Leading Edge Twin Impellers: Review Thread

[anmut]

Starting a review thread for others considering the upgrade to the twin impeller design by Leading Edge. Here's the link to the impellers I purchased for my 2020 212S: Yamaha 212 Twin Force Impeller

Boat specs at time of this review:
270 hours on motors
3 people
Full gas
500lbs of lead
Dual AGM house batteries
Yesterday was our first run of 2025, just a shakedown run to start the season. I ran a stretch of the Wisconsin River near our home which was still flowing a lot of water from spring rain.

Notes (my percentage estimates are just guesstimates based on the previous 270 hours I've used this boat):

• First thing I noticed pulling out of the dock, and later running at speed, is that with these impellers the tone of the jet pumps is lower. Before it was much higher pitched at any RPM, but the twins have a deeper tone.
• Hole shot - I'd say a 20% improvement to plane with these impellers.
• Idle/No Wake 1,2,3 - nothing to report (as expected)
• Cruising speed - I was able to cruise at 30mph at about 200 - 400 less RPM, leading to a lower cabin noise RPM
• MPGs - We ran about 20 miles last night, against the current and back with the current. 50% was WOT speeds. Initially it appears I've picked up .3 mpgs - usually my MPG average is 1.7, yesterday it was 2 MPG average. I confirmed this when I filled up at the gas station on the way home.
• Top speed: Since adding the lead and batteries a couple of years ago I lost about 3mph off the top end. Best I've ever seen on this boat was 51 on a calm day and just me in the boat. Last year I hit 47 top speed all year. With the new impellers i hit just under 46. Funny story though, our initial cruise from the dock always goes up river, so upon my initial WOT run I was only hitting 41 mph, which was very surprising. It took me a few miles to remember I'm pushing up against a decent down river current... duh!
• Turning hook-up: I did some WOT testing of the boat turning at speed and I easily picked up 30-40% more hook/power through hard corners. I want to test this further, on more open water (this part of the river is pretty narrow), but I did not have any cavitation and, while I still lost some speed on a sharp port/starboard turns, it was significantly less than before. Bottom line here - my nephews that like to go tubing behind my boat are really in for some pain this season.
• Surfing/wakeboard: TBD - water was only 61f in the channel and I didn't feel like putting my wetsuit on.

I did have an issue on the water, potentially related to the new impellers. After driving up river about 8 miles we stopped and had a snack. When I went to get back on plane from that pause, I had my bilge light come on and it started pumping water out. I got off plane and started the normal check in the engine bay. Thankfully no hoses were disconnected and bearings weren't leaking water.

I then headed back down to our sandbar, another few miles down river. Did some WOT pulls in that time frame and bilge eventually stopped shooting out water. When I got to the sandbar I opened the cleanout plug hatch and it was FILLED with water. I'm talking like the entire hatch was a lake, inches above the ports and drain.

Pulled the plugs and drained the water. About an hour later we left the sandbar and went back to the dock. After I got the boat on the trailer I pulled the boat out of the water and just slightly up the ramp so I could reach the plug and the boat still had a heavy list down ramp.

Pulled the plug and had tons of water pushing out. I lifted the hatch and it wouldn't go up - the gas strut had become disconnected from the bow side mounting point and had extended itself into and under the bow side hatch lip.

When I got home I unscrewed the hatch hinges and reattached the strut and got that fixed. Now, I'm not sure if the water in the hatch caused the strut issue or if I somehow screwed up when I put my sand anchors away and it popped the strut off. I'm leaning towards my error on that one - but something to watch.

The next thing I did was take the garden hose and force water down into the cleanout drain. I think the drain may have been clogged. I didn't notice any draining at the sandbar and, after cleaning it and filling the hatch with water on the hose, it appeared to drain very quickly with a noticeable vortex. Question: if the drain under the swim deck is under water, the drain should still function, right? I've been racking my brain on that one...

My hypothesis is that the new twin impellers are loading the pumps earlier in the pump tunnel, which is forcing water past the cleanout plugs at a higher rate. Last year, unless we were surfing, my cleanout plugs would have only inches of water in them and the boat was dry. On yesterday's run, I think the water was coming in at such a high rate, along with the clogged plug, that it was pouring into the boat through the cleanout tray.

We're going out again this weekend so we'll see if the drain can keep up with the water past the plugs. It's also clear to me that I need to seal those cleanout ports and plugs better. I'm going to try the o-ring as suggested by another member, and also inspect the entire system back there for loose or unsealed areas.

Other than the water intrusion, I'm very happy with the upgrade. Heck, the lower tone of the pump noise was worth it alone!

 

[FSH 210 Sport]

The clean out tray and plugs;
It makes sense there would be pressure / more pressure with an inducer impeller ahead of the main impeller.
Do you have the tray sealed around the perimeter?
I realize the water was or may have been above the mechanical access hatch?
Do you have the hatch riser?
Are the clean out plug seals in good shape? I see your boat is a 2020 model, have you replaced the seals yet? Do you put any wax on the seals?
It sounds as if the drain line could have been clogged, and yes the water will still drain out of the clean out tub if the lower drain is below water, maybe not as fast as if the drain was out of the water. Hopefully the drain was clogged by a pesky spider or mud Dobber.

