15hp help

supersoaker548

Petty Officer 2nd Class
Joined
Jan 27, 2013
Messages
103
my buddy just picked up a Johnson 15 hp elc start:D

i just cleaned the carp as it had some trash in it. from sitting and bad fuel line
my quistion is:
how can i tell what yr it is??
what should the A/F screw be set at to start with??? most motor's i have done are 1-2 turns out but this one was at 6.
it has no prop so what would be a good starting prop for this motor?? this is on a 16ft jon boat.

Thanks and i appreciate any and all help:happy:
 

kbait

Commander
Joined
Nov 13, 2007
Messages
2,471
Re: 15hp help

I assume it's newer than '74. I use a 4 blade 9 in. pitch Solas brand prop on my wide/deep 14' alumacraft and it's awesome. Bought it right here at iboats at a great price and quick ship!

Go here w/your model number and find year: Johnson Outboard Motor model numbers and code

A/F screw? If you mean the low speed mixture needle, start out at 1.5 turns out from gently seated and adjust from there.
 

supersoaker548

Petty Officer 2nd Class
Joined
Jan 27, 2013
Messages
103
Re: 15hp help

Thanks kbait.. yes on the LS needle:) as i thought someone has tryed to get it to run and had the screw way out.
I ran out of day light and it got to cold to look anymore:( did not find the Model or Serial plate any where:(

is there a disc on the motor like a Mercury has that will have a # stamped into it???

will tell him about the Prop and get it ordered asap Thanks
 

FishinDave

Seaman Apprentice
Joined
Jun 12, 2012
Messages
46
Re: 15hp help

If you dont have the data plate(information plate) on the side of the motor mounting bracket, you can put a picture up here and we can tell you. If you have the data plate, let us know what the model number is and we can tell you. To me a prop is a prop on a small outboard as long as its the right one. They make them with different pitches for torque and speed but its preference. As for the A/F screw im not 100 percent sure on the turns but six seems a little to much. What i usually do is turn the screw all the way in(not tight but just until it barely stops), then turn it open one full turn and try getting it to run. If it does not start up, turn it out another half turn and continue to trying to get it to start up and run. Once i get it to run slightly, I begin to feather the choke to keep it running and at the same time i continue to adjust the screw by a quarter or a half turn out until i do not have to feather the choke to keep it running smooth. There may be a better way but this works.
 

supersoaker548

Petty Officer 2nd Class
Joined
Jan 27, 2013
Messages
103
Re: 15hp help

Im going to take another look in the AM to see if i can find the plate. If i come up empty i will take some pics and post.

This is my 2nd outboard that i have worked on . I just did my merc. 40 4cyl with 2 carbs and it truned out Great runs like a top :) thanks to the guys on iboats forms /:>)

i have done a lot of 4 stroke motorcycles, atvs, and v8 boats and car carbs :) so far these outboards seam about the same .
you start with the A/F screw at about 1 to 1 1/2 turns out from light seat.
on these carbs you are adjusting the air flow and not the fuel flow. ( I think ) IE... the vac. that pulls the fuel thur the idle circuit

i adj. mine 1 of 2 ways
if i have a vac. port i adj to best vac. then richin it 1/4 turn
no vac. port i adj rich tell it just starts to stumble then lean tell it just starts to stumble then set in the middle :) and most of the time it works to too run it rich tell it stumbles the lean it 1/4 turn

this may not be the right way but it works Great for me:) for mild motor,, and i do a finner adj for my HP motor ....Like my jet drive it has around 680 hp BBC 548cid w/ 1050 dom carb 4 A/F screws
 

supersoaker548

Petty Officer 2nd Class
Joined
Jan 27, 2013
Messages
103
Re: 15hp help

i found the # disc on the motor and looked it up :) thanks for the links Model #J15ELEDS Ser. # G04087476

it's a 96 15hp 20in shaft elc start

does anyone have a book on this motor that can tell me the order and specs on setting the engine timing and carb timing ???
 
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