2004 Johnsom 25 HP 4 stroke rough idle

[SplishSplash]

I have a 2004 Johnson 4 stroke 3 cylinder 25 HP outboard that dies out at idle. It runs rough anywhere below about 1100 RPM and idles at around 850 rpm
Then it may just die at idle.
It seems like it not running on all 3 cylinders, the engine shakes below 1100rpm.
It reaches max RPM no problem and runs smooth off idle.

Any ideas? Ran some seafoam through it, changed the gas, no difference.

Plugs all look the same, clean and normal.

I bought it used and have put 10 hrs on it since but the idle has been rough since i bought it. So I don't know its history. Its not got may hours on it, its like new.


thanks

 

[SplishSplash]

Re: 2004 Johnsom 25 HP 4 stroke rough idle

Well, this was a waste of time, Thanks!

 

[ROLAND BATSON]

Re: 2004 Johnsom 25 HP 4 stroke rough idle

All I can add is that I can attest to ALL this. Same problem precisely AND I am the proud new owner of this problem...as of 1 month ago. I've not been able even to locate/purchase a repair manual to simply "adjust the idle" which conveniently the Owners Manual ignores. This motor WAS tuned up by a certified technican one week before my taking ownership. I launch and expereinced this problem. Have ever since even after dumping and starting with NEW gas.

Anyone care to comment> Had the problem FIXED?

TIA

 

[clanton]

Re: 2004 Johnsom 25 HP 4 stroke rough idle

Carbuators or fuel injected?

 

[jimdd810]

Re: 2004 Johnsom 25 HP 4 stroke rough idle

if it is carberated then rebuild carbs will fix your problem