I purchased this boat last week knowing there was something not right with the motor. We thought it was just a spun hub so I went and got the hub replaced today but the motor is still doing the same thing. It will not get on plane. When in the water and the boat in forward the RPM will not get above 2,700. When putting the motor on ear muffs and in gear the motor will get up like it should. I know in the water its under pressure and that has something to do with it but I'm lost as to what to do to fix it. Thank you for the help. Video in comments.

Motor is a 2000 Evinrude 225
Boat Stratos

Knowing what make/model boat, hp of motor, and prop make and pitch would be much more useful. Also reving your motor out of the water will make inside parts outside parts in the blink of an eye.

27 is a really big wheel for a 225. Now the advice about to be given might not be what you want to hear. But..

Find a 24 raker, 25 tempest with a OMC hub, anything smaller that is a known good prop, and run it. If you get what you want then it's just prop. If it doesn't don't run it again until you get the motor checked out thoroughly. That motor is suspect for going lean on a cylinder, which turns it into a grenade really quick.

Way too much prop

The motor was checked out before buying the boat. Everything besides this seemed to check out. Compression was good on all cylinders so hopefully its just the prop. I was thinking the prop looked awfully big but wasn't sure.

Pay attention - this man's advice is probably the most informed you can get on the TFF for such matters. As mentioned, don't rev any motor up high on the muffs. That didn't tell you one darn thing. That's like getting in your truck that accelerates sluggish, then revving it in neutral and concluding the engine is fine. Of course it will do 5000 RPM with NO LOAD on it - it will also blow up easily - that's the "inside parts become outside parts" comment.

Thanks for the help. I checked compression I thought that would show if there was an issue with cylinders. I am looking for a prop now.

I lean towards starvation of fuel, air, or spark. 2700rpm is awfully low. I'd start with the basic fuel system checkout.
Tim

Check and examine your plugs (for spark) and coil wires...

engine is in s.l.o.w. mode speed limited overheat warning. probably a temp sensor bad or bbad power pack

So not a prop issue?

check spark at ea. plug, inline testers are cheap. https://www.napaonline.com/en/p/BK_...YbO2UzFGl50ko0xwlt24qQyMs4hoC4bwQAvD_BwE

check spark, should be strong and bright. having owned a couple of johnnyrudes it sounds like your power pack is gone, easy fix but need to diagnose it first.
had one do the exact same thing, and it was power pack gone bad.
like pat said too, prop is way too much, that engine should love a 24 raker but have it worked and trued, www.stevescustomprops.com josh can do ya a great job.

Checked all plugs with inline tester. Everything was good.