do all big outboards running on muffs sound pretty rough

[03232001]

I have an old johnson 225 on my boat (1986) but it still runs and I've never done anything to it. When I run it on muffs she's always a bear to start up at first and always has been in the 20yrs I've owned her. Even after the 20 or so stalls i go through before i get her to idle she has always sounded poppy and with a lot of missing. But when i have it in the water It runs good so i always chalked it up to just being old,carbon fouled,and outta tune. Today I went to look at a new boat and it has a 1999 200 johnson on it that just got done having several new things installed from a qualified service marina. he hooked it up to the muffs and fired it up for me and although it fired up with out all the fuss my old girl gives me while running it sounded the same varied RPM's and missing. Do they all run kinda rough sounding? Thanks for any advice

 

[rockyrude]

Re: do all big outboards running on muffs sound pretty rough

Most motors need the back pressure being in the water provides to run correctly. If you haven't done it, do a decarb on your motor and see if it doesn't start better.

 

[86 century]

Re: do all big outboards running on muffs sound pretty rough

Every out board I have ran on muffs doesn't sound right.
From a 25hp to 250hp all sound like they are running on half the cylinders.

My parents 48spl surges bad on the muff once in the water she is so smooth you can't tell its running.

 

[rangerdave4]

Re: do all big outboards running on muffs sound pretty rough

My 91 225 sounds just like that ! put it in the water .... smooth as glass

 

[Expidia]

Re: do all big outboards running on muffs sound pretty rough

All 3 of my Merc outboards on muffs run rough, loud and twitch. But once in the water . . . smooth as a baby's behind

 

[phillnjack2]

Re: do all big outboards running on muffs sound pretty rough

some do sound pretty rough on the muffs.
recently i almost fell out with a friend over this, he kept telling me his engine sounds bad and i kept telling him its ok it
will run better in a drum or in the river etc.

and do a decarb with a simple tin of powertune or deep creep, seafoam etc, that stuff does work and can make an
old dirty engine spring back into life like you wouldnt dream.

i had a 5 year old 60 merc that i thought was running very very well and seemed strong,when i first got told about the power tune i thought just another gimmic.
when i used it i swear it gave me back a good 10% of power,much better starting,cleaner running,better fuel consumption.
so just give it a go, you have nothing to lose but loads to gain.


phill