[SparkieBoat]

I have a 95' 150 Intruder Evinrude GL model, on a 17.5 Mckee Craft. I can only spin a 19 pitch prop about 4250 RPMs at about 34 MPH. I ran some checks on what I should expect at this website.
http://go-fast.com/boat_speed_predictions.htm
I weighed the boat today, it is 3060 LBS including the trailer, motor, anchor,2 batteries, CC, and 15 Gallons of fuel and maybe about 40 lbs of misc stuff. I figure the trailer weighs around 500 lbs. I ran a check on this web site at 3000 lbs. with a 250 constant at 50 mph and it came up with 120 HP motor. Well my actual weight is probably closer to 2800 lbs fully loaded and I got a 150 HP. I fully expected to bust 50 MPH wide open. I expected to be purchasing a 21 or 23 pitch prop for the motor. I have checked compression, spark, cleaned carbs, new fuel pump, new intake manifold gaskets, new thermostats, I ahve been through this motor thoroughly and I can not figure out why it is not pushing better. with the intake butterflies about 1/2 open it is running about 4100 rpms and ab out 32 mph as I open it on up it begins to power up then just when I open it up all the way it acts like its getting ready to increase power for about a split second then just "bogs out" and settles in back at around 4100 RPMs, as I begin to throttle up if I stop just before wide open I can get it to around 4250 RPMs and 34 MPH. any ideas on what to check/test would be appreciated.

[steelespike]

You should put this in the Evinrude section.
Speaking generically it sounds like a fuel delivery problem.
A carb rebuild may be in order with special attention to all passages and jets.Check the fuel pump.You might try squeezing the primer bulb if it helps that would indicate weak fuel pump.You might pull the plugs and look at their condition.Especially color.

[jonesg]

Yeh check fuel delivery, compression and spark with a gap tester.

Then check timing pickup roller for correct position.
http://bbcboards.zeroforum.com/zerot...ment-60-motors

[SparkieBoat]

roger that Jones already done each thing you suggested...brand new fuel pump and it seems to be working well..I also had a low pressure (3-5 psi) electric pump connected at the tank and it made no difference. thanks for the input