Outboard motor bogging down

[Double]

70 HP Johnson motor.  Older model, but low hours on it.  Starts up fine, but when I go to give it gas the engine bogs down and won't come anywhere near running as fast as it should.  Anyone have any thoughts on the cause?  Wondering if maybe the carbs need to be cleaned.  If so, anyone know how much of a job that is?

 

Thank you in advance for any feedback.

[Mike89]

seafoam and new high octane gas

[delcecchi]

Fuel pump?  What happens if you pump the bulb while it bogs?

[RebelSS]

 

 

 

 

[bobbymalone]

I'd put my money on a carb, but mine did that when one of my coils died.  Couldn't really notice it was running on 2 out of 3 cylinders at idle but it bogged down as soon as I gave it some gas.  Might be worth checking for spark on all cylinders before you start tearing apart carbs.  That's easy.

 

Might also be worth checking to see if you can isolate the issue to specific cylinder before you start tearing apart carbs that don't need tearing apart.