20 hp Merc

[pgoddu]

Is there a source to determine what year my 20 hp o/b was built? I'd like to buy a manual (any suggestions on what's good and what's not will be appreciated) but first I have to determine what year it is. It came to me on a 1988 Whaler so I suspect it is that vintage. Is there an indicator reference in the S/N?<br /><br />Thanks in advance

 

[JB]

Re: 20 hp Merc

If you will post the s/n we can tell you, pgoddu.

 

[pgoddu]

Re: 20 hp Merc

OB 236859<br /><br />suggestions on manual???

 

[joblo33]

Re: 20 hp Merc

late 1987<br /> http://maxrules.com/graphics/merc_pdf/merc_pages_12thru15.pdf

 

[AMD Rules]

Re: 20 hp Merc

1987 20HP Mercury<br /><br />Mercury Service Manual per p/n 90-43509-3<br /><br />I'd strongly recommend the OEM manual rather than the aftermarket versions. Or get both

 

[pgoddu]

Re: 20 hp Merc

Thanks for the help...<br /><br />I've been told a carb from a 25 will fit the 20 - any sense of whether that's fact or fiction?

 

[AMD Rules]

Re: 20 hp Merc

Carb kits for the 18/20 1390- 8888A16<br />Carb Kit for the 25 1390- 8889A20<br /><br />It would "fit" , but they use different main jets & throttle valves.<br /><br />If you're looking to turn your 20 into a 25, there may be other restrictions in the motor design (exhaust/driveline?) Not sure.