Boat running sluggish

rktktpaul

Recruit
Joined
May 7, 2008
Messages
5
As stated below, 4.3l V-6, 2bbl carb, Alpha 1 Gen 2 outdrive. I've run the boat the past 2 seasons with the 23 pitch prop the boat came with. With that setup, I have run about 45MPH (GPS) @ 4400RPM WOT. Mercruiser states that the WOT range for my setup should be 4400 - 4800 RPM.

Upon the advice of a Sea Ray dealer and the guy who fixes my prop, I bought and put on a 21 pitch prop before this season. This should have gotten me closer to 4600 RPM, which would be midrange of WOT.

The boat just didn't feel right with this prop; it felt like something was holding the boat back. Wide open, my numbers actually dropped - 37 MPH (GPS) @ 3900 RPM. Thinking it was a bad prop, I put my 23 pitch back; things did not get better, and the feel of dragging something heavy behind remains. So obviously there is an issue engine wise.

The only thing that is different from last year was during the last run back in October, I hit something underwater that took a few hunks out of my prop. I ran back to the ramp at low speed because I was getting some pretty good vibrations from the prop. The other issue is some electrical gremlins that surfaced this year; you can read about that in this link:

http://www.clubsearay.com/forum/showthread.php?t=12066

Anyone have any ideas what I should look at or for??
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,072
Re: Boat running sluggish

Check fuel system.Water seperator/fuel filter/filter at carb/pickup in the tank.Linkage??? Putting on electronics shouldn't bother top end unless you hook them to the coil.Try disconecting your tach when running see if it changes anything.Jerry
 

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: Boat running sluggish

Could the engine and drive be out out alignment from that hit you took and binding the shaft?
 

rktktpaul

Recruit
Joined
May 7, 2008
Messages
5
Re: Boat running sluggish

Had the alignment checked when I brought the boat in for winterizing last year Chiefalen; thanks for the thought though!

Jerry, I'll try your suggestions. For some reason I have the feeling that this problem is related to the electrical system.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,072
Re: Boat running sluggish

This is the first thing I should have said:do a compression test.I had a friend who had the similar problem and it turned out the fuel line had degraded and was blocking the line.J
 
Top