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I made my own "Lucky 13" style pump cones...

gmtech16450yz

Jetboaters Captain
Messages
291
Reaction score
566
Points
217
Location
SF Bay Area
Boat Make
Yamaha
Year
2017
Boat Model
Limited S
Boat Length
21
I bought a Lucky 13 pump cone back in 2017 for my GP1800 and it made tuning that ski way easier. But as much as I wanted them on our 212 Limited S, I just couldn't see spending the $700-$800 to do it. (They really should give some kind of break on things like that if you need to buy two of them for your one boat.)

So after doing a modification to the rotary table on my mill, I realized I would now be able to make a couple of these cones myself. It took a few days but I was able to pull it off! The 3 degree angle the base of the cones are at made it a little tricky. I was thrilled when I bolted up the first one and it was centered in the jet nozzle perfectly. Since I made these on a manual mill and lathe, without a DRO even, it's not like I could just select "TWO" in a CNC program and make another. So I ended up making the second one slightly smaller diameter and a tad shorter. The larger one will go in the port pump, the smaller one in the starboard. So I won't have to put 3 washers in one side and 0 in the other, they'll already be somewhat compensating for the uneven pumps we deal with in these boats. (Hopefully, I just finished them and have yet to put the boat in the water.)

Of course this is a "don't try this at home" kind of post, but at least for those that have the skills and/or access to a machine shop, it can be done. As always with my silly projects, I had fun and learned a bunch in the process.
 

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How awesome!!!! That's pretty cool. Looking forward to your updates on how they work.
 
I've had the boat out once so far with the new cones. They did exactly what I expected, they provide me with a way to tune the pump pressures and engine rpms. (I have water pressure gauges that show me the pump pressures.)

One cone and base I made turned out to be the perfect size, the other was a tad too big/long. I put the other cone and base back on the mill and thinned it down a bit. I also made two more cones with a different shape, a little more blunt shaped, not a straight angle like the first set. I think they might work even better, we'll see next time out.

I did end up opening up the nozzles themselves, something that's pretty standard when you use the cones. They were 85mm, I took them all the way out to 88mm. That gives me more headroom/adjustability with the cones. One of the cool things about these cones is you can tune for altitude. So I wanted to make sure I can remove washers from the cones when I'm at a high altitude lake so I can get the engine rpms back up. So at sea level I'll always run a couple washers, otherwise I'd be over 8k. Should be perfect!

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The price is high for a twin setup. I went with these.
I don't think anyone other than Lucky 13 makes cones for the 3 bolt pumps though.

You brought up a good point though, are they worth the almost $800 a pair of Lucky 13's would cost? I'd say no. Definitely not for the Joe average boater. Especially not for the NA engines. They are a little more effective on the supercharged engines because they already have larger nozzles and they have the power to overcome the restriction the cones create. The NA engines are effected way more by anything taking power and will lose more top end rpms and speed with these cones. That in itself may be why Lucky 13 is the only one making cones for the NA pumps.

They aren't something that you're going to bolt on and go faster or make your boat work better. They almost always require modifying the nozzles larger. How many of you want to grind away at your boat nozzles? Probably not many. I'm not your average Joe kind of guy. For me, a lot of the time it's the journey and not the destination. Challenging myself to machine these bases and cones was incredibly rewarding for me. They may look fairly simple, but machining the 3 degree angle isn't easy without a 5 axis CNC machine. Even something as simple as making the o ring grooves is tricky and easy to screw up. I have a manual mill and lathe, I don't even have a DRO on either (digital read out that shows you the exact position of the cutter and material). I do most everything by hand and eye. So making these cones wasn't so much about making some incredibly amazing change to my boat, it was all about pushing my abilities and learning. At 63 I think that's a pretty freaking amazing thing to still be able to do! So this thread wasn't so much about the silly cones, it was about doing things you might not think you're capable of. Never stop pushing yourself to learn.

This is an example of me challenging myself to do things I've never do before. Yesterday I made a base for my downrigger. Instead of welding the plate to the round bar, I wanted to bolt it together. The rod holders at the back of my boat are at a 14 degree angle. So to make the downrigger sit flat I needed to make the plate sit 14 degrees from the rod. To do it I rotated the head of my mill to 76 degrees and did all the facing, drilling and tapping sideways. It worked and I learned more about my mill's capabilities. It was a good day!

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