Engine Sporadic After Cleaning And Adjusting Carb On 48hp SPL Evinrude

I just cleaned out my carbs with Seafoam because the idle was always rough and it had not been done in some time. Everything was good to go until I was adjusting my carbs adjustment screw to see if I could improve the idle. When using ears at home I got the idle perfect but on water testing did not go so well because as soon as you hit the gas it was instant "studdering" and it would not accelerate. On water adjustments were going pretty good... got it just right so it idled good and when I hit the gas she shot up on plane...YIPPEEEE... ..... THEN if I stopped the engine and tried it again... it would studder again for a minute or two... then blam... full power again. If I turned off and on .. same thing... every time. When I put the cover back on the engine it also had an effect on the acceleration etc. It ran better top off than on every time. <br /><br />Can anyone help...<br /><br />It's got new plugs<br />Compression is 131 cyl 2<br />Compression 135 cyl 1<br />New gear lube<br />Fresh Carb Cleaning<br /><br />What would make it so sporadic? I'm thinking something is wrong with the air/fuel mix with the carbs but it's totally incosistent.<br /><br />Any help would be GREATLY APPRECIATED

Re: Engine Sporadic After Cleaning And Adjusting Carb On 48hp SPL Evinrude

"If it ain't broke don't fix it" with that said I would hope you kept track of which adjustments you made and you should return them to their original settings. Beyond that Mr. JReeves has a great post on carb adjustments.<br /><br />Mike

Re: Engine Sporadic After Cleaning And Adjusting Carb On 48hp SPL Evinrude

You may have an exhaust leak under the cowl with the result being the engine is not getting enough fresh air. It is sucking exhaust gas.<br /><br />What exactly did you do to clean the carb?

Re: Engine Sporadic After Cleaning And Adjusting Carb On 48hp SPL Evinrude

All I did to clean carb was open up front airbox to expose carbs... spray seafoam at fast idle till can was gone and dat's it. Changed spark plugs right after that too which made firing easier/better. That was it I'll check to see if I can find an exaust problem. Thanks guys.

Re: Engine Sporadic After Cleaning And Adjusting Carb On 48hp SPL Evinrude

Hi, As you said earlier everything was good to go until adjusting the carbs adjustment screw, so its got to be a fuel/air mix problem/solution, I'm not familiar with your motor so I'm not sure if this post will apply, but this link may provide starting point.<br /><br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=28;t=036900#000004 <br /><br />Good luck,<br />Mike

Re: Engine Sporadic After Cleaning And Adjusting Carb On 48hp SPL Evinrude

Just spraying sea foam into carb. throats only does a decarb job on engine. It does nothing to clean carbs.<br /><br />You will have to take carbs apart and soak with carb cleaner. And be sure to remove welch plug in order to clean under them also. Use compressed air to clear all passages. <br /><br />Put in new needle and seats and check floats for proper setting.<br /><br />Check all fuel connections from tank to carbs for air leaks.<br /><br />Good Luck!