Can seaweed damage my ski?

[Soldierx]

Hi. I was riding in the sea the other day and there must have been a tide because there was seaweed all around the port. I have never experienced this before and I have only been riding for around 15 hours in total. I had to ride over the seaweed to get to other areas. At one point i heard a strange noise from the engine or the impeller. I eased off on the power and then the noise disappeared. About 1 hour later I went over another patch of seaweed, this time I heard the same noise but when applying more power, it started to make a loud clicking noise. I could only go a maximum of 5mph, otherwise the noise would sound even worse. I drove it back to the port, somebody checked the bottom of the ski for me and found nothing. I took it back out to sea and it was working fine. I am just wondering why this happened and if its safe to ride over seaweed on a jet ski? Can seaweed be easily sucked in? It makes be very nervous now because I am worried about the same thing happening again and being stuck out at sea.

Also, I have limited experienced with jet Skis, I pay a storage service to clean and lift my ski in and out of the water when I use it at the port. Each time they put it in the water, they check a little thing on the back to make sure its tight. What exactly is this and what would happen if it wasn't tight?

 

[Coastiejoe]

You were experiencing "Cavitation"

Here is an easy way to understand what Cavitation is: When you floor a car and the tires spin, they loose traction but the engine is running fine, and at high RPMs. Cavitation is when the impeller looses "traction" and spins but the engine RPMs are high.

You can have cavitation caused by a few things. Bad wear ring, bent impeller, bad carbon seal allowing air to be sucked into the impeller..

So seaweed itself can't hurt the ski but it CAN cause damage if it gets sucked into the impeller and then is pushed into a cooling line. This would allow the engine to over-heat.

Imagine placing a plastic bag over the water intake grate... Same theory. You are in the water but no to little water is getting to the engine to cool it.

You do want to avoid things in the water as the impeller can easily suck them into the pump area. At a minimum, you will/can get cavitation.

 

[Sportster-2001-951C-Stock]

Yep, avoid seaweed if possible and if it's stuck in the jet pump it will impede flow and could cause some damage to the wear ring but would need to be a chunk of weed. Also the engine cooling can become plugged with bits of weed so watch engine temperature and back flush on trailer afterward.

Going slow when weed is in the pump is best til it clears out, don't "gun" it b/c that can cause damage.

I once had a bleach bottle sucked up against my pump intake, boat wouldn't move till I shut it off and the plastic bottle fell away.

 

[Soldierx]

I thought it used a closed loop cooling system so it would still be cooled regardless?