Carb Swap 20 Hp Johnson

fishpat

Recruit
Joined
May 3, 2013
Messages
2
Hello, folks
Been reading this forum for sometime now, found tons of great info.
Here is what I have going on, I own a 1989 20hp Johnson Long Shaft
I was going to buy a 25 or 30 horse motor.
I read that you can increase your power by simply swaping intake and carb.
I got brand new intake part#396788 along with a used carb Part # 432704
I tore down the carb cleaned it and installed new gaskets needle valves float etc....
Got it all togather, pretty simple to do!
My question is when I turned the tiller arm to wide WOT, I notice the throat plate in carb
kinda hard to explain, if you were looking at it from the side the top of throat plate would be at
2 o'clock, I am thinking it should be at 3o'clock, horizontal, when the tiller throttle is turn wide open.
Did not look at the old carb to see where it was for comparison, stupid me.
May not be an issue at all!
Just like to be sure its all good, going to take it out on the lake next week on Tuesday, to run the motor
that will tell me for sure, just thought you folks may have an idea or info for me.
Would be very much appreciated!
Kind regards
FishPat:)
 

jasper60103

Commander
Joined
Sep 18, 2008
Messages
2,055
Re: Carb Swap 20 Hp Johnson

Hello, folks
Been reading this forum for sometime now, found tons of great info.
Here is what I have going on, I own a 1989 20hp Johnson Long Shaft
I was going to buy a 25 or 30 horse motor.
I read that you can increase your power by simply swaping intake and carb.
I got brand new intake part#396788 along with a used carb Part # 432704
I tore down the carb cleaned it and installed new gaskets needle valves float etc....
Got it all togather, pretty simple to do!
My question is when I turned the tiller arm to wide WOT, I notice the throat plate in carb
kinda hard to explain, if you were looking at it from the side the top of throat plate would be at
2 o'clock, I am thinking it should be at 3o'clock, horizontal, when the tiller throttle is turn wide open.
Did not look at the old carb to see where it was for comparison, stupid me.
May not be an issue at all!
Just like to be sure its all good, going to take it out on the lake next week on Tuesday, to run the motor
that will tell me for sure, just thought you folks may have an idea or info for me.
Would be very much appreciated!
Kind regards
FishPat:)

Yea, the butterfly plate should be 3 o'clock at WOT. Sounds like a link & sink is in order.
Also, johny25 has a thread on this conversion. Keep us posted. Good luck.
http://forums.iboats.com/johnson-ev...rude-25hp-30-35hp-conversion-pics-532265.html
 

fishpat

Recruit
Joined
May 3, 2013
Messages
2
Re: Carb Swap 20 Hp Johnson

Where do I find info on how to do a link and sync info is greatly appreciated
Kind Regards
FishPat
 

bonzoscott

Senior Chief Petty Officer
Joined
Jul 26, 2008
Messages
745
Re: Carb Swap 20 Hp Johnson

Do a advanced search on this forum for "Link and Sink". For the most part, you'll find that you need an OEM service manual for your motor. But you may find some generalities on the procedure in the search.
 
Top