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showstoppercat
12-18-2007, 07:32 AM
Running SV with octura x440 - cavitates how do I fix this problem???

Fluid
12-18-2007, 06:27 PM
There could be several problems, depending on how severe the cavitation is. Does the boat move, or does it just sit there? A small amount of cavitation is normal. If the prop is not sharpened it might cavitate some. If the strut is set too shallow it can cavitate. Too, a small prop will cavitate more, you may be using a prop too small in diameter for the boat/setup.


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domwilson
12-18-2007, 06:33 PM
Buy a Blackjack....Just kidding.
Is the prop sharpened and balanced?
How are your batteries placed?

mike martin
12-18-2007, 09:59 PM
try a x645 prop i think the x440 is to small

H&MWill
12-19-2007, 12:13 AM
I agree. We run X645's and they only cavitate for a sec. Also try a Grim 42x55 2 blade or 40x52 3 blade. Both very nice.

showstoppercat
12-19-2007, 12:22 AM
Supervee27 is straight of box - the first run all i changed was prop to x440 haven't touch anything at all - Batteries connected and fix to appropriate battery spaces - I gave it full throttle for 10-20secs and motors sounds like running fine but SV moves very slowly - No blistering speed at all - this prop was recommended by Twisted Liquid and Grimacer - I do have cf45's and 48props but I got frustrated and went home ...
please help i was looking forward to getting this boat

domwilson
12-19-2007, 12:50 AM
Try the CF45. Alot of people use that or the X642 with great success.

Bill-SOCAL
12-19-2007, 12:54 AM
Try putting the power in smoothly rather than just nailing the throttle.

I run a GrimRacer 42x55 prop (S&B) and I get very little cavitation. Only takes a few seconds to get moving. But if I just nail it to WOT then the prop digs in and it takes longer to get moving.

Joe Friars
12-27-2007, 12:55 AM
My stock prop broke on the first run. I got an x440 and a x640 per the manual and what was available in my local hobby shop I s&b the x440 the best I could (I,m new at this.) and it runs pretty well. yeah it cavatates for a bit but it always gets up on plane and flies. I just don't gun it until it gets moving a bit.
Joe

Mich. Maniac
12-27-2007, 10:04 PM
Buy a Blackjack....Just kidding.
Is the prop sharpened and balanced?
How are your batteries placed?
:laugh: :laugh: :laugh: :laugh:

mr.mauian
12-28-2007, 07:08 PM
x442 prop is what we run here in Hawaii and no cavitation at all. I beleive there's some vids of us somewhere here. you must check your cg too, batts to far back will only cause more cavitation and when it finally gets on plane hop like a rabbit.:w00t:

showstoppercat
12-29-2007, 04:34 AM
cavitation problems fix - need to coreect batt position as you say is hopping like a rabbit on a hot tin roof - how far forward should???? i go i have tried one cell forward and sv runs alot better - but want to go to far as i dont want to loss speed

Bill-SOCAL
12-29-2007, 10:38 AM
Just experiment. You are not going to hurt anything. I balanced my SV at 7.75 inches from the transom. With 6-cell NiMH packs they were about 3 cells forward of the stock location.

C-MURDER
07-20-2008, 08:58 PM
Hey there,

Was wondering if anyone could give me a bit of advice. I have three problems,

1. At first it was serious cavitation and not even able to get on plane. Then I adjusted the batteries and moved them forward. the boat hops despite moving the cell forward almost 3 inches (It hops less, then straight out of the box, but it still hops.) whats the best thing to correct.. tab angle, prop shaft angle??.

2. How on earth do you change the propshaft angle?? I took it apart and the stuffing tube extends enough that there's no way to change the angle without bending the stuffing tube down also.. doesn't seem right.

3. EVerything gets HOT HOT HOT. the motor gets so hot I can't touch it. I brought it around a few times and did see water exiting the water cooling outlet..so that is working, but do I need more cooling? The batteries also got ridiculously hot. I"m running some good quality 3600 mah packs.

Thanks

Apples1
07-21-2008, 04:56 AM
sounds like something is binding and putting extra load on everything to get that hot.