Engine maintenance problems
That may have been true that the motor needed major maintenance every 5 weeks, but that was in 1980.
Today we have synthetic motor oils, and will be running on propane or natural gas which doesn't generate as much combustion by products to contaminate the oil. Also, in a stationary application, with a constant load, there is even less engine wear, as start up, accel and decel cause most of the wear in a car engine. I also think that 800-900hrs between maintenance is not at all that bad, especially if there is a significant reduction in the total energy bill.
It will also be possible to run an oversized oils sump to reduce total percentage of oil contaminents/unit volume. If with synthetic oils, the service interval can be stretched to 12 weeks, then it is ~4 times a year. A normal furnace should be serviced at least 1 time a year, so I don't think it is out of line.
Mike
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