Rough Cost to re build a Yanmar 4LH HTE

TimB1

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Hi all,
Thinking about buying a boat 15-16 years old. It has a Yanmar 4LH HTE in it with around 800 hours on.

It has been serviced regularly ( non main service agent )

Was wondering if worst case scenario occurred and the engine went bang, what would ROUGH cost of a rebuild be.

I will be getting the engine looked at by engineer prior to buying as well as a full survey.

But just wondering what I need to allow in my buying budget, for worst case scenario. I am allowing for other issues, but haven't a clue re engine.
 
If the engine went literally bang, it would be a new engine as block and head could be damaged. These engines should be good for 8 to 10,000 hours but lying around not working can be more of a problem with corrosion, bore glazing etc. In your case, the boat has only done about 50 hours per year. You should get an inspection by a good marine engineer and get an oil sample taken to establish internal condition. Also look at getting a full sea trial with the engineer.
 
Had one, good engine purpose built marine unit with pushrods so no cam belt. Check the heat exchanger caps for corrosion and leakage and I had some issues with a leaking water pump dripping water onto the pipes underneath and causing corrosion. It's an alloy engine so the five (if I recall) pencil anodes need checking and replacing regularly. Parts are pretty expensive and since it isn't a marinised digger engine like a Perkins I could never find non marine equivalents. Firefly on here is also well versed in these units. I think he had to replace a turbo once but that was due to some rusting while the boat was laid up for winter again if I recall. 800 hours is absolutely nothing of an age if it has been well looked after.

I don't think they are made any more so a big engine blowup means a new engine and a different one so brings in issues of different electrics, mounts etc etc a quick google looks like 20-25k just for the engine but I could be well out. I am sure marine engineers on here will give you a better feel.
 
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Had one, good engine purpose built marine unit with pushrods so no cam belt. Check the heat exchanger caps for corrosion and leakage and I had some issues with a leaking water pump dripping water onto the pipes underneath and causing corrosion. It's an alloy engine so the five (if I recall) pencil anodes need checking and replacing regularly. Parts are pretty expensive and since it isn't a marinised digger engine like a Perkins I could never find non marine equivalents. Firefly on here is also well versed in these units. I think he had to replace a turbo once but that was due to some rusting while the boat was laid up for winter again if I recall. 800 hours is absolutely nothing of an age if it has been well looked after.

I don't think they are made any more so a big engine blowup means a new engine and a different one so brings in issues of different electrics, mounts etc etc a quick google looks like 20-25k just for the engine but I could be well out. I am sure marine engineers on here will give you a better feel.

Agree with everything Stuart said, Good engine, parts expensive but when properly serviced will see big hours no issues. So long as serviced and well maintained 800 hrs is nothing.

Yes I had turbo issue, (still think that was due to not covering exhaust when out the water for 4 months) but rebuild done by very good turbo specialist just a couple of hundred quid.

Obviously you really are looking worst case scenario, get yourself a good engineer and most engine problems if they arise will be fixable well before you start looking at re-engine'ing.
 
Weak points on these engines are starter motors and heat exchangers. The heat exchangers are pretty expensive (I know - just replaced mine).

The block itself will die from lack of use long before it ever wears out.
 
I don't think they are made any more so a big engine blowup means a new engine and a different one so brings in issues of different electrics, mounts etc etc a quick google looks like 20-25k just for the engine but I could be well out. I am sure marine engineers on here will give you a better feel.
That is just about the rough cost of a new engine
 
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