Crest 27' w/ DF140hp Suzuki Rev limiter issues

I am new to this site and am looking for some insight. I have a 2006 Crest Savannah LSTX with a Suzuki DF140hp motor. The boat has always seemed slow and the speedometer does not work but as we hardly use it i never really checked it out. Sat night we were 12 miles from my marina running at 5800 rpm and moving at 18.4mph per my gps.The rev limiter kicked in and freaked us out. I let it sit for about 5 min to check things out. Once up to speed it happened again. I slowed to 3500rpm and it happened again. I limped home the final 4 miles at 8mph!

Thoughtst? How fast should this boat run at wot? I am uncertain what the prop size is but it is original. The motor is still under warranty.

Thanks.

Re: Crest 27' w/ DF140hp Suzuki Rev limiter issues

The Overspeed warning should not have come on at any of the speeds you were running so I suspect there is a wiring or ECU gremlin that your dealer should have a look at since it's under warranty. As for speed, I am guessing but 30 MPH is certainly in the ballpark. Since you are getting only 18 MPH at 5800 RPM, something is seriously wrong with this setup. Spun prop hub perhaps. My 18 foot Misty Harbor goes faster than that with a 40 HP Suzy.

Re: Crest 27' w/ DF140hp Suzuki Rev limiter issues

Yeah something is wrong there. 27' is a lot of boat to push so depending on how many people, how much gas and overall setup of the Deck Speed can change. If you have 3 logs and a couple Adults on board I would say WOT should get you 28 - 32mph. 2 logs 25 - 28mph. 18mph should be around 4500 rpm. Again I am guessing here because every toon seems to be different.