09 mercury 60hp 4stroke running rough at low rpm.

[joeblow31129]

I have an 09 60hp 4stroke bigfoot and it has problems running at low rpm. It runs fine at idle and at high rpm but when it runs around the 1300-1800 rpm range it runs rough,stutters like it has a miss. Has anyone else had this problem or knows what causes it??

 

[Maxz695]

Re: 09 mercury 60hp 4stroke running rough at low rpm.

At idol it would seem to be water intrusion which is not your case. your description points toward fuel or an electrical issue being A a restricted fuel situation. B The timing is off, C The stator could be affected and D coils, wires grounds plugs etc , It also could be bad carb adjustments. Dose the engine take off when throttling up or is it sluggish? What is the volts saying in the batt gage? Believe it or not the rectifier and regulator have alot to do with proper firing and engine performance

 

[Fleetwin]

Re: 09 mercury 60hp 4stroke running rough at low rpm.

I have a 2012 version of that engine. Mine is EFI, I assume yours is too?

Mine has a spot around 1500 that it does not like. Not bad, just noticeably rougher.

Is it possible your experiencing some cavitation at that speed?

Are you seeing the tach. needle jump?

 

[joeblow31129]

Re: 09 mercury 60hp 4stroke running rough at low rpm.

Its an efi so not a carb problem.(should have said that sorry) its been into the mechanic but they couldnt get it to run rough in the test tank so hard to fault find unless on the water i guess (still charged $$$$$ so cant afford to continually put it in the shop). I will check out the voltage when i get home from work tomorrow and see if thats the problem. I would have thought being if its a fuel problem it would still run rough at high rpm also, not just at trolling speed. The problem that it has seems to make the motor miss badly when trolling. I only noticed it after the 100hr service was done but the dealer went bust so i cant talk to them about it.

Keep the ideas coming if you can please because im stuffed if i know whatelse to look at.

 

[Fat Freddy]

Re: 09 mercury 60hp 4stroke running rough at low rpm.

Its an efi so not a carb problem.(should have said that sorry) its been into the mechanic but they couldnt get it to run rough in the test tank so hard to fault find unless on the water i guess (still charged $$$$$ so cant afford to continually put it in the shop). I will check out the voltage when i get home from work tomorrow and see if thats the problem. I would have thought being if its a fuel problem it would still run rough at high rpm also, not just at trolling speed. The problem that it has seems to make the motor miss badly when trolling. I only noticed it after the 100hr service was done but the dealer went bust so i cant talk to them about it.

Keep the ideas coming if you can please because im stuffed if i know whatelse to look at.

I have the same issue what was your problem?

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