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Lucky 13 ( L13 ) Anti-Cavitation Cone Install / 2016 AR240

swatski

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The way the L13 works is pretty simple. Basically, it increases the efficiency of the pump by increasing pressure and thrust.

I have previously installed and tested a Lucky 13 in a single engine 190, but it is a long thread. https://jetboaters.net/threads/anyo...ce-adjustable-pump-cone-in-a-boat.7967/page-2
Needless to say, I liked it so much I decided to get those for the new 240.

THE RESULTS
I love those cones. Have not done any tweaking or tuning at this point (here, with the new boat), just installed the cones using all 3 spacers provided and ran around a bit to see how it feels. Hard to describe the effects, but the boat handles "tighter" and accelerates better, which is due to improved pump loading. Top speed and RPM are the same, but speed can be improved by tuning the cone and the impeller/venturi. I have NOT done ANY tuning here, yet the boat runs noticeably better with the L13 (strait out of the box) than w/OEM cones.


L13s were sourced from greenhulk store https://www.4-tecperformance.com/index.php?main_page=index&cPath=207 Those are very high quality parts. The base is tapered 3deg, but it is hard to see in the pics. It has 3-bolt base (distinct from SVHO that has 4).



The hardest part (!) was getting the OEM grease (called "EPNOC grease AP #0" or "EP") for the pump bearing. I wanted to stay with the OEM grease. After a long search found the US equivalent ("Mobilux™ EP 0") here:
https://redidriver.com/my-redi-driver-store/8-oz-ep-0-grease-for-redi-driver-free-shipping-in-usa/
upload_2017-1-2_0-40-47.png


INSTALL
First step -- pulling the pump. This has been documented elsewhere, but here are few quick easy steps that I follow, same/similar on both sides:
upload_2017-1-2_0-58-44.png
Note that my boat has the additional (port side) steering rod (from @Cobra Jet Steering LLC). A long wrench extender comes in handy to reach 4 main (also long) bolts that hold the venturi segment.


Don't loose those pesky dowels (there are 2):
upload_2017-1-2_1-0-47.pngupload_2017-1-2_1-1-2.png


Note that at this point the stator (pump bearing housing) segment of the pump can be pulled out, along with the impeller and the shaft. However, there is no need to do so for this particular mod.

The OEM cone is attached w/ 3 allen bolts/washers that are reused in L13. There are notches in the OEM cone that fit a flat screwdriver for prying the cone off. The aluminum flange is soft and there is an O-ring on the inside that can be damaged, so proceed carefully, these are critical parts for pump maintenance:
upload_2017-1-2_1-5-22.pngupload_2017-1-2_1-5-39.png
Here, there is no evidence of water intrusion, and everything looks fine inside this housing.


Here are the two cones side-by-side. Quite a difference in size! Note, the base of the L13 has smaller cavity.
IMPORTANT - the OEM O-ring needs to be moved from the OEM cone to the base of the L13 (red arrows):
upload_2017-1-2_1-6-39.pngupload_2017-1-2_1-21-19.png


Here comes OEM grease, it is semi-liquid. I used approx. 2oz. of new grease per cone. Ambient temps are low, but even at room temp this stuff is easy to handle and not too runny.
upload_2017-1-2_1-9-57.pngupload_2017-1-2_1-21-31.png


The base of the L13 is tapered and it is important to install it with the small engraved letter "T" towards the top (which will center the cone inside the venturi):
upload_2017-1-2_1-12-50.png
(The "top" bolt is OFF center to the left, in both pumps)


The base needs to be separated from the "cone" to gain access to bolt holes. I use a bit of LockTite on the allen bolts since the base stays in the pump. There is a small O-ring, and the spacers can be loaded and exchanged WITHOUT removing the base. This is very important - once the base is on, spacer adjustments can be made without exposing the critical pump bearing.
upload_2017-1-2_1-14-36.pngupload_2017-1-2_1-14-49.png
upload_2017-1-2_1-15-1.pngupload_2017-1-2_1-15-11.png


Running on single engines, each gets the boat to 30+ mph (up from approx. 25mph with OEM cones).
There is still a lot of cavitation running with one engines. The L13 can not prevent this although it does help.
upload_2017-1-2_1-24-30.png


Top speed and RPM are unchanged in my boat with this setup, running at about 50-52mph top. This can be further tuned, either for higher speed or better hole shot/acceleration.
upload_2017-1-2_1-25-30.png


Done. There will be more tuning and testing, TBA.

