Generator engines
Onan marine generator service and repair
Onan gensets are common on sportfish and motor yachts on this coast and they run long hours keeping air conditioning alive. I service, repair and load test them alongside main engine work, which is the sensible way to schedule it.
Onan on this coast
Frequently found on convertible sportfish boats and motor yachts, where a generator failure ends the trip even though the propulsion engines are fine.
What I see most on these engines
Cooling system fouling
Raw water circuits and heat exchangers foul with salt, causing high temperature shutdowns.
Exhaust elbow corrosion
Generator wet exhaust elbows corrode internally and can admit water into the unit.
Load capability
A generator that starts easily may still be unable to carry the air conditioning, which only load testing reveals.
Generator wet exhaust elbows corrode internally in the same way propulsion engine risers do, and a perforated generator exhaust elbow can admit sea water into the unit.
Factory certification is held with Volvo Penta. Work on other makes draws on 20 years of independent marine diesel experience rather than a manufacturer programme, and I will say so plainly if a job belongs with a dealer.
Services for Onan owners
Mechanical Marine Surveys
A documented condition report on your propulsion engines and generator, from visual inspection through sea trial.
Diesel Repair
Engine, transmission and generator service on marine diesels, from routine maintenance through a complete repower.
Engine Diagnostics
Find the actual cause before parts get bought, using engine management data, live readings and a borescope.
Other generator makes
Onan: common questions
Do you service Onan marine engines?
Yes. Over 20 years in marine diesel I have worked across effectively every make of marine engine found on this coast, including Onan. Call with the model and hours and I will tell you honestly whether it is a job I should take or one better sent to a dealer.
Can you survey a boat with Onan engines before I buy it?
Yes. A mechanical marine survey covers compression on every cylinder, engine management data, a sea trial under load and laboratory fluid analysis, regardless of engine make.
Do you carry parts for this brand?
Common service parts for the engines I see most often, yes. Model specific components are ordered once the fault is confirmed, which avoids paying for parts that turn out not to be the problem.
Tell me what the engine is doing
Describe the symptom on the phone and most of the time the problem is narrowed before I arrive. Surveys are booked around your sea trial date.