Question for Mr. Weed

[Bama.Bassmaster]

Don,

I was pointed in your direction for a question I posted on the Asto/Procraft forum and so hopefully you can help me out:

I just got a '98 Astro 2000 w/ a '98 Merc 200EFI. When I first got the boat I was able to top out right at 65mph(gps), but now even with a similar load, I am barely able to make it up to 60mph(gps) at 5500rpms. I was hoping to get some help / ideas in two ways. The first would be this: any ideas on how I'm losing speed (5-7mph)? And second, is anyone familiar with the 'best' setup in terms of jackplate / prop combo to get the most from these boats?

Any help would be appreciated,

Ben

[John Jackson]

A 6" to 8" plate works really well on that boat. Both a 25" Trophy and 25" high 5 sive similar top speed performance, with the H5 having better holeshot, acceleration, handling, cornering, and rough water driving. (This is one of the few combos where the H5 really works well) You will need to have either prop worked, then jack it up until you start losing water pressure in the hard turns, then come down 1/8th inch. The pad setup on the Astro will let you easily over trim. Bow will come way up, but speed won't increase, just gives a rougher ride.

[EuropeanAM]

Thanks for the input, John! Nice to have some "specifics".

I would highly recommend that this engine be checked COMPLETELY to determine if there is a "mechanical, electrical, or fuel cause" for the loss of performance.

This should include:

-Compression test
-Spark test (including spark plug inspection or replacement)
-Fuel Pressure, SUPPLY, and VOLUME tests.

Finally, I would recommend a COMPLETE Sync-n-Link be performed, paying SPECIAL attention to the TPS adjustment.

TPS adjustment must be done on a WARM engine, with the port-side CTS (Coolant Temp Sensor) UNPLUGGED.

Then, and only then, would I recommend looking into props/plates. As a "tech", I can tell you that "changing props or setup in an attempt to regain lost performance" only FURTHER COMPLICATES DIAGNOSTIC ATTEMPTS.

[Bama.Bassmaster]

Thanks for the input from the both of you. As for changing the prop/lift, it would absolutely wait until I was able to be as sure as possible that the motor was otherwise in great condition.

Thanks again,