40HP outboard stuttering

[crperryman]

I have a 1989 2-stroke that I've owned with my used pontoon for a couple of years. The previous owner deleted the oil tank and changed it to mixed fuel. Recently, it started stuttering above about 1/2 throttle, however when in neutral and revving the engine, it does not stutter. I replaced the plugs last year, and the ignition coils this past spring. I thought maybe it was a spun prop, so I replaced that - no change. Yesterday I replaced the fuel filter and pulled and cleaned/rebuilt the carbs - no change. Not sure what to check next. Any suggestions?

 

[The Force power]

I have a 1989 2-stroke that I've owned with my used pontoon for a couple of years. The previous owner deleted the oil tank and changed it to mixed fuel. Recently, it started stuttering above about 1/2 throttle, however when in neutral and revving the engine, it does not stutter. I replaced the plugs last year, and the ignition coils this past spring. I thought maybe it was a spun prop, so I replaced that - no change. Yesterday I replaced the fuel filter and pulled and cleaned/rebuilt the carbs - no change. Not sure what to check next. Any suggestions?

Sounds like a cylinder not firing under load
Inspect the Trigger & Stator wires for broken/poor connectors/connection
A timing-light is must have tool in your tool-box

 

[crperryman]

Sounds like a cylinder not firing under load
Inspect the Trigger & Stator wires for broken/poor connectors/connection
A timing-light is must have tool in your tool-box

Thank you. I tested the wires on the stator, and the blue set doesn't get a reading. Guess I need a new stator. I appreciate the quick response and suggestion!

 

[The Force power]

Thank you. I tested the wires on the stator, and the blue set doesn't get a reading. Guess I need a new stator. I appreciate the quick response and suggestion!

Before you start buying parts/throw money at it.
check out the following;
https://www.outboardignition.com/page20.asp

 

[crperryman]

Before you start buying parts/throw money at it.
check out the following;
https://www.outboardignition.com/page20.asp

But if I don't have any resistance on the blue set of wires, doesn't that indicate an issue with the stator? I checked before pulling the stator, and then again once I pulled the stator. Both times the blue came back with no resistance.

 

[crperryman]

I checked the trigger and stator with my volt meter. The trigger read good but I thought the stator didn't, so I ordered a new one thinking mine was bad. When the new one came in, I tested it before installing it, and it had the same readings as my existing stator, so I didn't swap it. I then decided to replace the power pack thinking it was my last option. Once it arrived and I installed it, the engine did up and ran smoothly. On the plus side, the carbs are now clean, the fuel pump replaced, and I've got a running engine! Thank you for your help with this!

 

[The Force power]

I checked the trigger and stator with my volt meter. The trigger read good but I thought the stator didn't, so I ordered a new one thinking mine was bad. When the new one came in, I tested it before installing it, and it had the same readings as my existing stator, so I didn't swap it. I then decided to replace the power pack thinking it was my last option. Once it arrived and I installed it, the engine did up and ran smoothly. On the plus side, the carbs are now clean, the fuel pump replaced, and I've got a running engine! Thank you for your help with this!

I'm glad I could help, Happy boating