Bravo 1 vibration and intermittent slip
 

Why do I feel my driveline vibrate more the harder I turn it? Did a motor swap and it did with the old motor too, almost seems more now although i did up the power too. Does it full trim up too at like 70mph. Gimble and u joints seemed smooth by hand and took grease in August when I finally got this together. Alignment was good and checked. Coupler is unfortunately ungreasable so I have to just pack some in there.
I almost have a on plane slippage problem like once a year too. Ill be on plane playing with the stick on rougher water and then all of a sudden it revs up and doesn't grab good till i pull it back down. No slam or clunk and i go on about the season. Is it possible that the coupler or drive hub could have an intermittent slip ? It's done it once a season for 3 seasons. Or are my 2 problems related?

Summer89,

Worn cone clutch?

Thanks. Brad.

Brad, I heard if those cone clutches get worn it'll cause shifting issues. My shifting is good. And if they're worn enough to be doing that what I have going on, then they are completely cooked and I should be having more issues. But I've also heard if a couple or Hub slips once then they just keep slipping and don't really do it intermittently.

Summer89,

That was why the question mark. The hub is also a possibility, as there are really only two places slip can occur without sh!t really going sideways: cone clutch and hub. A new hub is a relatively cheap fix and pretty non-invasive to do.

Thanks. Brad.

I did just put a new prop on this season. I reused The Hub from my old one and it was the solid Flo torque one for over 400 horsepower. It seemed to go in but I wasn't struggling to put it in couple Bops with a hammer and some WD-40

The vibration and when it does it points to U joints

That was my thought too -- and just because they feel ok by hand, does not mean that they are ok under load.

Yeah there was no resistance to them. I was kinda thinking them. And adding 150+ hp and still running them didn't help. And they took a beating last weekend at the local river rumble. Luckily I have only 2 more weeks before winterization and storage. Sounds like a next year problem.

Back to the cone clutches, so they can slip intermiintermittently and not get destroyed? I have no shifting problems, a shower, and when it does it it doesn't feel like a neutral rev it still has some load but just starts to lose speed.

Prop cavitating/airation?

Cone clutches don’t slip once it’s in forward or reverse. A bad cone clutch will just have a delay when shifting it into gear. You slip issue sounds like the prop is cavitating

Sounds like the OP just ends up getting the prop in the sweet spot once in a while and blows out the prop. I can't imagine a small diameter clutch system would take that level of heat/tq slip and not be having issues slipping all the time with that level of HP.

It’s possible. I have Been there, done that.

[QUOTE=SB;4936294]It’s possible. I have Been there, done that.[/QU

That happened to me once too on my 25' single engine. It was the oddest thing, we stopped in the middle of the river to meet up with others and when I went to get back on plane it felt like something was slipping. It happened several times. A buddy suggested the rubber prop hub was bad. We got to the marina we were staying at and I pulled the prop to look at it. It's a solid hub, it had been so long I had forgot what was on it. Anyway after some beer and discussions at the marina that night, we chalked it up to conditions - boat load (we had packed for a 3 day weekend), wave action, and tide. It never happen again.

OP said he put new prop on this season which made me think cavitation.
What prop, new and old? Pitch,diameter, blades, brand?
Bibration would be my main worry. Sure sounds like u/joints.

Sounds like a prop hub to me.