Reduced Power, Slow Mode ?

[droutte]

I have a 1989 Johnson GT150. I am pretty sure it is going into slow mode. I run it on plane for a few minites and will loose power, and will run on reduced RPM's (RPM guage is not working). I turn the key off, start it back up and it will run fine. <br /> It appears to happen just in rough water. I do not have any alarms going off. What causes it to go into slow mode & how can I troubleshoot it ?<br />It seems to run fine without a load, with the warm up lever up. For different problems, over the past two years I have replaced the stator, coil pack and power Pack. But still have this problem.<br /><br /><br />Thanks<br />Dan

 

[OBJ]

Re: Reduced Power, Slow Mode ?

The SLOW mode prevents the engine from operating over 2500rpm. You need to verify that. If it's not 2500 or something higher or lower....you probably got some junk floating around in one of the carb bowls. Rough water sloshes the crap around it gets stuck in a high speed jet. Stop the flow of fuel and it falls away.

 

[droutte]

Re: Reduced Power, Slow Mode ?

I rebuilt the carbs last year, and still have this problem. I am thinking a loose wire, or connection.

 

[Walker]

Re: Reduced Power, Slow Mode ?

Does 1989 150 have SLOW??<br />Check for overheating and check all ground wire connections.

 

[Dhadley]

Re: Reduced Power, Slow Mode ?

The 150 XP/GT's should have SLOW. One of the 2 temp senders will have 2 wires rather than 1.

 

[droutte]

Re: Reduced Power, Slow Mode ?

One temp sensor has one wire and the other has two wires. To check the sensors, can I disconnect them.<br /> Does anything else cause it to go into slow mode ?