Johnson Fast Strike 150 While planing slows and eventually will stall

[sublimebgd]

I have a 1995 Johnson Fast Strike J150GLEOM, while planing my bass boat today, the engine RPM slowed while I had the pedal at full throttle. The engine slowed while in gear until I was only able to operate at idle speed, if I tried to give it gas, it would hesitate to the point of stalling, almost as if something was preventing the engine from turning. The engine started right up and I can rev it all the way up to full throttle in neutral, no sputtering or anything, (the entire fuel system has been cleaned and rebuilt and I've had no issues). So I put it back in gear under load and after about 3 minutes of limping along at idle speed back to the boat launch I feel the lower unit engage and I can plane again, while on plane it does the same thing after about 3 minutes. Is there something that could be lose or misaligned here??? Or is it the gear shift?? This happened to me twice today and I don't want to start the engine back up for fear that there is something misaligned in the gearcase. I put the engine in reverse and stepped on it and the same thing happened, it is as if it's not going all the way into gear in both directions. The fact that the engine is stalling concerns me because it seems like something is preventing it from turning. Any suggestions would be much appreciated

[sublimebgd]

I have been doing a little research on this, is there any way it could be the shift interrupt switch?? I've seen later year Johnson engines with similar issues, not the same but the end result is the engine stalls, does anybody have any experience with this type of thing?

[Haffiman]

Disconnect it and test, but normally engine will not stall completely.