1996 Ocean Pro fades away when hot

My Ocean pro 150 will peter out when it gets hot. Fuel system is OK, clean, no leaks, no air leaks, no pipe pinching, when engine stops primer is still full. I have removed thermostats to try and achieve colder running. Problem still occurs but later. I have added oil to mix to see if this would reduce temp further and help;it does but only a little. VRO works fine based on consumption. Engine will run for 1/2 hr then cut to zero in 5 secs. One curious thing; if i trim motor while running, engine misfires. I have been told that fitting Champion plugs may help, I use NGK.I have also been told that some electrical connections may open when tbney get hot. This engine is winterised properly each year and does around 60 hrs/yr. Servived in spring throughout. My sanity now at risk...

Re: 1996 Ocean Pro fades away when hot

I would definitely use the Champion plugs. I know this sounds rudimentary but are you getting a steady stream of water out of the telltale on the back of the motor? Also check the operation of the temp sensors in each head. There should be a tan wire coming out of each; disconnect and see if you have the same problem. If one of the sensors is malfunctioning it could tell the engine to shut down or reduce RPM. If the engine is misfiring exactly when you trim the motor it kinda sounds like either the stator or powerpack is not giving out enough voltage to power your spark and the trim motor at the same time...possibly your culprit. Good luck

Re: 1996 Ocean Pro fades away when hot

Thanks for this.Telltale has a good steady stream when idling but it can look a bit ragged at speed; I'm not sure if it's reduced or just being disturbed by airflow. I don't think she is drawing in air due to turbulence around prop but hard to tell. I'll try the temp sensors one at a time. I've been told that the mulitipin connectore between stator and coils can give problems so I'll pull them apart and clean up etc. The battery is new so I'm surprised if using the trim causes a significant volt drop but I'll certainly test stator output and then move to powerpack. Are the tests outlined on the web anywhere? and why champion? I thought equivalents were just that. Michael.

Re: 1996 Ocean Pro fades away when hot

Telltale sounds fine, it is just spraying out at a higher pressure at speed. Try using the search function here for instructions on testing the stator and powerpack. You need a PRV peak reading voltage meter to test the power pack but you can test resistance on the stator with a multimeter. If you don't have a repair manual it would be great to get one. Even though the NGKs are "equivalent" they are sometimes slightly longer than the champions that your engine was designed for. They also may not be the supression type that your motor probably requires.