Volvo is not one of our preferred choices for re-powers due to cooling system design: they tend to build in layers, more so than other makers, and the method of sealing is prone to leakage and corrosion to mating surfaces, ultimately this makes simple repairs both expensive and time consuming. Not being particularly unique to Volvo, most European designs seem to be more labor intensive to maintain and parts prices are higher then most Japanese derived diesel such as Westerbeke, Universal and Yanmar. In particular Bosch injectors found in Volvo, rebuilt injectors for most 1-4 cylinders engines took a price jump from $100 to $200 since last year from local rebuilders. Injection pumps prices are obscene.
We service and repair more older Volvo engines, more so, than the newer 2000 series engines, and we are seeing few new Volvo engines in new boats, which is not good for consumers over the long haul regarding parts availability.
The 2000 series has an exhaust mixing elbow mounted on top of the exhaust manifold, and the mounting gasket failure tends to let seawater drain into the cylinder if the gasket is allowed to go unattended. Moisture in the engine compartment allowed to settle on top of the engine has a tendency to cause the injectors to become rather stubborn to remove, yes it happens to all diesels, but more problematic with Volvo that uses copper selves to seal between the injector and head and subsequently the cooling water of the head; a frozen injector may result in a difficult removal situation, which in-turn may result in dislodging the copper sleeve which seals the head, this may make it necessary to remove the head for proper repair (expensive).
Of interesting note, your Volvo these days may not be a Volvo. Case in point, Our client bought a Hunter 45, the engine is clearly painted Volvo green, has Volvo stickers, it also sports a placard on the bell-housing which states "made for Volvo by Perkins." A closer looks, shows Japanese injectors, where Perkins traditionally uses CAV injectors, which further suggests the engine may have been manufactured in Japan for Perkins and in turn for Volvo.
Another cross channeled engine is the Perkins Parama, a Japanese derived long block. These came in a few Catalina boats for a while, bone shakers, if offered one of these run in the opposite direction.
With Yanmar, the company than not long ago proclaimed they build every Yanmar from the ground up directly intended for marine applications, has been selling for years the 6LP line as one of their own, a closer look by peeling off the Yanmar sticker on the valve cover clearly displays the raised aluminum name of Toyota, all castings also have raised letter clearly displaying the Toyota name (good engine). Yanmar has addressed this issue by redesigning the valve cover to now sport raised lettered Yanmar logo, therefore, keeping the myth alive. #
Yanmar if not smart, are at least attempt to be sneaky. In recent years had some problems with impellers designed for the 1 and 2 cylinder engines which had a problem with the rubber separating from the brass hubs, Yanmar claimed and maintained they had no problem with their impellers, however, if you had an impeller which did have this problem, they would be willing to replace it free of charge if you bring your damaged impeller to a Yanmar dealer; notice I didn't say "defective."
Another particular design flaw for Yanmar was the 2/3GM engine seawater cooling pump mounting and timing cover gasket problem. The seawater pump is installed with the cover plate facing the engine, making it necessary to remove the pump to change the impeller; the flaw is that the mounting bolts for the pump are also 2 of the timing cover mounting bolts, repeated loosening and tighten of these bolts contributed to timing cover gasket leaks. The timing cover gasket in itself, was also a source of gasket leaks; the early gaskets were pre-impregnated with a rubber ridge seal, claiming no sealant was required for assembly, these has a tendency to leak. Although Yanmar reported they had no problem with these gaskets, they redesigned the gasket to replace the rubber seal with an aluminum based product which tends to weld its self together, bet this will be fun to remove in the future.
Yanmar did however, if not take their sweet time in doing it, finally redesign the seawater pump installation with the impeller cover plate facing forward, eliminating the need to remove the pump to change the impeller in the new Y-Series engines.
Universal diesel engines are Kubota diesel based, their origin was agricultural and industrial long blocks, long known for simplicity, durability and reliability. Recent engine production has branched off into a separate marine line, no longer sharing agricultural and industrial blocks.
Westerbeke long ago had a rather questionable future as did most marine engine manufacturers due to limited availability of enduring diesel long blocks to marinize. In other words, they marinized anything they could get their hand on, but that has long since changed. Westerbeke now sports 3 products lines based on Mitsubishi long blocks up to 50 hp and 55 hp and up use the well established Mazada industrial block in the pleasure craft category. The third lineup is comprised of Isuzu industrial block in the Century Series engines aimed at the trawler, commercial fishing boat and heavy displacement sailboat market (geared to low RPM long running engines).
Westerbeke's recent acquisition of Universal was fill the horsepower range gap in the Westerbeke lineup and in some cases offers customer a choice between engines of identical horsepower with sightly different service point configurations.
Price wise, typically there is only $200 difference between Yanmar, Universal or Westerbeke; engine sales is a cut-throat market. All seem to be equally durable, all have their own quirks; choice these days seems to be based on perceived value, rather than real value, as all three will go the distance at comparable maintenance cost figures.
Food for thought,