Does Wet Slipping equal Loss of Power?

[Five Faces]

I have been wet slipped in fresh water this summer and there is some algae growth on the hull and on the Jet nozzles.

Recently I have experienced a significant loss in power. Early in the summer I was running mid/upper 40’s mph with 4 peeps at 7K rpm, today I could NOT go any faster than 28 mph under the same circumstances???

I expected that there would be some reduction in performance, but NOT that much. Opinions if that is the issue, or do I have something else going on?

I did pull the plugs on the clean out ports and it felt as if they were clean, although it felt as if there was some minimal algae growth there.

Any wet slippers experience this extreme performance loss due to algae growth on the hull and impeller?

I finally get my lift in a couple weeks, can’t wait, woo-hoo!!!

 

[OrangeTJ]

I'm willing to bet it your problem is growth on the hull. Had pretty much the same issue with my SX210 the first year I wet slipped it. It's important to pull it out every so often and thoroughly clean the hull.

 

[212s]

I have been wet slipped in fresh water this summer and there is some algae growth on the hull and on the Jet nozzles.
Recently I have experienced a significant loss in power. Early in the summer I was running mid/upper 40’s mph with 4 peeps at 7K rpm, today I could NOT go any faster than 28 mph under the same circumstances???

Growth on the hull will affect speed, but I wouldn't think it would be a 20mph drop. I would think maybe something is in the impellers causing greater loss?

 

[Five Faces]

Maybe the thin layer of algae growth on the impellers and wear ring in addition to the hull?

 

[mwalker4]

Last time I wet slipped I had a dramatic slow down until I started taking it to the Lake beach and wiping off once a week. It was an I/O. One waverunner I wet slipped did not get enough use for a bit and developed a clog in the cooling system.

We have our name in the lottery for a slip next year, but I kind of hope we don't get one. This boat is so nice and clean, almost brand new. It stays in the garage and the only cover I have is the shipping cover. I guess I need a lake house with a lift.

 

[gallobg]

I wet slip mine in a fresh lake, and have to pull it ever 2-3 weeks to clean the hull. Otherwise I also have a performance hit. It's not as dramatic as yours though. Last time I pulled it I was around 41mph max, after cleaning it got back up to 46mph (AR195).

Algae and other hull clingers really do seem to impact performance on these hulls. Sometimes you need to pull the boat to really see what's going on. If you've been in the water a lot you might also check to make sure the impellers / pumps are completely clean, and that the mechanicals are working properly. For example, make sure the reverse buckets are completely open. Or if you have steering add-ons (Cobra or Thurst Vectors) make sure they're not stuck causing extra drag. I have also found that the algae can also cause interference with these types of things too. One last option could be to check the water intake strainers at the nozzle to make sure enough cooling water is getting through to the engines, although that's lower on the list of possible suspects.

 

[mark_m]

Yep! Buy some oxalic acid on amazon, mix it up then spray down the boat. Watch the slime come right off! Wax when done.

 

[Julian]

Yup.....growth on you hull will slow you down. My boat here in NC will go from a top speed of 50 down to 37 when its been sitting in the water for weeks. This didn't happen anywhere near as bad when I lived up north, so your location and growth varies depending on where you are and what is growing. This is why I ended up getting an air dock because I was burning through tons of gas driving a dirty boat (to go 20mph, my RPMs had to be significantly higher etc).

 

[Damsroy]

Agreed with @Julian. Depends on your location.
my boat is wetsplipped here in CT and I have no significant growth. No change to top speed between beginning and end of the season.

 

[Five Faces]

Yup.....growth on you hull will slow you down. My boat here in NC will go from a top speed of 50 down to 37 when its been sitting in the water for weeks. This didn't happen anywhere near as bad when I lived up north, so your location and growth varies depending on where you are and what is growing. This is why I ended up getting an air dock because I was burning through tons of gas driving a dirty boat (to go 20mph, my RPMs had to be significantly higher etc).

I'd be happy with 37 mph, I'm starting to think something else is going on.

 

[Julian]

I'd be happy with 37 mph, I'm starting to think something else is going on.

How much crap is there growing on it? My was really "furry" but I don't think it ever dropped below 30mph at its worst. Does the boat cavitate at all? I'm wondering if there is either something in the impeller, or if you are missing intake caulk.

 

[Five Faces]

How much crap is there growing on it? My was really "furry" but I don't think it ever dropped below 30mph at its worst. Does the boat cavitate at all? I'm wondering if there is either something in the impeller, or if you are missing intake caulk.

I checked the impellers through the clean out ports, nothing. Ill have to use the search function regarding the intake caulk, but I was definitely mid-40's mph in early July.

 

[OrangeTJ]

Furry hull will cost you a lot of performance, but like others have said, yours sounds a bit worse than normal. Mine got to where it would go maybe 32, down from a top speed in the mid 40s, and it was bad furry. Question: Are you still getting full rpm at WOT? If not, dollars to donuts you need to swap out your spark plugs. For some reason, these boats go through plugs very quickly.

 

[Five Faces]

Furry hull will cost you a lot of performance, but like others have said, yours sounds a bit worse than normal. Mine got to where it would go maybe 32, down from a top speed in the mid 40s, and it was bad furry. Question: Are you still getting full rpm at WOT? If not, dollars to donuts you need to swap out your spark plugs. For some reason, these boats go through plugs very quickly.

Great question...For the life of me I can't remember what full RPM was at WOT, I was out yesterday and was getting upto about 7K, I just can't recall what it was back in July when it was performing well. I may swap out anyway since I don't know when it was done last, I've only owned the boat since May.