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Last edited:

buckbuck

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Alright, you piqued my interest. I don't think I have any problems with cavitation but I will be returning to this thread as you tune and test.
 

buckbuck

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While you are at it, why don't you install some reddish orange LED's in the cone to simulate a Bat Boat turbine.
 

Mainah

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@swatski - You have certainly got the bug bad. Great write up with good photos. I have not seen the Lucky 13 instructions but they may want to use yours. Do you think ambient and water temperature is going to make a difference in tuning? Keep up the great work with all of your mods.
 

Rod5

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Bravo!! This is a great write up @swatski! I didn't realize how relatively simple this mod was. I'll be watching carefully your future trial tests with different spacer combinations too.
I now have a noticeable increase in cavitation slippage when trying to pull-up a skier with full ballast and 5+ people onboard since doing the ribbon delete in combination with removing the air box boots. The ribbon delete created noticeably more mid range power which seems to more easily break loose the screws with very heavy loads where stock trim only had minor cavatating slippage under the same very heavy loading.
I wonder if cold air and cold water temps will skew the winter time testing and "best" setup results much when comparing to summer time "best" setups.
 

swatski

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@swatski - You have certainly got the bug bad. Great write up with good photos. I have not seen the Lucky 13 instructions but they may want to use yours. Do you think ambient and water temperature is going to make a difference in tuning? Keep up the great work with all of your mods.
Cooler temps help our motors, no doubt, and prop slip/cavitation in our boats is much like loss of traction in a car, gets worse with more power (w/no traction control), so we will only be making less power when it warms up.
I doubt ambient temps affect cavitation of the pump per se (much).

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swatski

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Bravo!! This is a great write up @swatski! I didn't realize how relatively simple this mod was. I'll be watching carefully your future trial tests with different spacer combinations too.
I now have a noticeable increase in cavitation slippage when trying to pull-up a skier with full ballast and 5+ people onboard since doing the ribbon delete in combination with removing the air box boots. The ribbon delete created noticeably more mid range power which seems to more easily break loose the screws with very heavy loads where stock trim only had minor cavatating slippage under the same very heavy loading.
I wonder if cold air and cold water temps will skew the winter time testing and "best" setup results much when comparing to summer time "best" setups.
@Rod5 Thanks for your comments, very helpful, I think you totally nailed the issues.

That is exactly what happens, and if after the ribbon/snorkel delete one adds even more power (such as w/ ECU reflash) cavitation/prop slippage becomes even more of an issue. More power is good, but only if one can harness it.

Thinking of wake surfing w/big ballast/people loads, cavitation becomes a limiting factor at some point. The L13 is a step in the right direction but, like many performance mods, it's an incremental step not a silver bullet. Ultimately we would need dual-impeller assemblies and such, but at that point one might as well buy a dedicated wake boat, LOL, so I'm hoping this can be avoided. I love the versatility of our Yammies.

As far as cold/warm months setup, yes it is a huge difference when you are talking performance. 52mph in the winter months can easily become 47mph in the heat/humidity of the summer. Same with elevation. But, the great thing about the L13 is I can always take out a spacer or two (with the boat on the trailer, working through the nozzle opening, no pump disassembly required) if my RPMs or speed drop when the weather gets hot.

However, so far I have not seen ANY DROP even with all 3 spacers in! I was actually quite surprised. I might actually add another (2mm) spacer to the port L13 (which at that point is all that could fit given the bolt length, and the cone not protruding out). This is definitely good news, as I don't see any need to bore the venturi opening (something that would offset RPM drop if I experienced that) at this point -- I have the opposite problem (not bad). If the additional spacer in the port cone still does not drop the RPM, I might pull that impeller and touch it up (i.e. bend/smooth the blade, maybe 1-1.5mm) on the trailing edge to give it slightly more aggressive angle, which is fairly easy.

EDIT: On that last point, this is exactly what THE FACTORY used to do for us! (pitching the port impeller more aggressively than the starboard), but for whatever reason they stopped doing it.

