1999 johnson 50.RPMs drop to 3500 for no reason

[DALEW]

Hello, I have a problem in that if I am cruising at around 4000-4500 RPM at times my engine drops down to 3500 RPMS by itself and the boat nearly stops. The prop is a little beat up and there is some vibration when it happens but I dont think it is a prop problem.Anywhere past 5000 RPMS and no problem. My motor has a S.L.O.W. warning system that, acording to manual, drops RPMs to 2500 when overheats. But if that were hapening wouldn't it alarm also? It was serviced before by the previous owner and the reciept says "sync and link repair".It was taken in due to hard start and poor indle. Thanks for any input. <br />--------------------------------------------------------------------------------

 

[JB]

Re: 1999 johnson 50.RPMs drop to 3500 for no reason

Hi, Dale.<br /><br />Welcome to the board.<br /><br />What have you done to try to isolate your trouble?<br /><br />Have you tried pumping your primer bulb?<br /><br />What do your plugs look like after one of these episodes?<br /><br />Let us know. We can do a lot more with more info.<br /><br />Good luck

 

[clanton]

Re: 1999 johnson 50.RPMs drop to 3500 for no reason

Check the VRO pulse hose behind the starter. Starter sometimes rubs a hole in the hose.