Robert Sands
Jet Boat Addict
- Messages
- 155
- Reaction score
- 57
- Points
- 117
- Location
- Toronto Canada
- Boat Make
- Scarab
- Year
- 2015
- Boat Model
- HO Impulse
- Boat Length
- 19
Hi everyone,
I like keeping you all updated, so I thought I would write about my last jet boat mistake. I recently sucked up a rock, a decently large rock. It was about 1.75" diameter by 0.5" thick. It slipped right through the grate lengthwise and started to make a horrible sound for about 1 second that sounded like throwing marbles into a blender.
I was traversing a shallow section of the lake and paying attention to my Navionics for depth, as well as the boat itself for it's depth gauge. But, I was going 30mph and for a brief second had glided over a very shallow section of lake that caused me to suck the rock up. I didn't see that section on the map, and the boat was moving too fast to register it on the dash; it wouldn't have mattered anyway. I went back and the water was probably only 15" deep.
As soon I heard it I knew what happened and I emergency stopped, threw it in neutral and turned the engine off. Unsure if I was ok or not I started the boat up and all seemed good. But, with only a little throttle applied the boat began to immediately cavitate and shake violently. Even someone not used to a jet boat would have turned it off. The shaking felt like the entire boat was violently vibrating.
So, out came the scuba mask, flippers and flashlight and under the boat I went. Luckily (I think) there was no damage to anything, just the rock lodged in between two blades of the impeller; much too big to get sucked through. The vibration I was feeling was the impeller that would have normally been in balance now drastically out of balance. The rock itself was full of gouge marks as if hitting it with a knife. Upon closer inspection the blades of the impeller seemed fine. No blunted edges, no nicks, no scrapes, no bending.
The newest addition to my emergency (stuff that goes wrong under the boat) kit is literally a spare tire jack set from a GMC Sierra 1500. The tools in that kit are long, strong, and let me pry at the impeller all the way back from outside the grate. In about 2 tries I had the rock out.
Like I said, I inspected for damage and bending or whatever I could find. There were no other rocks or issues so I came up. I hesitantly turned the boat on and all seemed fine. I slowly feathered the throttle forward fearing the worst and I heard and felt nothing out of the ordinary. I tested speed, 43mph, no issues.
Since then I've had it out for about 9 hours with no issues or loss in performance. No leaking into the hull through the seals, nothing.
The moral of my story, be careful in shallow water. For some reason I thought that since we were moving so fast maybe something off the bottom of the lake in shallow water would get stirred up and I would be at a safe distance away from it before it had time to find its way through my intake grate. I've taken risks before like that in shallow water, this time it happened and I didn't even know I was taking the risk. More experience for you through my screw up.
I like keeping you all updated, so I thought I would write about my last jet boat mistake. I recently sucked up a rock, a decently large rock. It was about 1.75" diameter by 0.5" thick. It slipped right through the grate lengthwise and started to make a horrible sound for about 1 second that sounded like throwing marbles into a blender.
I was traversing a shallow section of the lake and paying attention to my Navionics for depth, as well as the boat itself for it's depth gauge. But, I was going 30mph and for a brief second had glided over a very shallow section of lake that caused me to suck the rock up. I didn't see that section on the map, and the boat was moving too fast to register it on the dash; it wouldn't have mattered anyway. I went back and the water was probably only 15" deep.
As soon I heard it I knew what happened and I emergency stopped, threw it in neutral and turned the engine off. Unsure if I was ok or not I started the boat up and all seemed good. But, with only a little throttle applied the boat began to immediately cavitate and shake violently. Even someone not used to a jet boat would have turned it off. The shaking felt like the entire boat was violently vibrating.
So, out came the scuba mask, flippers and flashlight and under the boat I went. Luckily (I think) there was no damage to anything, just the rock lodged in between two blades of the impeller; much too big to get sucked through. The vibration I was feeling was the impeller that would have normally been in balance now drastically out of balance. The rock itself was full of gouge marks as if hitting it with a knife. Upon closer inspection the blades of the impeller seemed fine. No blunted edges, no nicks, no scrapes, no bending.
The newest addition to my emergency (stuff that goes wrong under the boat) kit is literally a spare tire jack set from a GMC Sierra 1500. The tools in that kit are long, strong, and let me pry at the impeller all the way back from outside the grate. In about 2 tries I had the rock out.
Like I said, I inspected for damage and bending or whatever I could find. There were no other rocks or issues so I came up. I hesitantly turned the boat on and all seemed fine. I slowly feathered the throttle forward fearing the worst and I heard and felt nothing out of the ordinary. I tested speed, 43mph, no issues.
Since then I've had it out for about 9 hours with no issues or loss in performance. No leaking into the hull through the seals, nothing.
The moral of my story, be careful in shallow water. For some reason I thought that since we were moving so fast maybe something off the bottom of the lake in shallow water would get stirred up and I would be at a safe distance away from it before it had time to find its way through my intake grate. I've taken risks before like that in shallow water, this time it happened and I didn't even know I was taking the risk. More experience for you through my screw up.