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Bruce

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I am surprised by the 25/30 mph speed on one engine and 50 mph top speed. In comparison my loaded down SX230 tops out at 18 mph with one engine idling and the other full throttle with trim tabs fully deployed and would not even plane without the tabs while top speed is 47.
 

swatski

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I am surprised by the 25/30 mph speed on one engine and 50 mph top speed. In comparison my loaded down SX230 tops out at 18 mph with one engine idling and the other full throttle with trim tabs fully deployed and would not even plane without the tabs while top speed is 47.
I know, right? Not making it up though.

I think if you removed all the rum barrels from your bootlegging operation under the deck, you would be doing 60mph, LOL.

But seriously, I just went back through my notes and dug up some vids and stills and -- yes, definitely was doing 25mph on one engine, either one. Not something I would want to do for a long time, but it got up to those speeds (25mph with port at WOT, strbd at idle, NO L13):
upload_2017-1-2_23-8-38.png
(similar results for both sides)

One caveat of course -- testing in a river on different days -- impossible to keep same time same direction, etc. some current/wind/whatever. That said, I was doing 52mph with two engines at WOT on that day, which is the same as what I was getting with the L13s installed now. So -- I think the ratio of max speed at WOT on one engine to max speed at WOT on both engines should be fairly objective. That makes the 31mph on one engine at WOT the other at idle (WITH L13) really shine, doesn't it?
Here, WITH L13:


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So is the cone just making the jet stream more laminar?
 

swatski

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So is the cone just making the jet stream more laminar?
The higher volume of the Lucky 13 cone increases performance. So, L13 increases the efficiency of the pump by increasing pressure (and thrust), hence the reason adding spacers increases volume and subsequently increases performance (to a point, you can't add so many spacers as that will kill RPM), need to find the happy medium for best performance (since it makes it harder for the impeller to force water through, it can reduce RPM).

As for the laminar flow, I don’t know the answer. As you control the RPM (to an extent) by adding/removing spacers, the cone moves towards/away from the venturi nozzle opening, in effect reducing/increasing the path through which water can exit. L13 has a gradual taper design, I believe they tested many other shapes and sizes before settling on the production design. I believe a straight cut cone (the angle from the base to the tip is perfectly straight) or "top shaped" (or buckled) led to big speed loss over the production cone shape in their testing.

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Thats cool. I wonder if I can build some. Essentially a cover out of nylon that goes over the stock cone. Something to think about. Thanks for the writeup. Cam.
 

swatski

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Rodney Findley

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So just to be clear, adding spacers increases top end?
 

swatski

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So just to be clear, adding spacers increases top end?
Not necessarily. The fastest skis run with L13 but it takes a lot of tuning. The primary purpose is improving pump efficiency and anti-cavitation. If only care about speed, this would not be my first mod, it would be air intake.

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robert843

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So I understand this didn't increase the top speed but would it make a cruising speed achieved at a lower rpm? Is 35 mph the same rpms before and after?
 

swatski

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So I understand this didn't increase the top speed but would it make a cruising speed achieved at a lower rpm? Is 35 mph the same rpms before and after?
That is exactly the case, albeit I have no records of testing at 35mph with/out the L13. But the general trend is unmistakable - same speeds are achieved at lower RPM with L13. We are not talking any huge gains, but it is substantial enough to feel it in your boat's handling.
To me, the differences were more pronounced in the single engine (190) which cavitate a lot more out of the hole.
With the new 240, the most convincing/palpable difference was in the test of running on a single engine - big difference - gain of acceleration and speed with L13.

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For the L13 to be effective it needs a good amount of tuning. After days on the water I have found it to increase top speed also, but the props needed to be re-pitched to achieve this. At the same RPM as I was turning before I was actually a MPH faster with better holeshot, but it took re-pitching the prop to get me dialed in. I would recommend staying around 5-6-7mm of spacers. 6mm worked best for me. It helps cavitation a bunch. I would imagine a 1.8L SVHO engine in a Boat with a Fizzle IC and a Tune would need a L13 for sure. Period. R3 or Riva Vtech, Fizzle IC with cooling upgrade kit, and a nice 4inch air intake and I bet the L13 is a must on a Boat. Spin it 8500RPM and I would love to see what a single 1.8L would do. My FZR ran 86 and pulled so hard it was silly. A single Engine boat would be a great build. Anyone?
 
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