Data of manufacture

 Picture of the cylinder head,  did they look like this back in the days?

3792577 was produced 12-Jun-1990

Engine Type:ROTAX 912 UL

Model Number:309120010

( no additional information is found in the factory database...)

4407851 was produced 27-Apr-2006

Engine Type: ROTAX 912 UL

Engine Version: 912 UL2

Model Number: 309120010

Original Factory Configuration:

• without fuel lines
• UL2 I=2,27 with clutch
• for fixed pitch propeller
• without vacuum pump
• without mech. tachom. pick up
• without air box
• without external generator
• without engine truss
• without air guide baffle
• with std. temperatur sensors
• with nipple conn. for oil pump
• with expansion tank
• starter standard

You might also want to refer to  SB-912-057UL ...