Today, on our 340DA, my Koehler...

[Vinster]

Today, on our 340DA, my Koehler 5ECD ran perfect except when we used the micro. We noticed the lights in micro flickered, then tripped the micro breaker. Then, not using micro, We tried to use the stove, using both burners but that also tripped that breaker. We managed to use (1) stove burner, the AC, battery charger and outlets. All worked ok together. So, why when using the micro and then both burners, did those breakers trip ? I did hear the gen rpms speed up when load was applied, should be normal under load. Any ideas from my Searay Koehler friends ?

[wingless]

The generator rpm should remain constant, as the load changes, to maintain the 60Hz (US) or 50Hz (ROW). What will have an audible difference is the throttle / power automatically changing to deliver more / less output as the load changes.

To state the obvious, the breaker is tripping because excessive current is being drawn. That abnormal condition should not happen with the factory-installed devices.

A good place to start would be make a concurrent voltage measurement at the load while the load changes. The easy method would be to insert DVM probes into the spare NEMA 5-15 receptacle at the microwave and measure the voltage when idle and when the microwave is operating.

Those measurements should be the same, within about 5VAC. If not, then one potential issue is excessive voltage drops in the system. If not the same, then perform those same measurements within the generator, where the stator connects to the internal circuit breaker.

If the stator voltage remains constant, but the voltage droops at the point of load, then part of the distribution is bad and should be fixed. Move away from the stator, such as the other side of the internal generator breaker, then to the salon distribution system to discover where the voltage drops exist.

Note that when the voltage droops, the load is relatively constant, so the current must increase to satisfy the load. When that current gets too high it will trip the breaker.

Another option is that the breaker has gone bad. Use an ammeter to measure the load current to verify the current is normal and the breaker is tripping.

[Vinster]

Thank you for the diagnostics. After removing the air filter cover, the housing "insulation" all along the bottom, was full of engine oil. Inspection of the engine and gear case show no signs of an oil leak. I cleaned it all up and "dawn" cleaned the air filter. The oil level is full and I remain stumped. We started up the generator and put full load on it. The problem seems to be solved for now. Too easy a fix so I plan to run The generator for several hours on an upcoming weekend trip.

[wingless]

Thanks for the update.

Oil vapor can escape the engine from normal / minor crankcase blowby. Oil vapor then becomes oil when it contacts a surface.

It is typical for an engine to capture that blowby and burn it through the air intake, through a PCV valve or a hose ending near the air intake. It may be that system is obstructed and not operating properly.

These systems should be cleaned periodically, such as annually, to ensure proper operation.