Inline6 90 to 115 hp?

[Newbee24]

Hey guys! I have a 1986 mercury 115 powerhead that burnt a piston rings. I then purchased a powerhead that claimed to be for 90hp and 115 hp. I installed the power head and took it out to try. It didn't have the top end o expected and will not rev passed 4700 rpm. The powerhead looks the same and I installed the carbs from the 115. Is there a difference with powerhead or can I use parts from the 115 to regain the hp.

 

[Chris1956]

The block of the 90HP il6 has different porting and likely different pistons than the 115HP il6. If you bought a 90HP powerhead, you have a 90HP motor.

 

[racerone]

So you installed a replacement powerhead ?---Did you determine the cause of the powerhead failure ?-----Did you inspect / trouble shoot all your old parts before installing on the rebuilt.-----Hopefully you do not cause the same issue again.