Evinrude 115 Intruder

[Jabo]

Can someone please help me? I have a 1997 Evinrude V4 115 Intruder. My motor would turn 5600 to 5800 rpms and run around 55 mph. Now it turns 5300 to 5500 rpms and will not get over 50 mph and with throttle wide open you can hear the motor sound like it is bogging in and out. If you drop down to 4500 rpms and about 45 mph the motor sounds fine. It also idles fine and comes out of the hole fine. I have checked for loose connections and fuel problems, but have found nothing that I can tell to be wrong. I ran a can of tuner through it, but it did not help. Any advice would be greatly appreciated! Thanks in advance!

[RUSTY63]

Welcome to the BBC.

This may be due to the heat and humidity.

Have you checked the compression?

[Jabo]

I have not checked the compression yet, but I have a buddy that has the tools to do this so I will be sure to check it. Thanks Rusty63. I will be sure to let you know how it comes out.

[Jabo]

Hey, Rusty 63 I wanted too let you know that I Changed the spark plugs and the motor ran great for about 1/2 a mile and then it dropped in rpms and mph like it was doing before I changed them. I checked the compression and three of the cylinders read 145 and one read 130. Could this be my problem?

Thanks,

Jabo

[RUSTY63]

I would have the 130 cylinder checked.