Prop torque and boat lean

[seahorse whisperer]

Hello all

I previously posted about some significant issues with my new boat (leaks, lean etc). All of the problems seem to be sorted, although the lean is still an issue.

When under way, the boat tips to port as soon as the boat starts to plane. While the lean is now not as significant, due to manufacturer "re-jigging", it is still there and I am not prepared to accept anything other than a perfect rig. If this had been the only issue with the boat, I would perhaps be a less insistent.

After testing with the manufacturer and the dealer, they agreed there was a problem (the manufacturer grudgingly). When we took the boat out of the water, I asked them if they had adjusted the height of the motor during the last effort at repair. They hadn't.....

Looking at the motor on the ramp, the cavitation plate on the motor was significantly (about 60 mm) below the keel of the boat. My understanding is that this would greatly enhance the effect of prop torque and that the cavitation plate should be level with the keel, or slightly above. Am I correct that this should reduce prop torque and the boat lean?

I have asked the dealer to change the motor height and re-test the boat. I hope this is a simple solution!

[Noelm]

not too sure the Motor height will have a huge bearing on prop torque, but you never know, can't hurt to give it a try! is there any chance of a test run (setup by the dealer) in another Boat the same as yours?? this will determine if there is a problem with yours or all of them!

[seahorse whisperer]

Unfortunately, I doubt it. Regardless, this boat has spent nearly as much time in the workshop as it has at home, so I am not really in the mood for more tests etc. I hope the motor change fixes the problem. I don't need it perfect, but I do need it a lot more perfect than it is.

[Noelm]

if it is a new outfit, then I would want it to be dam near perfect! other wise you might as well buy second hand if you have to tolerate problems!

[fishing111]

if it is a new outfit, then I would want it to be dam near perfect! other wise you might as well buy second hand if you have to tolerate problems!

Ditto to what Noel said!
You bought a new product didn't you?
Why settle for even close enough, settle for how it should bloody be.
Hope you get it sorted.

[seahorse whisperer]

Thanks guys. Sure it will sort out eventually. I'll just keep harassing the dealer (they are OK) and the manufacturer until I am satisfied. If the motor change corrects the problem and does not cause cavitation, I will be very happy.

[BaitThrower]

I had to raise my little 5HP up about 3 inches so cav plate was close to level with keel etc. Although I had no major problems before with it lower, once I raised it up she performed much better (less leg in water and hence less drag). Just gotta be a bit more careful in heavier chop or turns as the prop can break the water surface and cavitate. But yeah I'd look at raising it a little anyway for better performance, particularly when on the plane. This is what all the boating reference books say anyway. :)

[ozbee]

are we talking about deep v or what

[seahorse whisperer]

Deep vee aluminium with Maxi Transom.

[seahorse whisperer]

:-/ Millenium Hull......