Yanmar Motors - How Many Hours?

[Jetexas]

There's definitely more threads here popping up regarding Yanmar problems than any other engine. Do you think that's due to so many more of them being in service than any other engine or because they have a higher rate of incidents?

I get the feeling that the internals of all brands of these little diesels are virtually bulletproof but that expense and availability of wear parts is the real factor when making a buying decision.

My experience with engines of all types is that frequent oil changes and preventive maintenance of the cooling system will keep them running forever without major repair.

[Captain Bill]

about 1300 x2. Yanmar seems to have two types of engines. Light weight ones that are rated 3600-3800 rpm, heavier ones that are rated below 3000 rpm. Pretty much any engineer can tell you that the wear and tear on engines increases dramatically with increasing rpm. I suspect that the higher reving engines might not go as long between overhauls as the lower reving ones. Interestingly while I have had no trouble with the engines, I have had some issues with the lower units/transmissions. I've also noted that Yanmar has gone back to the lower reving engine for their 40 hp saildrive. I wonder why?

[PaulM]

I have no idea how many hours on my 2GMF, It’s an 85' and runs great. I've put ~100 hrs on it since I brought it 3 years ago with a few small problems. Mostly maintenence. After following TSpringers saga, I feel very fortunate. And am saddened to know that there are butchers out there that call themselves diesel mechanics.

[Eric50]

Jetexas,

Here is an interesting point about Yanmar and their reliability and renown in North America.

In Europe, 90% (if not more) of the threads related to engine troubles are about other brands (mainly 2 brands, the most "famous" "V" and "P"...) than Yanmar and Yanmar is very well reputed through local leisure boat community, as well (which is more significant to me) as professional fishermen and harbour authorities.

On the other hand, I recently exchanged with a Canadian sailor that was up to start to build is sailing boat and had to make his choice for the engine.

I advised him to install a Yanmar of course, base on my own feedback and knowledge...and, to my great surprise, he replied me than in Canada, Yanmar where far away to be renowned as the best engines and would definitely not be his choice.

The guy was experienced as he used to run a motorboat he also built on his own previously (although it does not prooves anything, just to say he was not a newbie...).

So, it sounds that depending on which side of the ocean you are, the advises and opinion can be really different.

I do not know where this can come from (are Yanmar engines not only built in Japan but also in various other location, and this may explain some difference in the quality?).

Of course, this is based on very little number of subject and might not be valid as a generic rule.

I personnaly consider Yanmar as very good engines, mine (bought in Europe) is just perfect for its age, but I am not a skilled duly qualified mechanic engineer working all his life on marine diesel engines too...

It would be interesting to compare the feedback from both side to see if it is confirmed or not.

Best regards.

[Captain Bill]

I don't know if they're all built in Japan or not, but I can tell you that in the US it is not uncommon to be told that you'll have to wait three weeks for a common maintenance part because it has to be shipped from Japan. Yanmar NA customer support is crap in my experience.

[bstreep]

Our 4JHE has about 1900 hours. The boat has had a generator since new, therefore it is likely that almost all hours were for propulsion.

[Tellie]

Two 2GM2F over 10K hours each. Three new starters, one new heat exchanger, Various gaskets, two top end re-builds, four new exhaust elbows. Complete re-build scheduled for next year.


"Pretty much any engineer can tell you that the wear and tear on engines increases dramatically with increasing rpm." Captain Bill

I don't buy it. Perhaps a diesel engineer would say differently. Diesels are designed to run at their rated rpms for maxiumum life span. Low rpms in a diesel create a set of problems not incountered with gas powered engines. Also an important thing to keep in mind when dicussing marine engines, even ones taken care of is their run time. Many many marine diesels sit for extended periods of time without being run. Letting a perfectly good engine to sit without use can cause detrimental issues as well. The diesels engines that seem to fair the best are those that are run in their rated rpm
ranges and are run often.

[delmarrey]

So far the only part that I've seen built in Japan are the cone type transmissions. Every thing else on my 3JH4E is labeled from N. Europe.

I've had no trouble with parts but have with trying to get important info, which I've got from some of our gracious CF members! It seems Yanmar wants one to only use their qualified mechanics.

[Kefaa]

3GM30F on IP31 - 1428 hours. All original equipment except fuel filter system. All hoses, consumables, etc. being replaced over winter.

[rodney_k]

1997 4JH2E with 1189 hours. Propulsion only. No problems at all.

[JustCatamarans]

We deal with a lot of ex-charter cats that have the $jh and 3Jh series.
It is not uncommon to see them at 5000-7000 hrs and still going, bearing in mind that the engines are abused in the charter marker, whether running under max load, cold to full rpm running, and idling.
In my opinion they are the best kae of diesels, the parts are considerably cheaper than Volvo and easier to work on

[Chief Engineer]

In tears past I maintained Water Taxi engine (Yanmars)....replaced a lot of transmissions (due to azzwipe "captains") only one engine due to failure...they had
ten thousand hours plus on a few of them

[Solitude]

1400 hours on the 1gm10. Amazing little engine. Parts cost double in Canada than the US!

[Captain Bill]

[QUOTE=Tellie;401757]

"Pretty much any engineer can tell you that the wear and tear on engines increases dramatically with increasing rpm." Captain Bill

I don't buy it. Perhaps a diesel engineer would say differently. Diesels are designed to run at their rated rpms for maxiumum life span. Low rpms in a diesel create a set of problems not incountered with gas powered engines. [\QUOTE]

Tellie, maybe other brands of engines are designed to run at their rated RPM, but Yanmar recommends cruising at 85% of their rated continious rpm. My point was not that you should run diesels unloaded or well below the manufacturers recommended rpm, but that an engine designed to run at 3800 max rpm, 3600 continious rpm, and 3000 rpm cruise, is going to wear out faster than one rated at 3000 max rpm, 2800 continious, 2400 cruise.

[sigmasailor]

I agree, the lower the rpm the longer they last. In typical seagoing merchant ships they use diesels turning over at 100 max. 120 rpm for 8500 hours a year; those engines will last the life of the ship (@30 years that't's about a quarter of a million hours). Yes, we would change some valves,bearings, pistons and cylinder linings in those years.
The faster you run engines the shorter there life span. A typical drag race engine (the other end of the scale) will produce 7000 bhp at 10k rpm; 10 of those would power the biggest commercial vessels on the planet; for about a minute.....
Our boat diesels are in between those extremes; the general rule would still apply. The lifespan of an engine running at 2800 will be longer than one running at 3800 rpm.

I ran my 1.9 VW TDI engine (110 BHP) for some 7000 hours (320 kmiles) when the front left wheel broke off the car. Engine didn't consume any oil and was still super efficient (44 mpg or 18 klm/ltr). I do think they would make good boat motors.