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Hoopskier
06-15-2009, 05:22 PM
I recently picked up a new prop for my 03 OB. I was using an OJ 13x13 4 blade (came on the boat). I picked up a new OJ 13x13 3 blade.

I really like my new 3 blade vs 4. I noticed the difference right off the trailer. When I put the boat in gear it would idle at a faster speed. On the top end is better, brought my rpms down to 4600 instead of 4900-5000 (would be on the Rev limiter).

The hole shot i didn't notice much difference or at least nothing that a little more throttle couldn't take care of.

I should clarify that i run a light boat compared to the wakeboard crowd. No ballast for me, just a full tank of gas:cool:. I'm more traditional skier/general use than wakeboard.

I'll keep my 4 blade for a spare, or if i decide to run the boat heavier.

kaneboats
06-15-2009, 05:25 PM
I wakeboard and surf using the 3 blade 13x13 OJ and it's great. I have an extra one in a box in the garage if you nick yours and want to swap for the 4blade one. I usually run a lot of people plus ballast so I wouldn't mind the 4 blade. I used to have one before my little mishap last July. The shop ordered the 3 blade b/c that's what goes on on Outback in the specs.

MOOMBA_97
06-15-2009, 06:40 PM
I just bought and installed the new OJ XMP 3 blade, 13 x 11.5 last week. I was running a 4 blade 13x 13.5 stainless steel. I can honestly say I wished I'd done it soon. Holeshot is much better and I gained some much needed top end speed. The boat even handles better. This is a great prop for anyone looking for another.

Monty

LSM
06-15-2009, 09:02 PM
I have an 06 LSV that I just bought this spring. I ran it a lot this past week and I think I'd like to try a different prop.

I'm not sure what pitch mine is but it is the factory 4 blade for an 06 LSV.

My top end is not much over 35 if any at all. The boat drinks alot of gas cruiz'n at 28 to 30 mph.

I know the boat is WB boat but right now my kids are small. What is a good prop for a 06 LSV that will lower RPM's a bit, maybe give me a little more on top end for cruiz'n and still pull small kids, and me every now and then.

Will the 3 blade you all mention do the trick for the LSV?

Hoopskier
06-16-2009, 01:39 AM
I have an 06 LSV that I just bought this spring. I ran it a lot this past week and I think I'd like to try a different prop.

I'm not sure what pitch mine is but it is the factory 4 blade for an 06 LSV.

My top end is not much over 35 if any at all. The boat drinks alot of gas cruiz'n at 28 to 30 mph.

I know the boat is WB boat but right now my kids are small. What is a good prop for a 06 LSV that will lower RPM's a bit, maybe give me a little more on top end for cruiz'n and still pull small kids, and me every now and then.

Will the 3 blade you all mention do the trick for the LSV?


The best place to start is going to be to figure out what it has for a prop now. It should say on the prop. Mine had a part number on the side. Otherwise you can remove the nut that holds the prop on and should say the size and pitch. The markings are under the nut, you don't need to remove the prop. (first number is diameter size X Second number is pitch)

From what i read about props the vdrives still performed best with a 4 blade. Maybe a different pitch for you would help. Hopefully other people can help out here.

jimmobius
06-16-2009, 01:56 AM
Well first of all, what is the max rpm you are running? Then where is the wake plate set at? How loaded is the boat? An 06 should have the cable throttle , you can check that to see if it is opening all the way ( engine not running and air cleaner off) . After that info what are the numbers on the prop? They are stamped on the prop by the nut on the shaft. I run a 13.7 x 16 acme prop 4 blade and it works great. I had a 13.7 x 17.7 oj ( factory) prop on it and had to prop down in pitch to get the boat to perform well at this altitude ( 5280' ) . Post your findings and maybe we can help. Jim .

jimmobius
06-16-2009, 01:59 AM
Well after reading your post again it sounds like you might have a low pitched prop. Let us know. Jim.

MOOMBA_97
06-17-2009, 09:37 AM
I can't really say what runs best on the V-drives. Mine is DD. I was a little concerned about the 11.5 pitch on my new one but after talking to OJ and Discount Inboard Marine they assured me it was better than the older 13x13. They were right.

Monty

LSM
06-25-2009, 02:37 PM
Thanks for the comments.

I've been busy the past week or so and haven't had a chance to check back with you guys on my prop research......

I haven't removed the nut yet to check the prop specifications. I plan to do that soon. I'm ready to hit the water again this weekend!

To answer a few questions:

I usually run the boat with 2 to 4 adults and 2 small children. (700 lbs max), plus a few boards and tool box. I consider that a fairly light load.

No ballast or fat sacks or anything like that.

Looking at my Perfact Pass, I'm running 26 -28 mph at 2800-2900 RPM's while cruising the lake. Mostly sight seeing and enjoying the lake.

The boat runs great. It just seems to use a lot of gas. I can leave the lake house with a full tank and travel 21 miles at 26-28 mph. As I return to the house the needle is a little above a half a tank.

I do know the needle is off a bit to the low side so I'm looking at burning at least a 1/3 of tank a gas or more on that one trip. That may be normal.....since that is a decent ride.....

I'm just thinking their may a better prop choice until my kids get a little older and really get into wakeboarding.....

Like I said, I'll have more info soon.......

Thanks guys...

maxpower220
06-25-2009, 03:07 PM
Fill your tank, run your boat and fill your tank. See how many gallons you are using to refill it compared to the size of your tank. Your gauge may be way off, mine is.

I have a 31 gallon tank. When the needle hits "E", I fill up with 12-14 gallons, meaning I have a lot of gas left.

