Yanmars start and run. Reasonably maintained, a Yanmar with 5000 hrs will start in 0C /30F weather without complaint, where other brands, require glow plugs.

Yanmar dealers are often near the water, where tractor dealers often ain’t.

After many years of working on sailboat engines, I became a Yanmar dealer, because I admire them so. I only sell what I install, for an established customer (This post is not to solicit internet business, but rather advice based from a different perspective.)

We just purchased a used boat for our personal use that doesn’t have a Yanmar, and if it wasn’t perfect in every other way, including coming with a complete spare engine and transmission, I would have passed.

[ramblinrod]

One more thing, of the 20 or so Youtubers we follow religiously, the two who have repowered with Beta, Project Atticus and White Spot Pirates have had what I consider, premature unexpected engine problems.

Not needing replacement parts, is much more important than saving a few bucks in needed replacement parts.

[Supers0nic]

Yanmar in now producing the 3YM30AE. There are several upgrades from the previous model. I just had one installed in my 33’ trimaran. It only has 4 hours on it but so far am very pleased

[stormalong]

I am a happy Beta owner. I would suggest Beta because you will will be able to get Kubota parts anywhere. They are very reliable and well made. After about 4500 hours I have had very little maintenance needs.

Yanmar, which claims that their engines are designed for marine use has more limited parts availability and prices to match. I know that Yanmar also makes engines for small tractors but are the parts compatible and cross referenced? I don't know which Yanmar it is but one of their "marine" diesels requires the removal of an engine mount to change the raw water impeller.

[maine50]

Beta is set up to help self installers install their new engine. They can adjust the spread of the engine mounts usually to mean you don't have to change/fabricate new mounting beds. I think they are a better choice for the aftermarket customers. --Tim

[ramblinrod]

Regarding replacement parts, Yanmar has the widest dealer network for marine engines in the world....by far.

In the first 20 years or 5000 hours of ownership, if you maintain your Yanmar properly, all you should need is oil, filters, belts, impellers, and possibly a thermostat, all in stock and very inexpensive from your friendly neighbourhood Yanmar dealer, or favourite online discount Yanmar retailer.

I’ve heard lots of round the campfire stories, but I have yet to meet a Yanmar I didn’t like. If I had a choice of two boats to purchase, everything equal, but one with a Yanmar, the other a Beta, it wouldn’t take one second of thought to choose the Yanmar.

The installed base is huge. There are used engines and pard everywhere. I can often get rarely required replacement parts for a 40+ year old Yanmar, within 24 hours, maybe 72 if it has to come up from the US.

3 years ago, was about to pull the trigger on a 3YM30 for my personal boat, when I found a 1985ish Yanmar 3GMF, that I knew /respected the shop that serviced it its whole life. Snapped it up after the shop test, where the engine started for the first time in weeks, in what felt like a fraction of a second Before I actually depressed the start button. I have absolutely the same affinity for the 3YM30. They come standard on many major production boats in the 28 to 35 ft range. Great engines.

Re Stories of ECU lightning issues. Anyone here ever had to replace one? I didn’t think so. (The VP issue is a completely separate thing, grips design file followed by total incompetence). I feel for VP because employees with “P Eng.” after their name shoulda done better.

If any diesel 12 Vdc system gets hit by a direct strike, such as to hurt the ECU, there will be far more issue than just the ECU, like rings welded to the cylinder walls.

By the way, if a boat mechanic tells you that you need a new ECU due to a lightning strike, tell them you will need the old part to send to Yanmar for analysis. 90% chance there is no issue, 9% chance they will replace the bad one as a spare for you, if you ask nicely. (They are truly that great of a company.)

[a64pilot]

I believe a Beta may be indirect injected, and if it is, and if the Yanmar is direct injected. I don’t know if either is correct, but indirect injected Diesels are smoother and quieter than direct injected ones.
However direct injection is slightly more efficient, not so much to matter really, just as IDI is often quieter, but not hugely so.
https://www.hemmings.com/blog/articl...t-or-indirect/

If it doesn’t have glow plugs, it’s likely direct injected and if it does, it might be IDI.

[ramblinrod]

Originally Posted by a64pilot

I believe a Beta may be indirect injected, and if it is, and if the Yanmar is direct injected. I don’t know if either is correct, but indirect injected Diesels are smoother and quieter than direct injected ones.
However direct injection is slightly more efficient, not so much to matter really, just as IDI is often quieter, but not hugely so.
https://www.hemmings.com/blog/articl...t-or-indirect/

If it doesn’t have glow plugs, it’s likely direct injected and if it does, it might be IDI.

The Yanmar 3YM series incorporates common rail EFI technology. Vastly superior in efficiency, reliability, and emissions reduction. You will not see black soot from the exhaust of one of these engines, coating a white transom, even if overloaded (poor prop selection).

[Mike Banks]

A 3 cylinder diesel engine usually runs more smoothly than a two cylinder--so if vibration is a consideration I might source a 3.

I have a 3YM30 and it purrs.

[westwon]

I have had a Beta 20 in my Newport 30 for 5 years now. The install was easy, the engine starts easily every time, and the maintenance could not be easier. I absolutely love the oil change pump that is directly fitted to the engine, the ease of inspecting the heat exchanger tubes, the water pump location, etc. I'm sure the Yanmar is great as well, but I'm very happy with the Beta. Oh, and the after sales support here in Canada (Gartside Marine in Sidney, BC) is outstanding.


Steve