Maintenance Generator Set
“Plug and play” is a popular concept in technology these days. An efficient generator married to a compact diesel engine can be plumbed to cooling and exhaust, fuel, and return in just a few hours. Plug in a single socket and you have the AC circuitry, battery charging, voltage regulation, system controls all connected instantaneously.
The problem with plug and play gensets say the folks who sell and repair them, is that they are so convenient, so reliable, tha some operators plug them in, turn them on and pretty much forget about them. No matter how well engineered, a complex piece of machinery operating long hours in a damp and dirty engine room is going to need a little attention.
Read the owner’s manual and follow instructions. Not all of it is intuitive. Maintenance on the little auxiliaries may differ from other engines. Maintenance schedules vary from one manufacturer to another, but a typical one calls for checking engine oil and coolant levels daily; checking valve clearance after the first 50 hours and every 600 hours thereafter; changing engine oil and filter, and secondary fuel filter, every 200 hours; checking and flushing the cooling system and changing the raw water pump impeller every 600 hours; and cleaning the heat exchanger every 2,400 hours.
One of the few repair jobs that the average user can do is replacement of generator rear-end bearings. They are in a sealed housing and can’t be lubricated, but the end plate can be removed and the bearings extracted with a bearing puller, available at auto supply houses. At about 5,000 hours bearing wear becomes something to check for.
Otherwise, unless you are a trained electrician there isn’t a lot of repair you can do as the operator. If you can read a wiring diagram, you can consult texts, such as Boatowner’s Mechanical and Electrical
Manual, by Nigel Calder, for instructions on diagnosing generator output problems. But remember, 120-volt AC can kill you. Do not attempt any diagnostics or repair on an operating generator unless you know what you are doing. Even when not in operation, capacitors on some units can deliver a fatal charge.
Follow the instructions in the manual, and your small genset should crank out a steady 120 volts at 60 Hz for around 8,000 to 10,000 hours. Bigger sets with industrial diesels, especially the 1200 rpm units, can be good for tens of thousands hours.
