Boat runs great early but later in the day it bogs down. Won't get on plane or over 3500 rpms. If you have somebody crawl up front it will get on plane but still runs w less power. Sometimes when you finally get it on plane you will feel a kick and it will go to full power. Motor was rebuilt last year and this was s problem before that. Some days it's not an issue. Others it's every time you take off. Boat runs great when it's running good. Any ideas would be appreciated.

Sounds like an electrical issue.

Where should I start? Strange thing is it only happens sometimes and almost always at end of a day trip.

96 Johnson 130hp Earlier this year I had the same symptoms you are describing and it ended up being an ignition coil going out.

Cool I ha be snplace to start. Thanks

Changed out all 6 ignition coils. Still having same problem? Any ideas on where to go next

You need to test all of the ignition components. http://www.cdielectronics.com/wp-content/uploads/2013/01/113-4037.pdf

Changed power pack and fuel filter. Any other ideas?

This may be a wild shot, but it's a cheap thing to check, and will at least rule out fuel delivery as the issue. What if the problem is the BOAT, and not the rebuilt engine that had the same issue before the rebuild? How could that be, you ask? What if the fuel tank isn't venting properly - such that by the end of the day the engine can't "suck" enough fuel from the tank? As you burn fuel, the tank collapses due to fuel drawn out, but air is slow to leak back in. This could add up by the end of a day depending on how much you run, etc.

Connect an external tank to your engine when it exhibits the problem and test drive. If the problem suddenly disappears, maybe the issue is the boat's fuel system. I once had a fuel selector valve that had malfunctioned, restricting the flow, and therefore the power.

That was suggested by a friend. He said to just open the gas cap and see if pressure is relieved when I do. Whould be my luck though. Put a bunch of money into it and it be that. everybody keeps saying just get a new boat but now I have to figure this out. Plus it was a great starter boat for me. I'd love to pass it on.

I've had this exact problem all summer. I've changed all coils and power packs on my 150 Rude with the same results as you discribe. The only thing that works for me is to run Seafoam in the fuel. If I don't use the Seafoam I can expect the motor to bog down on the second or third start of the day. Eventually the motor will pick up and run great till I stop and start again. When I run Seafoam the problem never happens. Maybe this will help you with your problem. Walmart has Seafoam for $7 a can.

I would change all fuel lines and clean any component that cant be replaced that they attach to.

Thanks. I'll pool it back out and keep trying different things. Been to hot to mess with

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