Walter's v-drive, blk with 1:1 gear ratio.............

[JGR]

I just purchased this boat used and it has no history since it was a bank repo.

I have been using it at about 5,000'. I cannot pull an adult water ski out of the water without dragging them. I understand that this boat should pull very hard out of the hole.

I have looked into a new propeller.

Today I was talking to a dealer about ordering a new prop and they asked me what v-drive and prop are on the boat. I have a black Walter's with a 1:1 ratio and a three blade 13x11.5. I was advised to re-gear the v-drive to a 1:5 ratio and then change out the prop to match. They said my overall performance would me much better with this combo and that my boat was originally ordered incorrectly by a dealer and should have come with a blu 1:50 gear case?

TWO QUESTIONS:

Does this make any sense at all to do? Would it be worth the additional money to convert the v-drive?

Has anyone here done this v-drive conversion or had it done?


Thanks much..................

[chpthril]

I would think that you would be looking at a couple grand to change the V-drive v's > $400 to re-prop. I would just re-prop first and then see. There are other TO's here that have the 1:1 in thier V-drives, so it seems it was an option. If this boat was originally intended for a customer that was going to use it a low altitude lakes, then the current setup was probably just fine.

If the prop is a 3-blade, i'll bet it's an ACME 525 (this # should be stamped on the hub). If so, then the 911 would be a possible choice (13.00 x 10.5 w/ .080 cup) but I would call ACME and get thier recommendation.

[Fast1911]

Don't you get more pulling power out of the hole with a 4 blade prop?

Assuming it is sized correctly

[chpthril]

^^^ Typically yes, the 4th blade gives in increase in surface area. I know when re-proping an I/O, you drop the Dia when going from 3 to 4 blades. I'd guess the theory would be the same for inboards, but i'm not about to guess on a 4-blade replacement for a 3-blade.

[Waterski-Rebel]

I have a 1:1 and live near Denver and have an ACME 911 prop. It puts me at 5850 RPM's WOT, and gives me a very nice hole shot. Top speed is around 44-45 MPH.

If I were you I'd call ACME, and see what they have to say. My guess is, the 911 would be a good prop for you too.

[JGR]

chpthril you are good. I just spoke to BILL at ACME Propeller, what a great guy. He said my boat should have a 525 (13x11.5) on it and that for 5,000' he would go with the 911 (13x10.5). He said I should see a big difference getting out of the hole. He went on to say that with a 1:5 reduction and a 1631 prop I would have better overall performance at altitude since the motor would not have to work as hard. He also said depending on the cost if a gear change could be done it may not be worth the cost.

He also mentioned that since I have a 22v I could not swing as large a prop as the 22ve due to clearance issues.
Probably a 1631 (13.50x14.25) at altitude and a 537 (13.50x16) at sea level.

Has anyone here changed out their gears? If so what was the cost?

Rebel that's interesting. I ran WOT with 3/4 tank, Taps at 3-4, and no passengers. With my 525 prop I ran 38-40 mph at 4,800 rpm's. I would think that going with the 911 I would loose more top end. If I could get the performance you are getting I would just buy the prop. What engine do you have?

I just called Walter Machine and they said the gear set can be changed out but they need the s/n (which I don't have and is a couple hrs away from me now) off the v-drive to tell me how hard it might be and what the cost would be.

Thank you...............

[bobbysky]

i'm running a 23v, at about 3000', with a 1:1 ratio too. I have the 525 as a backup and 911 as my main prop. I would think the 525 should pull a skier out just fine. Last night I had two people in my boat and 3050lbs in water, and it pulled out of the hole and planed just fine.

So I just find it hard to think that a smaller boat, 2000' higher wouldn't pull out a skier just fine. Maybe she needs a tune up, might want to check your fuel filter, or maybe the prop is dinged up.

I could be wrong about the elevation and maybe 2000' makes a huge difference. But none the less, I don't think you need to change out your gears, just prop it down to the 911.

[JGR]

Boat was just serviced a month ago when I purchased it. I'll pull the prop off at the end of the season and have it looked at. I leave the boat in the water but when I launched it the prop looked fine and no visible bents or dings.

And yes it is a SLUG out of the hole. Wake boarding is not a problem, just pulling an adult skier.

[bobbysky]

I'm not sure if these have a mass airflow censor like cars do, but if it doesn't it may have been setup to run at sea level. Might have your mechanic check that out.

[Waterski-Rebel]

I have the 335 HP Marine Power motor, basically the same as the 340HP.

If your boat has the wrong prop on it, you can gain both high end and low end by putting the proper prop on it. If it's close to the correct prop you one gain on one end.

I think you'll be much happier with the 911.

[chpthril]

I'm not sure if these have a mass airflow censor like cars do, but if it doesn't it may have been setup to run at sea level. Might have your mechanic check that out.

I think all these engines are Speed/Density and use a MAP and Baro sensor.

[bobbysky]

well then scratch that idea

[R&T Babich]

... And yes it is a SLUG out of the hole. Wake boarding is not a problem, just pulling an adult skier.

We had a similar issue with our 21V.
Definitely try changing to a lower pitch prop.
It made a huge difference for us.
I'm the adult skier that was having trouble and now I pop right out.
We only went down one prop size.
All our props are 1 1/8", LH rotation.
Call Acme - here's their props: http://www.acmemarine.com/prop-list_ski-boat.php

[JGR]

Thanks guys. I'm still going to get see if the gear set in the v-drive can be changed, and if so what the cost would be. But I think I will be going with the 911 prop that several of you have mentioned and is the one Bill at Acme also recommended.

[JGR]

My local dealer called me back with the cost for them to change out the gear set.

$600 parts and $600 labor

That's just too much for me to consider changing the gears at this time. But nice to know it can be done.

We are thinking of a an RZ4 in the near future so it wouldn't make sense to make this change at this time.

I"m still interest to know if anyone has been able to make this modification themselves?