New Engine

New Engine

We are writing this in the hope that you can give me some advise on a certain matter. Two years ago, we bought a Hartley Fijian 43" and we are living aboard in the port of Barcelona (Spain). Here, Ferro-cement boats are unknown and for this reason we are looking forward to the publication of the book "The Care & Repair". Our main problem is that, after many repairs, we must change the engine as it's broken. It´s a huge, old Perkins 6.305 marine diesel, 84 hp, 6 cylinders. We are unable to buy a new one, but according to our mechanic, it's possible to buy another Perkins 4 cylinders NOT marine very cheaply, and to convert it to a marine engine, using certain pieces of our old Perkins, (after a thorough service) and he would also install a gear box .

Alternatively, other mechanical workshop have told us that it is better to look for a marine engine with its gear box, because the other option above is possible but risky. Each mechanic says that his option is the cheapest. If someone could give us your opinion on which option is the best we would really appreciate it. Kind regards.


Hi Thomas, yes there are several options you can take, and from experience Spain is not the easiest place to for such an undertaking. Option 1/... Buy a new marine engine. Option 2/...Buy a new complete marinised vehicle engine, available from people like Lancing Marine in England and many others. Option 3/...Do-it-yourself or have an engineer marinise a vehicle engine. Summary/...option 1 is the easiest, but also the most expensive, not only the initial purchase price but also the cost of continued maintenance (marine engine components cost the earth, are only available from specialist suppliers, and the specialist marine engineers charge like dentists). Option 2 is also easy but less expensive. Vehicle engines for most purposes are entirely suitable and easy to work on by any auto mechanic. All that is required to marinise a vehicle engine is a marine gearbox, a heat exchanger, a water pump, and an exhaust manifold cooler. (Most heat exchangers are an exhaust manifold cooler combined). Some marine gearboxes require an oil heat exchanger for it, but they usually come as a complete gearbox unit. Option 3 is to buy a used vehicle engine and marinise it. Only rebuilding the engine if found necessary. As an auxilliary in a sailboat it would be highly unlikely that an engine would be required for more than 500 hrs in 10 years of service. That's not much more than a years use in a car or 3 months in a truck. Unless the vessel is a large working craft in continious use, a marinised vehicle engine is a good option for a requirement of from 30 to 150hp. For very small engines under 30hp, the specialist marine engines with integral gearbox etc are the best option. Finally, for a 'Hartley Fijian 43', a 4 cyl Perkins is really a bit on the small size. You need another six like a Ford series that are plentiful almost anywhere. You will then have another cost saving in being able to probably use the same propeller, as both engines are high speed diesels with similar optimum rpm. Remember that when considering 'hp', the actual power output or torque of an engine is also dependent on 'rpm'. A 72hp Gardner or Cummins is almost four times more powerful that a 100hp Ford 360 series engine. The former develop their max torque at around 1000rpm, whereas the latter doesn't develop it until around 3200rpm. Hope that helps. regards

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