Need Your Opinion Don

[TexasCub]

Yesterday I got a chance to really acquaint myself with this 250 XS and I have a couple questions. The boat is a 21 ft Pro Craft Super Pro 210 and I realized that I am only able to achieve 5100 to 5200 (really trimmed out) RPMS with the motor at WOT, water pressure was in the 30 psi range. The prop shaft is 2 3/4 below pad and she has the Pro Craft 10" jackplate on her. My WOT top end speed was 62 mph (GPS). Some thing does not seem right, this boat should be running high 60's to low 70's with a tournament load according to all reports on this set up. I am only running a 25 Solas Scorpion prop so I am pretty sure its not over propped. Any ideas?

[EuropeanAM]

What's the engine's serial number????

Regardless of serial number, it's always best to START by checking some basics: (order changed based on complaint):

-Spark Test (including verification of correct, good condition spark plugs)
-Verify throttle actually REACHING WOT Position at throttle plate
-Compression Test
-Air/Fuel Pressure & Leakdown Tests
-Fuel Quality and Delivery Tests

[TexasCub]

Thanks Don, will report back. I will be replacing the spark plugs, and fuel filter today and then give it another run and see if it made any difference. She ran great and started easier than any motor I have ever ran. And I'll tell you what suprised me the most, the fuel mileage! It was unreal that I ran as far as I did and used as little fuel as I did even with this big old boat. I would easily say that it was much more efficient than my VMAX 150 Carb'd was on my 18.5 ft boat! Oh and how weird it is to have a motor that doesnt smoke!

[TexasCub]

Would a loose coil wire cause the drop in normal RPMS? I just got done replacing the plugs and found that the wire to the coil that is on the plug I pulled the other day to look at the part # was not on there tight . The little click sound that the wire makes when you pop it on a plug happened only after I pressed on it. That would make sense I guess, she turned close to 6,000 RPMS a couple weeks ago when I lake tested it to buy it.

[EuropeanAM]

Yes, an improperly connected spark lead could indeed account for a loss of power, as it might prevent proper firing of the spark plug.