2005 Johnson 4 stroke problems

Please help! I have a 2005 Johnson 4 stroke 70 HP outboard motor that boggs down at high RPM's. It runs fine below 3000 RPM. I know by reading the manual it has a safety that engages when problems arise but is this the problem & if so how do you reset it? If you don't think this is the problem & have any suggestions I would appreciate you help! Thanks

Re: 2005 Johnson 4 stroke problems

I would buy rebuild kits and do the carbs, run wire through the jets, specially the hi-speed jet as thats the one suspected.

change fuel filter too.

Re: 2005 Johnson 4 stroke problems

jonesg said:

I would buy rebuild kits and do the carbs, run wire through the jets, specially the hi-speed jet as thats the one suspected.

change fuel filter too.

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EFI.................



The engine is limited to 3000 rpm if there is an issue. Do you have a "Systems Check" tach on yours? Low oil, low oil pressure, and Over heating will all cause it to go into "limp home" mode. It could be a bad sensor for one of those or the Neutral safety switch in the control box could be stuck/bad also limiting it to 3000 rpm. If it will go above 3000 rpm and start to bog then check the fuel filters (2 of them) and drain the Fuel Pump canister in case water got in. There is a small screw in it and its located between the intake manifold and the engine with a small clear hose attached just below the screw. You could also big the primer bulb a pump or 2 to see if it clears up the bog, if so you may have a bad transfer fuel pump.

Re: 2005 Johnson 4 stroke problems

Thanks all I believe it was an overheating problem that caused this to happen. A boater in front of me was bottoming out & stirred up a bunch of crap on the bottom & I noticed the water jet was not as strong as usual. I did try flushing the motor out & the water stream got better then slowed down again.