Prop Help for Wakeboarding....

[AaronWhitt82]

Hey guys I have a '99 Moomba Outback with an Indmar 5.7 litre, 310HP, Carbed. The boat currently has an O.J. 3 blade 13X13 prop.
I want a different size prop for more low end/torque and pulling a skier/wakeboarder out of the hole. For some reason it doesn't seem like this size prop is doing it well enough. I want a prop that will have a good holeshot, but not totally lose the top end. I don't mind if I lose a few hundred RPM's though. If someone could please recommend some other sizes I'd appreciate it alot!
Thanks,
Aaron

 

[HighTrim]

Re: Prop Help for Wakeboarding....

You should probably get a separate prop for wakeboarding alone. Loosing WOT rpms is not good for the motor in the long haul. They make specialty props just for what you need

 

[Bondo]

Re: Prop Help for Wakeboarding....

I want a prop that will have a good holeshot, but not totally lose the top end. I don't mind if I lose a few hundred RPM's though.

Ayuh,......... You've got it abit Backwards.......

Dropping the Pitch # will Increase the RPMs,+ probably lower the Top Speed of the boat.......

For some reason it doesn't seem like this size prop is doing it well enough.

I'm wondering if maybe you have some Other Issues going on,......
A 13"X13" Should pull like a Freight Train.................

 

[seabasser]

Re: Prop Help for Wakeboarding....

if you want more pull you need to put as much diameter on as possible, but reduce the pitch, losing rpms at wot will destroy an engine.

 

[AaronWhitt82]

Re: Prop Help for Wakeboarding....

Hey guys I appreciate the replys. I haven't been on here in a while so sorry for the delayed response.....
I've done some researching and am deciding between an Acme 3 blade 541 which is a 13X12 cup of .080 or an Acme 3 blade 543 which is 13X11.5 cup of .080
My transmission is 1:1 and with either of these props I should be in the WOT range no problem. They should also help me with the holeshot I'm looking for, but I may lose a bit of top end speed which doesn't really bother me.
Just wondering if you guys have any other tips or reccomendations?
Thanks,
Aaron

 

[JustJason]

Re: Prop Help for Wakeboarding....

is this a 19 foot boat or a 25ft boat? either way a 310 should pull a wakeboarder up no prob. as bondo said.... Make sure there's no other problems with the boat. A 310 inboard should pull like a mutha

 

[AaronWhitt82]

Re: Prop Help for Wakeboarding....

It is a 21 foot inboard boat.
I was having issues earlier in the year with the carb/fuel system, but have since got everything fixed and worked out.
I was having problems trying to pull my buddy out of the hole on a slalom ski that weighs 200 lbs. or more and it seemed like the boat was struggling a bit when I hammered the throttle down it hesitated a bit then took off, but it was unable to pull him up and out of the water and I tried a few times to get him up, but no luck. He said it almost seemed like there was a "lack of power" and seemed like the boat didn't have enough to get him up...
I am using no ballast whatsoever and had maybe 4 other people aboard.
When I'm not pulling someone behind the boat and I hammer down it takes off like a bat out of hell on holeshot and gets up to speed and RPM's no problem. It's just when pulling someone heavy it seems like it doesn't want to do it so that's why I was considering changing the prop.... Pulling someone lighter it has no problem.
Maybe I do have some other issues at hand, But I won't know until a few months because it is in storage for Winter.....
Thanks again

 

[JustJason]

Re: Prop Help for Wakeboarding....

how long have you owned the boat? was it giving you this trouble before you had carb/fuel system issues. What issues were you having?? 5 people in the boat (including you) plus pulling a skiier is starting to get up there as far as weight goes. So there may in fact be nothing wrong with the boat, just that you are loading it a bit more. It's just that the last thing you want to do is use a prop as a band aid for another problem. The boat isn't that old. I'd say your best bet is to contact Moomba tech/customer service directly. Explain to them your operating conditions, how many people you have in the boat, the weather (temperature) when you were doing this, and your prop size. Basically the more specific you are with them the better they can help you.

 

[AaronWhitt82]

Re: Prop Help for Wakeboarding....

how long have you owned the boat? was it giving you this trouble before you had carb/fuel system issues. What issues were you having?? 5 people in the boat (including you) plus pulling a skiier is starting to get up there as far as weight goes. So there may in fact be nothing wrong with the boat, just that you are loading it a bit more. It's just that the last thing you want to do is use a prop as a band aid for another problem. The boat isn't that old. I'd say your best bet is to contact Moomba tech/customer service directly. Explain to them your operating conditions, how many people you have in the boat, the weather (temperature) when you were doing this, and your prop size. Basically the more specific you are with them the better they can help you.

I bought the boat at the end of August last year.
The previous owner only used the boat maybe twice a year and when he wasn't using it the boat was stored indoors. The owner claims it was serviced at the beginning and end of each year. It had fresh oil and trans fluid in it when I picked it up, but other than that I don't know what other kind of service the dealer did. I wonder if I called them if they would release all that info to me?
I'm assuming since it sat alot that probably led to all the carb and fuel issues I had.... I replaced fuel pump, plugs, cap, rotor, fuel filter numerous times, rebuilt the carb, & fuel shut off safety switch.
I never pulled a skier with it before the problems started..... Only after I had all the problems sorted out and fixed is when I first started pulling skiers with it.
The boat is also rated for 8 people, but I forgot the max weight on the sticker.
I guess I'll have to wait until Spring and see what happens with it and maybe need to do some more tweaking on the Carb......

 

[walleyehed]

Re: Prop Help for Wakeboarding....

It "may" be rated for 8 people, but that's for flotation issues and handling saftey...doesn't mean it will perform with 5-6-7-8 on-board.
A 3-bld for wake-board may be fine, but for ripping a skier up, it may require a 4-bld on a thru-hull shaft-drive.

 

[tommays]

Re: Prop Help for Wakeboarding....

On the 351 powered Correct Craft we try to keep a MAX of 3 and a Skier a few more people really makes the motor work really hard as well as the fuel BILL



Tommays

 

[steelespike]

Re: Prop Help for Wakeboarding....

In my opinion a straight drive inboard is the best for skiing etc.
Spent my youth in and around boats.Could never get up behind the various outboards in our group.weighed 135# motors to 45hp.At about 18 I tried behind a 48 18 ft Chriscraft with a 95 hp flat head 6.boat weight about 2,000lbs.
I was up instantly.We used to pull 2 good skiers one a 200 pounder behind a 39 45 hp Chriscraft inboard.it was tough and not very fast but worked pretty good.My 18 ft 53 105 hp Chriscraft you could hardly tell the difference whether just me or my wife 2 kids and 2 nieces were aboard,rpm drop was something like 150.To me a 21 ft 310 hp boat should easily haul a 200 lb skier
even with 5 people.Of course if they are all sitting near the back that would be tough.My guess is there is still some sort of fuel delivery problem.
You might want to do a compressioin check and be sure shes firing on all cylinders.Try turning the prop shaft by hand in neutral you'll feel a slight drag but should turn easily.