Have these Yanmar Diesels a good reputation for reliability

[boeing1]

have worked on several boats with yanmars engines, it really depends how they were maintained, and for cost of parts search the internet, for the best prices. I do not think they cost any more than other makes of engines.

[emcmia]

I corroborate all the positive comments. My 1993 cat was originally fitted with 3JH2E (38hp) Yanmars. After 5,000 running hours, I replaced them with new 4JH3E (56hp) in 2000. Given the excellent condition of the 3JH units, I received more than 60% trade-in credit off the price of the 4JH engines. Other than the oil pickup tube breaking off the block in one of the later engines, my experience with these engines has been exemplary. Have had no issue with parts availability (in SE USA, Caribbean, Mexico) and many aftermarket parts (e.g. alternators, starters, oil and fuel filters, etc.) are readily available at a fraction of the price of Yanmar labels. Regular and frequent changes in lubricating, gear and cooling liquids are highly recommended for any diesel - regardless of running hours and make.

[hrsek]

Installed a Yanmar 2Ym15 6 years ago - could not live without it!

[Kiwi.]

I was a director of the New Zealand distributor of Yanmar for many years (no involvement now) and I can say with certainty that the 4jh series of motors are very reliable. We never made much money out of the spares for them because they hardly ever broke down.

[Kiwi.]

Many other OEM manufacturers use Yanmar diesels in their products. Mase Generators (Italy) is an example. Spare parts can often be purchased from their agents at very good prices. A lot of refrigerated long haul trucks use Yanmars as their fridge motor. I've seen these motors run virtually continuously for four or five years at 8000 hours per year, that's 40,000 hours.

[Celestialsailor]

Originally Posted by Kiwi.

I was a director of the New Zealand distributor of Yanmar for many years (no involvement now) and I can say with certainty that the 4jh series of motors are very reliable. We never made much money out of the spares for them because they hardly ever broke down.

Having your direct involvement in the distributorship of the Yanmar, would you say that Yanmar had a good representation in Europe?

I know one thing...When I had that crappy Volvo 2003, 27hp motor, that starter was over $600 in 1993. I priced a Yanmar starter in comparison and it was well under $300 if my memory is correct.

I have a Westerbeke W46, based on a Mitsubishi 4DQ5 tractor engine. When rebuilding it Westerbeke wanted $1200. for a gasket set...Mitsubishi, $250 for the same set.

[Kiwi.]

[QUOTE=Celestialsailor;2014251]Having your direct involvement in the distributorship of the Yanmar, would you say that Yanmar had a good representation in Europe?
QUOTE]

A few years ago I was at a conference at Yanmar European headquarters in the Netherlands when they announced that they had over 1500 dealers in Europe. They seemed to have people at the conference from every significant port and city in Europe there. Here's a link to their dealer locator: https://www.yanmar.com/global/dealerlocator/

[Capt.andiamo]

I replaced my 30 year old Perkins with a yanmar and love it. Starts first time every time. You should always have spair parts like belts and implors on board just in case. The cost on these are reasonable.

[Wotname]

Originally Posted by Boxertwinjeff

Hi, a boat I will be looking at soon has a 50hp Yanmar diesel, Model 4JH2Ce, don't know what year it was built, Owner says it was completely rebuilt in 2012 and has 645 hrs up. From photos & a survey report it appears to have been well maintained. Are they a good reliable engine?
and any ideas to what year it is? thanks for any replys...

I note you are in Qld so FWIW, Yanmar operates a pretty good dealer network in Oz.

In addition, Minards near Newcastle offer a word wide delivery of Yanmar parts. I have dealt with them a few times and have always found them true to their word. AFAIK, they are not part of the Yanmar authorised Aussie network of dealers but they know their stuff especially with Yanmar. About Us : Minards Diesel

And yeah, the engines are as good as any, if not better than most - IMO.

[Celestialsailor]

[QUOTE=Kiwi.;2014276]

Originally Posted by Celestialsailor

Having your direct involvement in the distributorship of the Yanmar, would you say that Yanmar had a good representation in Europe?
QUOTE]

A few years ago I was at a conference at Yanmar European headquarters in the Netherlands when they announced that they had over 1500 dealers in Europe. They seemed to have people at the conference from every significant port and city in Europe there. Here's a link to their dealer locator: https://www.yanmar.com/global/dealerlocator/

That make more sense. I think it was the 2nd. post on the thread stating from hearsay that parts were hard to find. I didn't think a huge diesel engine manufacturer would be heavily supplied in the US and no Eur.

