WTF!!!!!

[swatski]

Yep. Both engines on. I also tried using my ridesteady to gradually increase speed to try to get up to speed or even plain

Any chance you can get her on the trailer and inspect the pumps, flashlight from the rear - through the steering nozzle. I had something like this a couple of times, with somewhat similar symptoms, the boat still runs but just not as strong thrust. Hard to see from the back, not visible through the intakes or cleanout access at all


EDIT: Never mind - saw the post above.

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[John Mcpartland]

Any chance you can get her on the trailer and inspect the pumps, flashlight from the rear - through the steering nozzle. I had something like this a couple of times, with somewhat similar symptoms, the boat still runs but just not as strong thrust. Hard to see from the back, not visible through the intakes or cleanout access at all
View attachment 76834

EDIT: Never mind - saw the post above.

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It looks pretty clear. Since day 1 it never really felt right to me. Coming from an i/o I thought it was just because it was a jet boat and it took a long time to (hook up). It has alway sounded like you were loosing second gear in a stick shift.

 

[swatski]

View attachment 76830 View attachment 76831 View attachment 76832 View attachment 76833

could be the picture, but is it possible your impeller's OD (outside diameter) is off - if you have a gap that is ;arge, really just not very snag fit, basically less than a credit card thickness - that could be, at least in part, an issue?

 

[swatski]

Coming from an i/o I thought it was just because it was a jet boat and it took a long time to (hook up).

No, that should not be the case. She should be jumping out of the hole like a raped ape when you hit it WOT from a dead stop.
Something is definitely off.

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[John Mcpartland]

No, that should not be the case. She should be jumping out of the hole like a raped ape when you hit it WOT from a dead stop.
Something is definitely off.

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Never has.

 

[Bruce]

@John Mcpartland,

The top impeller picture appears to show a bend in one of the impellers which would change the pitch. Both impellers look not terrible but rough. I believe there may be a visible wear pattern from cavitation.

I agree with @swatski on the gap between the housing and impeller. There should be a spec for that gap in the owners manual. I suggest checking the gap with a feeler gauge all the way around on both pumps.

If the impellers are the problem that is unlikely to be a warranty claim. You may want to diagnose it yourself.

 

[swatski]

Never has.

I would check the impeller clearance for sure. Heck, maybe they fitted the wrong (pitch) impellers in your boat?
Don't quote me but it should be - the blade clearance gap between the impeller edge and the intake liner something like 0.03 inches.
If it is larger - that would definitely explain performance loss.

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[swatski]

The top impeller picture appears to show a bend in one of the impellers which would change the pitch. Both impellers look not terrible but rough. I believe there may be a visible wear pattern from cavitation.

You may be used to looking at the MR-1 impellers (which we know are much nicer and sharper looking !), the 1.8s with those long blades - they can look a little scruffy, even new. I can tell you these impellers look about as good as mine right now. Yes, not perfect - but I would not think that would explain the performance loss that is described. I think.

EDIT: Yeah, you right, maybe there is some cavitation damage. I really think maybe the OD is the culprit here.

 

[Bruce]

I assumed that 1.8 impellers would be at least as pretty as these new MR-1 impellers. And to be clear @swatski is a well studied expert. I am just making guesses.

 

[swatski]

I assumed that 1.8 impellers would be at least as pretty as these new MR-1 impellers. And to be clear @swatski is a well studied expert. I am just making guesses.

View attachment 76839

I don't have any pictures handy of the clearance, but it should be really tight, almost touching, and almost no light coming through.

But, as far as the appearance, the 1.8 impellers always look a bit off... with imperfections and small bends, here are two brand new impellers - hard to show in pictures though. No problem with performance though, in fact when pitched and ODed correctly - those are the best for the 1.8 boats.




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[Beachbummer]

Since you are taking pictures, can you put the boat in forward and take a picture of the pumps from the rear?? The gates should be fully out of the way.

 

[Julian]

Even with a gate slightly in the way she should take off like a bat out of hell. If she never did there is a problem.

 

[scokill]

So we bought our AR240 last june and it just never seemed run right. I just thought it was me being new to jet boats, I had posts about not being able to surf with 3 adults and 4 kids under 10 in the boat. We couldn't get the boat to plain. Fastforward to today, we had 5 adults ( the largest,me at 208) and 5 kids under 12 and the couldn't get above 16mph at 8k rpm. At the end of last season i filled all the gaps in yje intake and sanded smooth thinking that may be the problem, obviously not. Any ideas? I'm going to take it into the dealer tomorrow?
Thanks
John

What did the dealer say?

 

[bronze_10]

If people are not sitting down u should be able to throw them out of the boat when u punch it... Just reserve that for the people u don't like!

 

[captras]

View attachment 76830 View attachment 76831 View attachment 76832 View attachment 76833

Upper right hand corner of the first pic. ...is that a piece of wood jammed between the impeller blade and the housing? I have had exactly that happen. ..small piece but jammed so tight the blade would not move.

 

[Gym]

I agreee with @swatski & @Bruce. The first thing that caught my attention was the large gap between the impeller and liner. I have replaced my liners with oem. When I completed the job they looked too close but when I checked the clearance with a feeler gauge they were perfect. My point being, the clearance is so tight it's almost hard to see. Someone should be able to dig out the clearance spec for your boat. A quick check should confirm our suspicions.

 

[Andy NJ]

Debris?

 

[BigN8]

When you run the engines on the trailer, do the impellers sound like they are not rubbing or grinding on the outside walls? Like, is it a real clean sound? Because if the clearance is correct it should sound horrible. Almost a metal on metal sound.

 

[John Mcpartland]

What did the dealer say?

My dealer is closed on sunday and Monday's, I have to wait until tomorrow to take it in

 

[Adrian @ JB Solutions]

I had a few issues with my '17. Different issues... but the point is.. let the dealer handle it and enjoy the boat once you get it back!