Volvo Saildrive 7yr service - jeepers!!!

[Elie]

I would be looking into some Perkins commercial diesel engines for that breed of Volvo engines.

[David M]

Originally Posted by MidLandOne

So far no problems.

NOW I know am just tempting fate saying that .

For reasons I have never followed up on Yanmars do not seem to be popular choices for smaller commercial vessels here, whereas a lot of Volvos (or if not those then into the more expensive breeds).

Yanmars are not popular for commercial boats because they do not have longevity. Too many ponies are being squeezed out of too few cubic inches. This requires them to be run at higher RPM's in order to keep the weight down for the same horsepower. Small boats are much more weight sensitive and do not accumulate as many engine hours so it makes sense to put Yanmars on smaller pleasure boats. They are also less expensive for a given horsepower.

Caterpillars, Cummins, Detroit and to some degree now, John Deere are the more popular engines. The distribution network is also a big factor. Engines that are out of service cost commercial boats lots of money in lost revenues therefore reliability is a huge factor. Commercial engines are also generally run harder and have more engine hours per year than yacht engines. The difference comes down to durability and reliability.

[MidLandOne]

Yes I believe you are likely correct David, although I haven't compared the rpms of equivalent Volvo and Yanmars. Made a point with our little Volvo to get a low revving one, ours is governed to max of somewhere around 2,800 rpm which is, of course, quite low for a reasonably modernish little 2 litre engine.

Probably the most popular engines for commercial vessels here in NZ are Caterpillar and MTU, and Volvo too for the planing lighter boats such as do fishing charters, etc.

Detroit Diesel have an excellent reputation but, of course, they in recent years went through contortions of combining product range with MTU in much of the world. Not many Cummins or John Deere here.

Don't think Detroit have been particularly well represented out here in recent years so not many in newer boats - just had a look on the local MTU/Detroit distributor's website and they don't seem to even list the venerable Detroits such as the Series 60 and give most space to the MTU side of the family. That I suspect because the land transport/industrial engine market is very small here but across the Tasman in Australia that is not the case, of course, with big mining industry, a lot of long haul trucking, etc.

John