The lower tone / noise level of your pumps is consistent with my experience with a single screw impeller, Skat Trak, that wasn’t producing cavitation or far less than stock, In my experience the Skats produced half the noise of the oem impellers at cruising speed, a 3DB decrease. Further, the cruise speed taking less rpm and the increase in mpg is evidence of more efficiency out of the pumps.
Call your experience a huge win.

The hole shot is consistent with all reports I’ve heard about the twin screws.

Top speed is always a bit of a compromise with lower speed performance, sounds as if your numbers are good.
Were WOT rpm’s the same as before?

Good luck on the upcoming test!

 

[anmut]

The clean out tray and plugs;
It makes sense there would be pressure / more pressure with an inducer impeller ahead of the main impeller.
Do you have the tray sealed around the perimeter?
I realize the water was or may have been above the mechanical access hatch?
Do you have the hatch riser?
Are the clean out plug seals in good shape? I see your boat is a 2020 model, have you replaced the seals yet? Do you put any wax on the seals?
It sounds as if the drain line could have been clogged, and yes the water will still drain out of the clean out tub if the lower drain is below water, maybe not as fast as if the drain was out of the water. Hopefully the drain was clogged by a pesky spider or mud Dobber.

The lower tone / noise level of your pumps is consistent with my experience with a single screw impeller, Skat Trak, that wasn’t producing cavitation or far less than stock, In my experience the Skats produced half the noise of the oem impellers at cruising speed, a 3DB decrease. Further, the cruise speed taking less rpm and the increase in mpg is evidence of more efficiency out of the pumps.
Call your experience a huge win.

The hole shot is consistent with all reports I’ve heard about the twin screws.

Top speed is always a bit of a compromise with lower speed performance, sounds as if your numbers are good.
Were WOT rpm’s the same as before?

Good luck on the upcoming test!

Much appreciate the response!

Cleanout tray/hatch:
- I had sealed everything last year with silicone, but will be redoing it all this week.
- I do not have the riser because I need the space for my sand anchors
- Cleanout plugs in good shape - I guess that's relative to pump pressure LOL! I looked at the Jet Boat Pilot rebuild kits and did some searching on this forum last night. The rebuild kits are $80 per for just the lower and the rubber seal - ouch ( I know I know, break out another thousand). Also, another forum member mentioned that he used the rebuild kit and it didn't improve anything. So before I order them, I'm going to try the o-rings (purchased this morning) and look at the seals.
- Plugged drain was weird - always possible something clogged the line, but we don't have mud dobbers here in WI that I'm aware of. Could've been some other critter while the boat was in storage.

Regarding WOT RPMs - port was 72xx and stbd was 74xx - that's consistent with my years of owning the boat. I've checked the cabling on the throttles and my oil levels are good - just the way this boat is and, because I don't run WOT that often, it doesn't bother me.

 

[FSH 210 Sport]

Much appreciate the response!

Cleanout tray/hatch:
- I had sealed everything last year with silicone, but will be redoing it all this week.
- I do not have the riser because I need the space for my sand anchors
- Cleanout plugs in good shape - I guess that's relative to pump pressure LOL! I looked at the Jet Boat Pilot rebuild kits and did some searching on this forum last night. The rebuild kits are $80 per for just the lower and the rubber seal - ouch ( I know I know, break out another thousand). Also, another forum member mentioned that he used the rebuild kit and it didn't improve anything. So before I order them, I'm going to try the o-rings (purchased this morning) and look at the seals.
- Plugged drain was weird - always possible something clogged the line, but we don't have mud dobbers here in WI that I'm aware of. Could've been some other critter while the boat was in storage.

Regarding WOT RPMs - port was 72xx and stbd was 74xx - that's consistent with my years of owning the boat. I've checked the cabling on the throttles and my oil levels are good - just the way this boat is and, because I don't run WOT that often, it doesn't bother me.

Right on…. Sounds like you’ve got your stuff together on this. Interestingly it’s usually the port engine that spins a little faster.

Make sure the groove at at the bottom of the well is super clean as well as the walls of the well are clean so the seals can seat against clean surfaces.

 

[kgower]

Right on…. Sounds like you’ve got your stuff together on this. Interestingly it’s usually the port engine that spins a little faster.

Make sure the groove at at the bottom of the well is super clean as well as the walls of the well are clean so the seals can seat against clean surfaces.

I concur. Our port engines rpms are always about 200 more.

 

[anmut]

Right on…. Sounds like you’ve got your stuff together on this. Interestingly it’s usually the port engine that spins a little faster.

Make sure the groove at at the bottom of the well is super clean as well as the walls of the well are clean so the seals can seat against clean surfaces.

Good call!