DF250 power loss - rev limiter?

[alaskaboat]

I have a DF250 with 280 hours . Recently purchased, I've run it twice this far with no issues .Went out today and can't get over 12mph before the gauge says it's maxed out on rpm. Based on running it before, as well as having run another 250 a number of times, it seems like it's nowhere near max throttle. It just doesn't sound like it's running very high rpm. But once it gets over 6k on the gauge, it starts bucking a bit and doesn't want to go higher. We ran out a few miles at this speed, but it's just not moving much . Not even enough to get us on plane, which for a 22' sea sport usually happens around 4000 rpm. It seems like what the motor is doing is very different than what the gauge is reading. Any thoughts? Thanks in advance .

[Moonlighter]

Sounds like the prop hub has let go.

Do you hear the engine revving high to match with what the tacho says?

A prop hub that has let go will usually grip at idle revs but as soon as the revs and load increase when you try to put the boat on the plane, it loses grip and the engine revs up. The engines have a rev limiter which cuts in at about 6400 or thereabouts which makes it miss and run badly.

if thats what is happening its time to get the prop hub replaced by a prop shop. You can also check if this is happening by making a across the hub centre onto the prop then take if for a test and see if the mark has moved.

[tsturm]

I have a DF250 with 280 hours . Recently purchased, I've run it twice this far with no issues .Went out today and can't get over 12mph before the gauge says it's maxed out on rpm. Based on running it before, as well as having run another 250 a number of times, it seems like it's nowhere near max throttle. It just doesn't sound like it's running very high rpm. But once it gets over 6k on the gauge, it starts bucking a bit and doesn't want to go higher. We ran out a few miles at this speed, but it's just not moving much . Not even enough to get us on plane, which for a 22' sea sport usually happens around 4000 rpm. It seems like what the motor is doing is very different than what the gauge is reading. Any thoughts? Thanks in advance .

Spun prop hub X 2. Good luck finding someone here in Alaska to replace the hub. By the time you ship it to the other 48 & back a new prop is cheaper.

[alaskaboat]

So I'm certainly conviccon it's the hub, but will double check by marking it. Thanks for the feedback. I'm thinking of going to a flo torq type prop so I can change those out in the future if needed. I can't tell if those are an entire prop though, or just a hub that you install in any type of prop. Thoughts?

[Moonlighter]

Suzuki released a new range of props a couple years ago called Watergrip that have the removable hub system., they are now the standard.

You could get one of them in the same size as your current prop. Prop and hub as a set.