Can't get to full speed

[Steel84]

I have a 170 aq volvo penta with the three carb setup on in and can't seem to get to full rpm's even when I am under full throttle. My gauge is reading 3000 rpms even though I should be close to 4000. The gps reads 17 mph when I should be going at least 30 mph. The carbs are pumping gas and the boat ran fine up until now. The outdrive is a 250 and the whole setup us from 1971. Can anybody help me please????
Pat

1971 20' Thompson Fisherman
Volvo Penta 170aq/250 Outdrive

 

[airdvr1227]

Re: Can't get to full speed

Anything growing on the bottom of your hull?

 

[LAC_STS]

Re: Can't get to full speed

As they told me...


http://forums.iboats.com/showthread.php?t=295070