[waltdrechsler]

Funny, Yanmar was one of the top must haves on my list for our new boat. Very dependable and parts may be a little more expensive but quality usually is. Have an oil sample analysis done. If that doesn't satisfy you, have a survey done on the engine.

[Boxertwinjeff]

Originally Posted by hamburking

Do you have any reason not to think the engine is the same age as the boat?

Any receipts or proof of rebuild?

Boat was built in 1978, I've since learnt from the owner that the
engine was installed in 1999, "rebuilt " in 2012 so that's 13 years
before rebuild...does that sound too soon all things being equal?
If so, maybe it wasn't maintained very well by the original owner...

[Wotname]

Originally Posted by Boxertwinjeff

Boat was built in 1978, I've since learnt from the owner that the
engine was installed in 1999, "rebuilt " in 2012 so that's 13 years
before rebuild...does that sound too soon all things being equal?
If so, maybe it wasn't maintained very well by the original owner...

Way too soon IMO unless, of course, he was doing 2 or 3 hours a day, every day!

Sounds more like poor maintenance and he allowed the engine to swallow sone water or somesuch. Can you find out exactly what was "rebuilt"?
The parts usec would be good start and could tell us something useful about what was done!

[Dockhead]

With apologies to Lizzie Belle, I think she’s confusing Yanmars with certain models of Volvo.

As you can see from the posts above, Yanmars, especially the 4JH’s, are widely beloved, so certainly no reason to reject a boat.
I have experience with Yanmars, Perkins/Westerbeke, and Volvos, and call tell you the following:
There are actually very few bad boat diesels made in the last 30 years. One particular model of Volvo gave a lot of trouble 20 years ago, which has hurt the reputation of Volvos, but most Volvos are absolutely fine. The engine is almost never the source of problems on board except in case of operator error or failure of the marinization parts, water up the exhaust, etc. So other than one particular model of Volvo, the make of the engine is just never a reason to reject a boat, assuming we’re talking about relatively modern boats with diesel engines.
Yanmars are the only boat diesels where both the engine and all the marinization systems are made in-house. So the engines are actually purpose built for marine use, which might be some kind of a plus.
In my opinion, Yanmars, at least, 4 cylinder Yanmars, have the following pluses and minuses:
PLUSES:
Very smooth running, quiet, sweet sounding
Very easy, reliable starting
Light weight
Very reliable
Easy to work on (especially, because marinization parts are well integrated)
Widely available parts and service

MINUSES:
Reputation for being smoky, although not all of them suffer from this
Parts expensive (but not as expensive as Volve)
Not as simple as Nanni, Beta

The 4JH’s are fast running engines, with redline near 4000 RPM for some of them, which some people consider a disadvantage, but I don’t see any big problem with that.
The fuel injection systems – the most sensitive component of a diesel engine, by far – are top notch, made in Japan by Zexel, known for better quality than the Bosch systems used on other diesels.

Parts are a double-edged sword. They are fairly expensive, but not as expensive as Volvo. Yanmar has a strict monopoly system which protects territories of parts dealers. This makes it impossible to find discounted parts. But they seem to require their dealers to carry significant stock (I guess tit for tat for getting a protected territory), so availability of parts is very good.

Yanmar dealers and workshops in almost every significant port worldwide.

Someone above suggested buying the Yanmar impeller removal tool – a hearty second to that. The seawater pump is mounted backwards on the 4JH without clearance between the pump and the starter to get a regular impeller puller in. It is extremely difficult, maybe impossible, to get the impeller out without the special tool. The clever tool is very effective and surprisingly cheap.

[Boxertwinjeff]

Originally Posted by Cheechako

I might wonder why it had to be rebuilt already...?
Is that engine a turbo? I have seen complaints on forums about those.
Pretty much all marine diesel parts are expensive, not just Yanmar.

On further questioning of the owner he says it had 4200 hours up
before the rebuild, apparently Raw water siphoned through the exhaust manifold and into the engine,...he says caused by poor design of the
anti siphon valve, original design was a chamber above waterline with a
breather going down to the exhaust mixer box. He replaced it with an
an syphon valve positioned well above the water line....his words.
Since salt water has inundated the engine would it now have a much
more limited life and should I avoid it ?
He will get back to me with a list of replacement parts and what exactly was done in rebuilding.