LSM
06-25-2009, 06:17 PM
According to the owners manual it has a 40 gal tank. I ran it down to the needle was on E and I put 30 gallons in it. So I know it's off a fair amount.

With the 10 gallons it should indicate a fat 1/4 of tank.....

Having said that, my 21-22 mile trip is probably actually consuming a fat 1/3 tank of gas........In my case is 13.3333 gallons on a 40 gallon tank.

21 miles is a decent trip........Maybe that fuel consuption is normal.

yearround
06-25-2009, 07:08 PM
the fuel gauge is always a spot of contention for most people. if you happen to collect some cash from people for the ride, then you end up ahead, but i don't do that.

i prefer to watch the hour meter and monitor my fuel use. if we are riding and stuff, we will be at 4-5 gph, if we are cruising a long way at 25mph+ then i figure closer to 6 gph.

it sounds like this is similar to your use.

jester
06-25-2009, 07:14 PM
I have found for the first 20 gallons it is about correct. For the last 20 gallons it is off. I have also ran the needle below E and only put in 30 gallons to take it past F.

Sled491
06-25-2009, 10:23 PM
Back to the prop thing. I have a 13 x 13 stainless 4 blade that I bought from and old board member. I is not very smooth but works good. I dinged my stock 13 x 13 3 blade with about a month on the boat and had it fixed. Again not very smooth.

To be honest my buddies 13 x 13 brass seems very nice. I think I would like to go back to a CNC 3 blade from OJ or Acme. What are the results from that 13 x 11.5?

Gas guage, Mine was on E the other day. I grabbed 2 5gallon jugs and through them in and went for a ride. gas guage went to 3/4 tank. After about 1/2 hr of 5mph (my lake was shut down the other day due to high water) the gauge went down to 1/2. I would love an accurate gauge, but for now I just use it as rough estimate.

LSM
06-25-2009, 11:37 PM
the fuel gauge is always a spot of contention for most people. if you happen to collect some cash from people for the ride, then you end up ahead, but i don't do that.

i prefer to watch the hour meter and monitor my fuel use. if we are riding and stuff, we will be at 4-5 gph, if we are cruising a long way at 25mph+ then i figure closer to 6 gph.

it sounds like this is similar to your use.

In my case it looks as though I can make a 21-22 mile lap around the lake cruz'n at 26-28 mph in 1 to 1.5 hours and burn 13 gallons of gas.

From that perspective it seems like a lot of fuel.............

I'm going to make this same run in a few weeks and collect more precise data..........I'll carry my GPS and find out for sure.

Sled491
06-25-2009, 11:55 PM
Man I wish I could make that kind of cruise. That's a lot of water.

zegm
06-26-2009, 12:12 AM
Sled,

We have the 13 x 11.5 but the LS is a heavier bigger boat. The MC had the 13 x 13 brass. All I can tell is that I don't have much over 40 -42mph, but it is smooth. I have thought of trying another 13 x 13 but I think that would make her very slow out of the hole.

LSM
06-26-2009, 08:21 PM
I checked my prop and I'm running a MVC HC OJ (13.7 X 17.05). I'll have to go back and look up what that size and pitch does for me. You guys can probably tell me.....

This is on a 06 LSV.

LSM
06-26-2009, 08:24 PM
Man I wish I could make that kind of cruise. That's a lot of water.

Lake Martin AL has a ton of water. You can ride all day and not see it all. 40,000 acres of water on this one lake (fresh water). It's an awsome lake.

jimmobius
06-27-2009, 12:13 AM
Hello again,
Your boat has the same prop I took off mine. I now keep that one as a spare low altitude prop . If you can run the boat wide open throttle safely with an average load check your maximum rpm on the tachometer. Do Not over rev the engine, keep it right at or just below the maximum revolution that is recommended by Indmar . If you cannot reach that rpm limit then it is suggested to reduce the prop pitch in order to reach that rpm. That should put engine in the recommended rpm power range when operating. It is the same affect as running your car in third gear at 30mph engine rpm is 2000 rpm instead of 2nd gear and 2500 rpm. I hope this info helps . If you really want to get technical you can buy a fuel flow gauge and it will read out in gallons per hour of usage. My friend has one on their houseboat and it works well in planning fuel usage. My 2cts worth. Jim.

BensonWdby
06-27-2009, 09:22 AM
Absolutely - do not use your fuel gage as a fuel gage. They are pretty worthless. My general guidline for gas is 6 gallons per hour when not loaded for wakeboarding. This is actually an old number I used with the outboard, but from what I can tell with the 5.7L carb in my 99 Mobius it seems close. There are so many variables I don't think you can really measure it very accurately.

My real method for monitoring gas consumption in the boat is keeping track of how many gallons I buy over a week/month. When I buy boat gas I always use a credit card and only buy boat gas during the transaction.

In reality - I never worry about it. I have an OJ 4 blade stock prop and an Acme 3 blade that my prop guy and mechanic said I would really notice the difference with - I didn't, but nice to have a spare ...

Have fun - and don't sweat the petty stuff...

kaneboats
06-27-2009, 09:24 AM
I know that if we put in and run up river (about 6 miles or so) and then run back with lots of boarding, surfing, tubing, etc. on the way up and back I'll use about 13-14 gal. I have a 25 gal tank so I just top off every time before we head out and then I never think about it again.

LSM
06-28-2009, 12:37 AM
Thanks for the info..........

Check out my new Thread in "Service"......My engine quit on me today and did not want to start. I wonder if this is part of my fuel consumption questions / problem?