The greenhouse Onan is a 10 KW generator.\\
From the plate on the generator:
  * Model 10CW-3R/1C
  * Serial 958526087
  * Data number: 10CW3C18  

This model was built between 1954 and 1966\\

For those who have a similar 10CW Onan here is the cross 
reference for the oil and air filters for this engine:

=== Replacement Oil filters: ===

Carquest 85010\\
NAPA 1010 (approx $10)\\
Fram C3P\\

=== Oil: ===

10-30W Detergent oil\
capacity: 6 quarts (or 7 quarts if changing oil filter)


=== Replacement Air filter (2 needed): ===

AC Delco A142C\\
Wix Filter 42371\\
Fram CA73\\



=== Recommended SparkPlug for 10CW ===
Champion K-15J which has been 
replaced by Champion D14 use .025 gap