Prop BlowOut
02-05-2008, 07:13 PM
#1
Gold Member
Prop BlowOut
I have a 1993 Velocity 26' that had a 509 SC/250 blower and a bravo1 with a 28P Hydromotive QIV prop.
When i hit plane and the boat layed down it would jump from 3k to 4200 when it hit plane. Id have to pull the htrottle back right away so the rpms would allow the prop to grab and get me going insteat of "pulling a burn out" just in the water. I did a bit of research, the new HotBoat said it had to do with a cavation plate, a couple threads said hull design and x dimention. My x is stock but drive has a nose cone.
Any and all help Appriciated.
-Mike
When i hit plane and the boat layed down it would jump from 3k to 4200 when it hit plane. Id have to pull the htrottle back right away so the rpms would allow the prop to grab and get me going insteat of "pulling a burn out" just in the water. I did a bit of research, the new HotBoat said it had to do with a cavation plate, a couple threads said hull design and x dimention. My x is stock but drive has a nose cone.
Any and all help Appriciated.
-Mike
02-05-2008, 07:23 PM
#2
Registered
Chances are your x is higher then stock. For modern boats to perform most have elevated x's from the factory. Any way many boats do what you are describing. It is ventilating and should go away moments after the boat levels out. I don't think the cavitation plate has much to do with it at that point. If it was slipping before the bow falls thats a completely different situation.
02-05-2008, 07:29 PM
#3
Mobile Its right when the boat lays down it doesnt go away though its stays up until i brink it down. The boat will stay on plan around 28 and up, Bu i feel like im loosin tons of speed if the prop is slipping that much. I ran a best of 81.7 with the 650hp 509c.i.. Now i have a 572 short deck with 10-71 blower producing 900 h.p. Im going to use a 34p bravo1 labbed. Im hoping to run a 6k top end.
02-05-2008, 07:50 PM
#4
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Location: Virginia
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Sick, make sure you start with a stock prop to get a good baseline. I like the bravo1s but had heard some people picking up speed with the hydromotives so I tried one that was two pitched sizes larger but had been labbed, couldn't get it to stop blowing out and actually lost speed. I don't think it was the prop, I think it was the lab job.
02-05-2008, 08:32 PM
#5
My hydro blew out like crazy i mean to the point in a 2ft. chop id loose pland and could not get back on it. It would blow out that easy. I need a prop/or fix that even in a chop i can throttle up and get back on top of the waves instead od puttering in like a 23 ft. bayliner in a ripple chop.
-Mike
-Mike
