Johnson Seahorse 20hp year and fuel mix

[Hunters of Bass]

I have just bought a johnson seahorse 20hp outboard model no: J20BFCIM and serial no: B007832. Can anyone tell me its year and where do i put engine oil into the outboard as i can't find the 'normal' place that i have previously. Also is the fuel mixture for this 50:1?<br />I also have a slight problem in that when the engine is running in a tank, it seems to idle ok but when the throttle is slightly opened up there is a sort of back pressure sound and the engine then cuts....does anyone know what may be causing this.<br />Thanks for your help in advance.<br />Mucho, Gracias!!

 

[rickdb1boat]

Re: Johnson Seahorse 20hp year and fuel mix

1981 - CI Fuel mix is 50:1. 1 pint TC-W3 oil per 6 gallons of gas. Sounds like it's running a bit lean at idle. run it on the lake and see how it does under some backpressure... The oil is mixed with the gas in the fuel tank.. Try to find a Manual for it or order one from the bottom of this page.

 

[Hunters of Bass]

Re: Johnson Seahorse 20hp year and fuel mix

Thanks for that rickdb<br />Is that 2 or 4 stroke oil?

 

[rickdb1boat]

Re: Johnson Seahorse 20hp year and fuel mix

2- stroke oil TC-W3 rated. Plain old 2-stroke oil will not work.

 

[Hunters of Bass]

Re: Johnson Seahorse 20hp year and fuel mix

Thanks again rick

 

[petrolhead]

Re: Johnson Seahorse 20hp year and fuel mix

We should really be careful with gas-oil ratio recommendations, remember that US Gallons and Pints are different (smaller) than the UK Gallons and Pints that the rest of the imperial measure world uses.<br />Don't whatever you do mix the two!

 

[rickdb1boat]

Re: Johnson Seahorse 20hp year and fuel mix

Very true, petrolhead. I should have said U.S. measurements. I forget that sometimes, but I figure if I say pints or gallons, you guys know I'm coming out of the U.S. measuring system. But thanks for the heads up... And I don't always look to see where someone is from...

 

[Hunters of Bass]

Re: Johnson Seahorse 20hp year and fuel mix

What does this add up to in English terms? American pints and gallons.....in English please?

 

[petrolhead]

Re: Johnson Seahorse 20hp year and fuel mix

A US Pint is 16 fl oz, compared to an Imperial (UK) Pint which is 20 fl oz.<br />Both US and UK Gallons are 8 US Pints and 8 UK Pints respectively.<br />Or to put it another way, 1 US Gallon = 3.785 litres, 1 Imperial Gallon = 4.546 litres.<br />Fine as long as you don't accidentally mix them up, can be confusing when you can't figure out why your US made fuel tank doesn't hold as much as it says it does!

 

[ob]

Re: Johnson Seahorse 20hp year and fuel mix

If all else fails 50:1 is 50:1 ,even on Mars.

 

[petrolhead]

Re: Johnson Seahorse 20hp year and fuel mix

I agree ob, far safer to just quote the ratio, what with different US and Imperial measures, and metric users who don't even know there's a difference, the potential for confusion and possibly expensive damage is enormous.<br />I like the Mars comment BTW, I always have that incident in the back of my mind when discussing this matter!