Merc. 115 4-stk. Bad High Speed Performance

[PHILLY9]

Could Someone Tell Me Some Of The Basic Problems To Look For On My 2002 Merc. 115 4 Stroke. It Starts Good And Runs Good At Low And Moderate Speeds, But Will Not Go Over 3800 To 4000 Rpm. Some Of The Things I Have Already Done Are: New Plugs And Gas Filter,fresh Fuel,had The Throttle Adjusted And The Prop Checked. It Used To Go About 43 Mph And Now Will Only Reach About 30 Mph. Help!!!!

 

[Dreddrs25]

Re: Merc. 115 4-stk. Bad High Speed Performance

Sounds to me like a fuel issue. My Merc would start up and run smooth until about 12-15mph, then fell on its face. I found that my fuel lines had some kind of restriction. Messed with the pressure and got it running like a champ.

Check for blockage at the filter and be sure your fuel line has enough pressure. GL

 

[PHILLY9]

Re: Merc. 115 4-stk. Bad High Speed Performance

Thanx. I'm Going To Make Sure The Gas Vent Isn't Clogged And Then Try Using A Portable Fuel Tank. But I Have A Feeling That It Is Something Else. Philly

 

[andy6374]

Re: Merc. 115 4-stk. Bad High Speed Performance

Have you checked compression or verified that there is spark on all the cylinders?

 

[PHILLY9]

Re: Merc. 115 4-stk. Bad High Speed Performance

No I Have Not. I Don't Have The Tools To Check Comprssion And I Will Check Spark Later Today. Thanx