Here Are a few examples of the Identification tags you will find on your engine or generator. The underlined portions are the important numbers essential for proper parts lookup. Red is the Model number, Green is the Spec or Specification number, and the Blue is the Serial number. The serial number is seldomly needed for engine and parts identification.
This is a Model B48M GA018 With a Spec of 3423A. All of this information is helpful.
This is a CCKA With a Spec of 3718J
This is a newer 7000 watt Model HGJAD with a spec of C.
This is an older 12000 watt JC generator. Notice the spec number of 17687AB. This is important because it is one of the few that have two letters in the Spec number. The "AB" is important, Thats why you need to read the tag carefully and provide us with everything you see or might think you see.
B Series Engines- All of the B series engines originally came with either breaker point ignition or the less common magneto coil ignition, and electronic or 'breakerless' ignition was available as an add-on or option. To the untrained eye many people would insist that all of the engines that fall into this catagory are the same engine. They look similar and they do share many components from model to model. These engines have an aluminum block, and will have nine or 10 head bolts.
Performer Engines- Performer engines are the new version of the B engines. They all will have electronic ignition.
Linamar Onan Engines- Onan had the company Linamar manufacture their Performer engines for them towards the end of production. They are the same as the Performer and have coresponding model numbers for parts lookup.
Cast Iron Block Engines- These engines are some of the original Onans. They all origianlly had breaker points or the magneto coil for ignition. Very few had oil filters as it was just an option at this time.
Single Cylinder Engines- These were used on A small amount of mowers, generators, and floor buffers.
Old Generators- What you think is old and what we think is old may be different. We consider the generator to be an 'older' model if it has the cast iron engine with a 'square' or green painted perfect cylinder shaped generator back end. Generator components are getting scarce but not impossible to locate. These generators also often do not use a simple engine starter but start with DC voltage applied to the generator. (Easily identified by the quiet start up)
Emerald Generators- Probably the most common RV and commercial generator for a long time. It uses an aluminum B series engine or Performer engine. Depending on how old it is it may contain a heafty amount of electronics.
Newer Generators- Onan is still building generators but has decided to modify Robin Subaru engines for generator use. All parts and service must go through Onan as the engines are heavily modified. These units are highly advanced and have such features as Electronic fuel injection, Auto startup, Fully electronic governor controls, and onboard self diagnostics.
Diesel Generators- Onan has over the years used several common diesel engines with their generators such as Kubota, Isuzu, and Cummins. Parts are usually required to be ordered through an Onan dealer as Onan does modify and have special specifications for many parts on the engines.
You can snap a few pictures and e-mail it to Parts@enginemastersinc.com if you need parts.