2000 Johnson 130HP Ocean Pro problems

[CaptDuck]

Let me start by saying what the engine is and what it is on. I have a 2000 Johnson 130HP (J130VXSSS) on a 2001 Sea Pro 1900 CC. Yesterday we went out and everything was going fine. We launched the boat and ran WOT for about 20 minutes and threw the anchor to do some fishing. Sat there for about 2 hours and decided to go and do some cruising. So we started her up and took off. We ran WOT for about 1 hour when the alarm went off saying HOT. So i threw it in to neutral and the alarm went off. I turned it off to make sure nothing blocking the water pickup screens. I lowered it back down and turned it on. She was peeing like it should and i put it in gear. She started up fine and i gave her some juice. I couldn't get above 2500 RPM's with out shaking like it was going to fall apart. So i kept it at about 2000 RPM's and headed towards the dock. We stopped at another fishing spot and fished for abut 45 minutes. Time to go and she started right up. This time i was able to open her up and no alarm and no shaking above 2500 RPM's.
She has new spark plugs QL78YC gapped at .030, new prop shaft seals and new water pump. So where do i start troubleshooting at? Ignition coils? Regulator? Power Pack? Would like to fix this myself compared to taking it in. This is my first outboard always have I/O's in the past. I have ordered a service manual already as i just bought this boat. Thanks in Advance for the help!!!

 

[Chris1956]

That motor should have the SLOW system which limits RPM, when she overheats. Perhaps that is what caused your low RPM.

I would inspect your thermostats and see if they work properly. You can also test your temp sensors, one on each cylinder head.

Thermostats and overheat sensors may be tested in a pot of hot water on the stove. Hang them in the pot and warm up the water. Thermostats should open around 140*F. Overheat sensors (tan/blue wire) will close (ground to block) at 240*F. Obviously this is above the boiling point of water, so the best you can do is see that they are still open when the water boils. If so, they are likely good.

 

[CaptDuck]

Well i took the thermostats out and suspended them in water. They opened up as they were supposed to, but they wouldn't close unless i pushed the pin pack in. I also tested the temp. sensor and that was ok.