Engine hours are the figure buyers ask about most on a pre-owned boat. Read alone, they say very little. Their meaning comes from how the boat has been used and how it has been looked after.
Hours measure time and nothing else
The hour meter shows how long an engine has run in total. It doesn't show the conditions it ran in. An engine that has run at steady revs on long passages and one that has been started for short spells and stopped again can show the same hours. They are not equally worn. So we read the hours together with the boat's age, because how much the engines have run each year shows how the boat has been used. Long hours at idle go on the meter too, but they affect an engine differently from running under load.
Low hours
Low hours look good at first sight. But in an engine that has stood for a long time, the seals, the fuel system and the cooling circuit can suffer from lack of use. Sediment in the fuel tank is common on such boats as well. So we ask whether the boat was given protective maintenance while it was laid up. On boats that have been chartered, hours build up faster. In that case we expect the servicing to have been just as frequent.
High hours
High hours are not a reason to rule a boat out. An engine that has been serviced regularly, has complete records and shows nothing wrong on the electronic read-out can be healthy in spite of them. What we really look at is whether the major services laid down by the manufacturer were done on time. To see that, we put the manufacturer's service schedule next to the engine's hours. If a major service is coming up, we allow for it when we prepare the offer. If an engine has been rebuilt or replaced, the meter may have been reset, and we confirm that from the invoices.
What we look for in the records
We look at regularity first. Were the services done at the recommended intervals, or are there long gaps? Then we look at who did the work. A record from an authorised service agent, together with the engine's electronic history, is the most reliable basis. It is a good sign when routine changes of oil, filters, belts and the sea-water pump impeller show up in the invoices. We make a separate note of major parts that have been replaced and of faults that keep coming back. If the same fault has been put right again after a short time, its cause may not have been dealt with.
On a twin-engined boat, the hours and the service history of the two engines should be close. A marked difference can mean that one engine has been replaced or has had a major repair, and we ask the seller's side about it. The generator has its own hours and its own records. Much of your comfort at anchor depends on it, so we ask for those records separately.
If the records are incomplete
Missing records don't mean the boat is a bad one. We close the gap in other ways. An electronic read-out by the authorised service agent brings up the engine's running history and its logged faults. An oil analysis gives a laboratory finding on the inside of the engine. At the survey the engine room is examined in detail, and on the sea trial the engines are watched under load.
When we put the invoices in date order, the boat's maintenance calendar appears by itself. We also ask for the name of the firm that did the work, since missing invoices can often be supplied from its own files. The same goes for the generator. What comes out of these checks feeds into your offer or into your decision to accept the boat.
That is why we always read engine hours together with the records.
