oil to gas ratio seahorse 4.5 pk

[Ferry]

I have an johnsonseahorse 4.5 hp<br />model j5rc10<br />serial b002679 <br />what is the oil to gas ratio for this engine ?<br />does anyone know the year ?<br /><br />is there a way to "tune" this engine to increase horsepower ?<br /><br />greetz<br /><br />ferry

 

[Ferry]

Re: oil to gas ratio seahorse 4.5 pk

i made a mistake with the modelnumber<br /><br />the modelnumber is j5rc1c or j5rclc<br />its hard to see if its an 1 or an l

 

[JB]

Re: oil to gas ratio seahorse 4.5 pk

Hi, Ferry.<br /><br />Looks like a 1981 to me.<br /><br />Fuel mix is 50:1<br /><br />Good luck.

 

[Ferry]

Re: oil to gas ratio seahorse 4.5 pk

I found a site to "decode"the modelnumber and it turns out to be a 5hp.<br /><br />the numbers on the cover are 4.5<br /><br />where is that 0.5hp ?

 

[Chinewalker]

Re: oil to gas ratio seahorse 4.5 pk

It is a 4.5hp - the powerhead is actually based on the venerable 4hp, which was based on the old 3hp dating back to the early 1950s. Rather than put a 45 in the model number and really confuse things, they called it a 5, much like the 9.9's model number beginning with 10. After the power ratings were move from the powerhead to the prop the 4.5 was dropped to a 4hp by the late 1980s and called the "Deluxe".<br />- Scott

 

[Ferry]

Re: oil to gas ratio seahorse 4.5 pk

ok thx, now i know where the 0.5 hp is <br /><br />is it possible to tune the engine up.<br />i used to tune up my moped by making the inlet and outlet port bigger.<br />the only difference is that by the moped the carb was located on the side of the cylinder and not at the bottom like the outboard engine.