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@Volffas It was mine, we had the tube tied to the back of the boat with it. my kido un tied the tube and didnt put the rope in the boat, it was tied to the oh shit handle behind the driver. Wife cranked up the boat to push it up on the beach more, didnt realise rope was there and the rest is history. I want to make a alarm that goes off when you turn on the key and before cranking that yells ROPE ROPE ROPE.
All that damage is hard to look at, but as far as an alarm goes, you could just take a piece of that cut up dock line and tie it to one of your keys. I bet you'd know what to look for every time you start your motors after seeing that.
Ok another update. I'm replacing the rubber hose with sq40 pvc, goes from the bearing to the through hull fitting (rubber hose was the weak link in the factory setup). I'll take it all outone more time to silicon both ends of the pvc and then start the fiberglass repair.
Surely there is flex in that area. No way I would go with something rigid. .....and I agree...over time, that PVC will likely become brittle and crack. The rubber isn't a weak link if nobody every has reported a problem with it. I know I've never seen one and I've read a lot of forum posts in the last 5 years.
You would be surprised how fast it gets brittle. It is mostly buried in walls with no real water pressure so it lasts forever or at least until you open up the wall a barely tap it with a hammer.
Ok guys I think that the reason Yamaha puts hose there is for ease of manufacuring. If there is flex im my boat in that area it would severly damage all the bearings for the pump shaft. Another reason for the pvc is alighning the through hull fitting. When it pushed through it took all of the fiberglass it was scewed too. I would never get the hole drilled it the exact spot, there is some wiggle room in the fitting but not enough for me to be comfertable with. Im a master mechanic by trade but not a robot like they use to drill most of the holes in our boats. The pvc will be siliconed at both ends and fiberglassed at the hull end, that way if need be I can take it out if it does crack. I dont see that hapening in my lifetime. Pvc is broke down by UV light from the sun and that area hardly sees the light of day. Wish I was home working on it now, But Im in Littlerock AR for some Army schools wont be home till Friday.
I think the rubber hose is for vibration dampening, a lot of vibration could possibly cause the p v c to fail. The intermediate shaft bearings are mounted on rubber . Just something to take into consideration.
I would put back whatever is OEM. Not a job you want to have to do twice especially after you glass that bad boy in. Has anyone else seen or heard of a failure like this before? If they are not common (by god I hope they aren't) then OEM is the way to go.
I would put back whatever is OEM. Not a job you want to have to do twice especially after you glass that bad boy in. Has anyone else seen or heard of a failure like this before? If they are not common (by god I hope they aren't) then OEM is the way to go.
Very common failure on waverunners that ingest objects. Kind of surprised it does not happen more with the boats. If this happened on my boat I would claim it on insurance to get a warranty on the fix in case the fix failed away from land.
This might be a stupid idea or maybe it has already been discussed...but has anyone ever thought about adding a screen over the intake grate? I assumed or always thought that is where the ropes are being sucked in. How much would that impact the water flow?
This! I also don't understand why there is no screen here, even a really course one to prevent big items like golfballs and ski ropes, surely something with a 1/2" mesh wouldn't restrict waterflow? Ive been really fortunate in that I have only sucked up 1 ski rope (our lake is super clean), and when I did the engine stalled almost immediately. Other than the occasional "weeds", nothing else.
@JetBoatPilot - Looks like another product for you to sell. . . . . Get some R&D going when you get back from VACA. I have a feeling you would sell them like hot cakes.
@JetBoatPilot - Looks like another product for you to sell. . . . . Get some R&D going when you get back from VACA. I have a feeling you would sell them like hot cakes.
Hmmm...Even with a 1"X1" square stainless mesh, it's 88% open and that's with the smallest wire gauge, it might need to be thicker. That means a 12% intake restriction. I bet you would see some performance loss. Time for some testing, who's game?
I think it would need to be under the intake grate (well, above really but I think you know what I mean) Pull off the grate and install mesh and then install grate with longer screws if necessary.
Very simply stated, a jet pump moving through water is a very complex system.
To simplify, refer to Rule 3 on your reference about pumps. The grates are specifically designed to a) avoid creating turbulence (or keep the flow laminar) and b) avoid restricting inbound flow (or create pockets with pressure that is too low). Both of these inputs are key to minimizing pump cavitation.
Now, if you intentionally did the opposite of my a) & b) above (as in: increase inbound turbulence and decrease inbound pressure), you will be increasing the chance of cavitation.
Unfortunately, the technical challenge of designing an inlet screen (a 2D design with many intersections and complex flow patterns) that minimizes inbound turbulence and maximizes inbound pressure is MUCH MORE DIFFICULT than designing a grate (a 1D design with no intersections and parallel flow patterns) to do the same.
