She looks very nice and clean and therefore well maintained.
The 2 GM is a substantial upgrade from the 2 QM engine. The engine block looks to be different as well as the cylinder head.
The 2 GM is definitely a newer generation of engine. I believe they are rated at 18 hp. The governor/fuel injection pump drive and housing is a whole lot better as well as the cooling water set up.
The GM is quite narrower than the QM which is great.
Look after that engine and it will out live you. 
Cisco.
Hi Cisco
I think mine (written on the plate at the front of the engine) is a continuos rating of 13hp at 3400 rpm
Regards Don
I think mine might just be a 2GM not a 2GM20 www.yachtdatabase.com/app/zmotorbrands.jsp
Different Engine specs are found on this website www.yachtdatabase.com/app/motorlist.jsp?id=Yanmar
Regards Don
A lot more variations on the Yanmars than I was aware of.
Very handy site that one. Thanks for posting.
Cisco.
Hi Cisco
Here www.marinedieseldirect.com/catalogs/ is another good site
If you click on the engine type it will take you to a online parts catalogue for that engine
Regards Don
This www.marinedieseldirect.com/catalogs/catalog.php?owner=mdd&model=2gm&manufacturer=yanmar&catalog=y00r0902 is actually the link I wanted to post as it is illustrated
I am sure if you work back from this link it will list other engine types
Regards Don
Select to expand quoteDonk107 said..
Hi Cisco
Here www.marinedieseldirect.com/catalogs/ is another good site
If you click on the engine type it will take you to a online parts catalogue for that engine
Regards Don
Thanks for that. 
