I have a Champion 203 and here recently the prop seems to catch air when I am coming out of the hole. I have the jack plate one inch above stock level and it has been like that for two years and have not changed anything. The more weight I have in the boat the worse it does it (half a tank of gas and live wells full). It seems as if there is too much weigh up front or the trim is too high. It will start out fie but right before it wants to break over it cavitates and won�t go. I get the full RPMs out of it when I run at WOT. Why would it start to do it all of a sudden??? I have checked the prop for being bent and that the trim is all the way down. It is a 2000 Champion 203, Merc 200, 25 trophy. I can�t figure it out???

You are probably loosing the cup in the prop. But Steve is the prop guru on here. Hope he has time to chime in.

A 4 bladed prop shouldn't be causing that problem. You may have a spun hub.Is it getting worse the more you use it?

Bent Prop Shaft perhaps?

I have checked the hub in gear you can not spin the prop by hand and took the prop off and it does not look like it is spinning at all. And yes the first time it did it once and now keeps doing it. It also depeneds on how hard you get on it. You can feather it and it will eventually break over.

And they shaft does not to be bent. I have not hit any thing with the prop. The blades are clean not nics or scratches or any thing.

Mark the hub and prop with a permanent marked and run it. You are not strong enough to duplicate the torque from the engine.

cajun... what kind of motor you got on that boat?

modified 2.0 150 Merc

What he said!

First you always trim down fully on takeoff...

That 200 is a bit underpowered for a 203, doesn't help any either...

If it *used* to run good and now it doesn't, what's changed? Did you stick a transducer on the hull? Anything else that could be disturbing water flow?

Props do wear out, and change over time, first suggestion is to capture Steve here and get it tuned up. That trophy (NOT 1st choice on that hull) has vent holes for exhaust, if you're cavitating, you're getting too much gas, duct tape over one at a time to see if it changes.

the hotter the water get's the farther down in the water your boat sits. so on take off props have a tendency to blow out slightly!
if your trophy is the plus, version do like pat suggested. change out the plugs, or instal a prop seal ring.

Pat is also correct that a prop can loose it's cup. water is very corrosive, and will wear out the cup lines. not a big deal to re-surface, but it has to be done correctly.

if you're in this area, bring it by and i'll take a look at it.

I have NOT changed anything in over a year. And the 200 is not really that under powered considering I have ran 73 multiple times on GPS with two guys in it. It comes out of the hole just fine before this started. I am down in Austin so I will see about getting the prop to you.

This maybe a stupid question but are you relying on the trim gauge to tell you that the motor is fully tucked? If so maybe your gauge is not reading properly.