83 - 20hp-30/35 conversion

Rezonen

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20-30hp conversion

I got an 1983 20hp, J20BFLCTE

Can i convert this? Or does it have the smaller split gear case?

Does an 1990 30hp BE30EESS Carburetor and intake fit for the conversion?
 

Sea Rider

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Welcome to IBoats,

Will be able to convert a 20 to a 30 provided that both blocks shares the same CC to start with, for other parts compatibility must be compared and replaced if needed checking both models spare parts manuals...

Happy Boating
 

Rezonen

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Welcome to IBoats,

Will be able to convert a 20 to a 30 provided that both blocks shares the same CC to start with, for other parts compatibility must be compared and replaced if needed checking both models spare parts manuals...

Happy Boating
When comparing, does it have to be exactly the same model # on parts?
 

racerone

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The engine design came out in 1976.----All versions of this engine design were the same displacement.---It has been marketed as a 15 HP sail drive.( very small intake ports in cylinders ) and as a 35 HP before propshaft rating.-----The block is the same and the 20 hp motors for some years used a different carburetor.----Or the hole on the intake manifold is smaller.------Lower units on later 20 and 30 hp models is the same.-----I have one of those 15 HP blocks ( new ) on the shelf here.
 

Rezonen

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The engine design came out in 1976.----All versions of this engine design were the same displacement.---It has been marketed as a 15 HP sail drive.( very small intake ports in cylinders ) and as a 35 HP before propshaft rating.-----The block is the same and the 20 hp motors for some years used a different carburetor.----Or the hole on the intake manifold is smaller.------Lower units on later 20 and 30 hp models is the same.-----I have one of those 15 HP blocks ( new ) on the shelf here.
Okay, i just now checked on my engine and the 1990 30hp version, the carb and intake gaskets are the same, the pistons are the same, so it should work? There is no other ignition or anything else i should be worried about?
 

Rezonen

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The engine design came out in 1976.----All versions of this engine design were the same displacement.---It has been marketed as a 15 HP sail drive.( very small intake ports in cylinders ) and as a 35 HP before propshaft rating.-----The block is the same and the 20 hp motors for some years used a different carburetor.----Or the hole on the intake manifold is smaller.------Lower units on later 20 and 30 hp models is the same.-----I have one of those 15 HP blocks ( new ) on the shelf here.
I also now checked and it seems like the 1983 20/25hp is not the same gearcase as the 30/35hp one, the 20/25 one is split into 2 and the 30/35 is one piece. Should this be any concern?
 

Rezonen

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I now checked again, and the 1990 30hp has a primer solenoid, my 83 20hp has a manual choke, can i swap the choke linkage etc from my carb to the 30hp one?
 

racerone

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The choke / primer issue is a minor bump in your conversion.-----Just my opinion..-----Check and compare the gearcase on the 28 HP specials to see how it compares to your motor !!!
 

Rezonen

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The choke / primer issue is a minor bump in your conversion.-----Just my opinion..-----Check and compare the gearcase on the 28 HP specials to see how it compares to your motor !!!
Glad to hear, how do i go about solving it? Switch over my current choke linkage?

Do you got any model number on the specials?
 

racerone

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Easy in my opinion.----Go down the lists of motors till you come across the 28 HP special.----then compare powerhead parts to the 30 HP and compare lower unit parts to your 83 model motor.-----You will also learn during your searching.---I can't do it all for you without some beer tokens ---Sorry.
 

racerone

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When you learn how the electric primer valve works it will be an easy decision.----The electric primer was first used on 1980 models.---Used on motors from 9.9 to 300 HP for about 30 years.-----It is just a wonderful item when you understand how it works.
 

Rezonen

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I found another carb and intake now from a 35hp 80's model with normal choke, should be an easier swap
 

racerone

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Some will argue.-----I think the primer solenoid is a far better starting concept than a choke flapper.
 

tphoyt

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I’m with Racerone on this one.
It is an easier swap but not as convenient
The primer solenoid rarely fails and when it does it’s easy to repair.
 

Rezonen

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I’m with Racerone on this one.
It is an easier swap but not as convenient
The primer solenoid rarely fails and when it does it’s easy to repair.
Okay, if i get the carb that has the solenoid, should i tell him that i want the solenoid aswell?
 

racerone

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Explain exactly what you are asking.---.----There may be a solenoid on a carburetor that pulls the choke closed.-----The primer solenoid valve can be mounted anywhere under the hood ( or anywhere on the boat ) near the motor, with the hoses fitted.-----This primer solenoid valve is far superior to the choke flapper !!
 

Rezonen

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271046528_940581909895793_3940265209254539279_n (1).jpg

This is what the 30hp carb looks like. If i want this carb, i should tell the guy to sell me the carb+intake+solenoid as a "package"

Then i install it on my 20hp, and when cold starting i just turn the red lever, start it with rope pull, when it is started i just turn the red lever back and off i go ? :)
 

racerone

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The primer solenoid is for remote electric start application.-----The red lever is for manual operation of the primer solenoid should you have a dead battery.-----If you are only using a recoil starter you do not want the primer solenoid.-----There is also a manually operated primer valve that you can fit to the 30 hp intake and carburetor.-----Ask your supplier for that one.----He will have it I am sure.
 

Rezonen

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The primer solenoid is for remote electric start application.-----The red lever is for manual operation of the primer solenoid should you have a dead battery.-----If you are only using a recoil starter you do not want the primer solenoid.-----There is also a manually operated primer valve that you can fit to the 30 hp intake and carburetor.-----Ask your supplier for that one.----He will have it I am sure.
Okay thank you, i tried finding one online but couldnt find one, do you have any part # or name for the manual primer?
 
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