Rebuilding older Yanmar?

[newboat]

The Yanmar 4JH2E is considered by many to one of the all time great diesel engines-mechanical, non turbo-10,000 hours if taken care of.
If you gave one to a boat yard or a mechanics shop to rebuild it would probably get very expensive and not make sense. However, I agree with comments above that there is alot to be said for an "old fashioned"
mechanical (non computer run common rail) diesel for a cruising sailboat. If a rebuild of that great old engine does not make sense-you might consider a Beta replacement-also a simple, mechanical diesel and specifically marinized for the cruising sailboat market. I'll take your old engine for parts...I have a 4JH2E in my boat with less than 2000 hours and I just bought her new injectors for Chritsmas!

[Ken of KC]

Once you do determine if it needs rebuilt or replaced. You will have better insight to what it will take. You have not bought the boat as of yet, so another option would be to spend the money you would spend on a new engine and get a newer boat maybe.



I also would never let the local yard do the engine unless they had a pristine reputation for that kind of work with small diesels in sailboats, a power yacht is a different breed of cat altogether.



Since you can do the change out the hard work and long work is taken care of. Consider a professional engine rebuilding company there are many of them that specialize and have on the shelf the exact model you need and at about 1/2 the price of new. It also come with a warranty. They take your core and that keeps the price at about 1/2 of new and they have rebuilt many more engines than your local marina and they have the machine shop to do completely what needs done.

[skipperpete]

Originally Posted by massnspace

That engine website looks fishy to me….7K for a brand new Yanmar? In Indonesia?

Anyway, thanks for the input. Makes me think about a new engine, not rebuild…

More than fishy, Jakarta has had this scam going on in various disguises for years, I’ve actually contacted one of their fronts and looked at the maps images of their “outlet”. One of the iterations even had MTU’s available along with Betamarine, Volvo, yanmar , heavy duty DC electric drives etc. I was cuious about whether they were selling Chinese or Indian knockoffs or it was just a “no prodct at all” scam. I actually would have bought a cheap yanmar copy to open up and explore if it was fair dinkum. It was not.

[Icarus]

Nothing wrong with an older diesel engine if it's been serviced and looked after...an inspection by a mechanic would be helpful.
A 40 year old gearbox might be in need of replacing the clutch plates and bearings. unless it has been done before already.

I have a 44 year old 3cyl ISUZU on my yacht ...when I bought the boat the engine run fine, however, the exhaust water mixer to the water exhaust pot needed replacing...as well as the engine mounts. Some years later I had the head off and the valves and valve seats refurbished..as well as the fresh water pump replaced.
In any case you ought to be handy with mechanical issues.

[NevilleCat]

Originally Posted by massnspace

Not sure if you are serious or joking….

Having a (very) reliable engine when going anywhere (including offshore) is a no-brainer. Just sitting waiting for favorable winds, for example, is not really a great strategy. I guess you could take that line of reasoning to its logical conclusion and say “why have sails, just wait for the current to take you in, or for someone to see you and tow you in”….and who said I am only going into port every 4 weeks???

Of course even a brand new engine could fail. Yes. But why take unnecessary chances. I don’t travel that way.

My question about rebuilding remains…..

Plenty of people have sailed around without motors for years. Sure it's a pain if you don't have one. But we're not talking about that, you're talking about an old motor. If you expect it to not work for some reason and it's done more than say 5000 hours and it makes you feel better then, yes rebuild it or replace it. Most boats from the 80's will have been repowered or rebuilt by now anyhow.
Waiting for favourable winds, yes, and currents is absolutely a preferred strategy even with a "reliable" engine, and I would suggest that those who refuse to develop this attitude are likely to not have a great time.
The white flappy things with all the strings on the big stick are far more powerful and effective than whatever crappy overweight underpowered cast iron monstrosity lurks sullenly (but generally reliably) in your oil splattered bilges.

[Searles]

In kiwi a 4 236 Perkins or 4cyl 2700 series ford both peak at 80 hp at low revs,probably plenty re built in nz these engines just go for ever being tractor based plenty of parts universal .⚓️⛵️

[Windswept-windy]

My O2 cents.... Our plan, circumnavigation and currently in Fiji from Ca.

I have approx. 130K under my belt and read some time ago, your engine is number 1 safety piece of equipment. i.e. You are pinned to a weather side of an Island "cliff & rocks" something happens to the rig... you better have a very reliable engine so as to power out of that situation or other similar situations.

I have a 2000 Yanmar, (new to me) that has over 10K hours. It runs great. I have no idea how well this engine has been maintained. I'm lookn' at a circumnavigation... I need absolute reliability!!

Two choices....new engine or rebuild mine.
1.To purchase a new Yanmar....which is actually cheaper...buttt, it has to be electronic. Try and purchase a non electronic engine? Good luck! If it is electronic...who is going to work on it? I am a wrencher....I Need to be able to wrench on this engine...deep in the South Pacific if need be!! Not call a tech and connect a computer so as to trouble shoot!!

2. Rebuild what I have....needless to say, I took this avenue. I did pull engine & reinstalled. I did take it to my builder...explained my intensions in which he replied....I got ya!! I rebuilt my injection pump (turbo 4JH2-TE), replaced injectors, rebuilt tranny and purchased new engine mounts. Starter, sea water pump, stock alternator & Balmar Alt. all new. Also new heat exchanger and manifold as well. I'm just south of 20K

I now know exactly what I have... My foundation is solid. I can now, truly sleep well! JMHO

[Mickeyrouse]

There are a few diagnostics you can perform on any engine.
Get an oil test kit, most auto parts stores have them. It will analyze oil in the crankcase and , among other things tell you how much copper from the journal bearings is in there, or water from head gasket, etc. It will evaluate acceptable ranges.
Next, get a compression test. It should tell how the condition of the rings and valves are.
Then have the fuel injection system checked, injectors for pattern conformity and the injector pump itself.
If those test to acceptable ranges, the basic engine is likely sound, though appliances such as alternator, starter, raw water pump could still be iffy. You should carry spares for those anyway. Pressure test the heat exchanger at a radiator shop. Check for condition of all belts and hoses. Those age with an engine running or not.
The engine could be okay on those points, but may still be an oil leaker. Oil filter, pressure gauge fittings, oil pan, are all possible culprits. You could have an extremely reliable engine that needs oil added so frequently that it never needs to be changed.
Age alone rarely kills a properly maintained engine. An engine sitting up unused will have seals and gaskets dry out, hoses and belts dry rot, and rust form in cylinders that have a valve open- likely at least half the cylinders.
Replacing an engine has all sorts of unrevealed surprises if you’re going in with an engine other than an exact duplicate. I’ve found that out by experience.

[NevilleCat]

Originally Posted by Mickeyrouse

.....
The engine could be okay on those points, but may still be an oil leaker. Oil filter, pressure gauge fittings, oil pan, are all possible culprits. You could have an extremely reliable engine that needs oil added so frequently that it never needs to be changed.....

Bonus! I love the glass half full attitude here! 😉