We still have the original 28 year old Perkins 4-108 engine coupled to a Hurth 2.14 reduction transmission, right hand rotation. I service the mechanical components religiously, even when on cruises. I have either replaced or rebuilt many of the main engine components including the low pressure fuel pump, the high pressure injection pump, the injectors, the injector high pressure and return lines, the fuel line seals, the raw water pump, the oil seals, the alternator, the regulator, the heat exchanger, all the hoses, and on and on. Your engine’s reliability will be directly related to the care you give it. When I change the engine oil, I change the transmission oil as well. We use a dual fuel filter system, a Racor 2 micron water separator, and a CAV final filter. Both, in my opinion, are easy to service. Routine maintenance results in reliability. Here’s a photo of the Perkins 4-108.
Below is a photo of the Original Injection Pump prior to rebuilding; access is through a 10″ by 12″ cutout while almost standing on your head.
In the earlier photo you notice the Jabsco Raw Water pump, a very reliable piece of equipment; also very expensive to rebuild or replace. I rebuilt it once at a cost of $132 for parts alone, but the second time, 10 years after the rebuild, the shaft was scored. The kit plus the shaft came very close to the price you see above.Not a hard choice this time.
I replaced the entire exhaust system including the mixing elbow, all the hoses with Vetus hose, a new Vetus raw water Strainer, and a Vetus water lift muffler. The system is leak free, and the exhaust tone is slightly quieter.
My most recent improvement to the engine was the addition of a K & N air filter/ PVC system to replace the Perkins metal air horn. This new system delivers a softer air intake tone, and the increased air intake volume provides better crankcase ventilation resulting in far less oil seepage, a common annoyance for the 4-108.
When the rudder was out of the hull, I replaced the propeller shaft with a 30 mm Aquamet shaft and added a Gori 3 blade folding propeller. The original propeller was a 2-blade Gori racing propeller, and it had worn to the point where it rattled all the time. The process of selecting and installing a new prop was painful, costly, and still has not been resolved to my satisfaction. Gori’s engineering called for a 16.25″ by 10″, 3 blade, right hand propeller. Months after the installation I was still trying to sort out problems with the new prop overloading the engine. On a recent haul-out, I discovered that Gori sent me an 18″ by 10″ prop; the invoice says 16.25 by 10. As yet, Gori has not responded other than to say they will be happy to sell me new blades of the size they should have given me in the first place. I am not at all happy with Gori right now.