Loss of power on 1989 Johnson GT 200

[pokerface]

Ok I traded for a boat this winter with a 1989 Johnson GT 200 hp. When I got the boat the guy told me the timer base was bad and he could not get the flywheel off to fix it. So I got the flywheel off and in the process I found a parts motor, it was a 1990 Johnson GT 200 that was running but threw a rod. I took both motors to the shop and had them to just swap flywheel, timer base, power pack and stator. I put new champion plugs in it. Motor cranks and idles fine at home and on the water. I took it out and it would not get up on plane very fast so I called them back and he said it sounded like a fuel problem and told me the easy fix is to replace the primer bulb with a electric universal pump from 3-7 psi so i did. Yesterday I took it out. On the first pass it got up on plain quick but never seemed up to par. Then it started dropping rpm's. On my 20' Javelin the fastest it would run was 49mph. 5000 rmp was all it had then it dropped to about 4300. I came to a stop and killed it. Crank it right back up and it would not plain out for about 300 yards. I have checked the spark and it is good and no fuel leaks, compression is good. I have had problems with the wire going to the power pack that splits going to the solenoid not letting the motor crank. Any ideas? Bad power pack?

 

[levi_tsk]

Re: Loss of power on 1989 Johnson GT 200

rebuild your carbs - if it sat up for very long the ethanol go to em it only takes a couple of months to get gummed up with today's fuel
i dont know why they had you do the primer bulb bit before doing you carbs
id stop running it until i did btw youll blow that motor up if its not getting the right amount of fuel

 

[pokerface]

Re: Loss of power on 1989 Johnson GT 200

Ok I traded for a boat this winter with a 1989 Johnson GT 200 hp. When I got the boat the guy told me the timer base was bad and he could not get the flywheel off to fix it. So I got the flywheel off and in the process I found a parts motor, it was a 1990 Johnson GT 200 that was running but threw a rod. I took both motors to the shop and had them to just swap flywheel, timer base, power pack and stator. I put new champion plugs in it. Motor cranks and idles fine at home and on the water. I took it out and it would not get up on plane very fast so I called them back and he said it sounded like a fuel problem and told me the easy fix is to replace the primer bulb with a electric universal pump from 3-7 psi so i did. Yesterday I took it out. On the first pass it got up on plain quick but never seemed up to par. Then it started dropping rpm's. On my 20' Javelin the fastest it would run was 49mph. 5000 rmp was all it had then it dropped to about 4300. I came to a stop and killed it. Crank it right back up and it would not plain out for about 300 yards. I have checked the spark and it is good and no fuel leaks, compression is good, changed fuel filter and pressed choke at wot and bogged it down. I have had problems with the wire going to the power pack that splits going to the solenoid not letting the motor crank. Any ideas? Bad power pack?

 

[levi_tsk]

Re: Loss of power on 1989 Johnson GT 200

pull the plugs what do they look like ? are they wet ? if they are power pack or coils is suspect but im still saying rebuild your carbs if it sat for over a month or so
if the plugs are fouled id say it was carb job time
the fact that it idles good and cranks up good tells me its more than likely the carbs mine did the same thing

 

[jonesg]

Re: Loss of power on 1989 Johnson GT 200

That pump you installed should be set up so it stops if the engine stops but ignition remains on for a safety feature.
Like a roll over safety shut-off for the pump on cars.

 

[pokerface]

Re: Loss of power on 1989 Johnson GT 200

What gets me is that it will flood when I press the choke in at wot.

 

[j_k_bisson]

Re: Loss of power on 1989 Johnson GT 200

It is always going to do that. You have a electric pump with no pressure relief bypass. So when you open up the fuel primer circut, pushing in the key. It dumps tons of fuel into the running motor, flooding (killing) it. Get rid of the eclctric fuel pump. Go back to the manual one. You are flooding it when running over time.

 

[pokerface]

Re: Loss of power on 1989 Johnson GT 200

I still have the stock pump on there too. I unhooked the electric pump to see if it would make a difference and it didn't.

 

[dehydrated]

Re: Loss of power on 1989 Johnson GT 200

what size are the main jets? pull them and clean them up blow air through them

 

[Grassi25]

Re: Loss of power on 1989 Johnson GT 200

Just curious if you figured out your problem. I have nearly the exact same problem with a 96 200 johnson on a 20ft. stratos. Even had probs with the timing base. Not trying to hi jack thread just figured since I am having the exact same problem I would see if you ever found a solution.

Thanks.

 

[ranger1850v]

Re: Loss of power on 1989 Johnson GT 200

I'm not trying to hijack it either but I have the same problems with my 87 gt 200 on a old ranger boat. I've checked everything I know to check.

 

[metriccrescentwrench]

Re: Loss of power on 1989 Johnson GT 200

I'm not trying to hijack it either but I have the same problems with my 87 gt 200 on a old ranger boat. I've checked everything I know to check.

I'm guessing the folks in this thread have figured out their problems in the last year and a half and are long gone. Start a new thread, methodically listing what your symptoms are and what you've checked. (The first things you should check should be compression, spark, and see what the plugs look like).

 

[21ft Arriva]

Ok I traded for a boat this winter with a 1989 Johnson GT 200 hp. When I got the boat the guy told me the timer base was bad and he could not get the flywheel off to fix it. So I got the flywheel off and in the process I found a parts motor, it was a 1990 Johnson GT 200 that was running but threw a rod. I took both motors to the shop and had them to just swap flywheel, timer base, power pack and stator. I put new champion plugs in it. Motor cranks and idles fine at home and on the water. I took it out and it would not get up on plane very fast so I called them back and he said it sounded like a fuel problem and told me the easy fix is to replace the primer bulb with a electric universal pump from 3-7 psi so i did. Yesterday I took it out. On the first pass it got up on plain quick but never seemed up to par. Then it started dropping rpm's. On my 20' Javelin the fastest it would run was 49mph. 5000 rmp was all it had then it dropped to about 4300. I came to a stop and killed it. Crank it right back up and it would not plain out for about 300 yards. I have checked the spark and it is good and no fuel leaks, compression is good. I have had problems with the wire going to the power pack that splits going to the solenoid not letting the motor crank. Any ideas? Bad power pack?

Hi I know This is many years later but I have the same motor and having the same issues as you were can you tell me what your issue was?