Starting a jet boat out of water

JeffSteele

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May 22, 2022
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Had an outboard before and always had to attach water hose to out drive water pickup to make sure impeller wasn’t ruined. How do you start a jet boat out of water? I have a used jet boat now and getting ready to start it, just want to make sure I don‘T damage something.
 

kenny nunez

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Jun 20, 2017
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Had an outboard before and always had to attach water hose to out drive water pickup to make sure impeller wasn’t ruined. How do you start a jet boat out of water? I have a used jet boat now and getting ready to start it, just want to make sure I don‘T damage something.
Look to see if there is a “T” fitting in the hose between the pump to the front of the engine. If not then add one that has a female garden hose connection with a male plug to close it when running in the water. You want water going back through the pump and water going through the engine.
The engine may get warmer than usual because most of the water will go to the pump.
 

JeffSteele

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May 22, 2022
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Look to see if there is a “T” fitting in the hose between the pump to the front of the engine. If not then add one that has a female garden hose connection with a male plug to close it when running in the water. You want water going back through the pump and water going through the engine.
The engine may get warmer than usual because most of the water will go to the pump.
There are two water hookup’s, one for each motor I assume. I guess the main thing I’m wondering about is when to turn the water on. I heard I should start the engine before turning the water on. Not sure why it wou make a difference. Any insight into this would be helpful.
 

kenny nunez

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I always like to turn the water on first. I was a Berkeley, Jacuzzi dealer.
Which jet drive do you have?
 

JimS123

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The Owner's manual for the engine(s) should show the port for a water hose pickup. If you don't have the manual, buy one.

Jets are an entity all in themselves. Sending water to the engine with it not running can send water to the cylinders and thus hydrolock the engine and thus turn a good engine into crap.

Anyone that knows anything about these motors understands that you start the engine first, turn on the water, and then turn off the water and then lastly turn off the engine.

If you screw up and forget the proper sequence, simply pull the spark plugs, remove the seat, hit the starter and watch the fountain of water shooting in the air coming from the waterlogged cylinders......
 

JeffSteele

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May 22, 2022
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The Owner's manual for the engine(s) should show the port for a water hose pickup. If you don't have the manual, buy one.

Jets are an entity all in themselves. Sending water to the engine with it not running can send water to the cylinders and thus hydrolock the engine and thus turn a good engine into crap.

Anyone that knows anything about these motors understands that you start the engine first, turn on the water, and then turn off the water and then lastly turn off the engine.

If you screw up and forget the proper sequence, simply pull the spark plugs, remove the seat, hit the starter and watch the fountain of water shooting in the air coming from the waterlogged cylinders......
Thanks, that’s pretty much what I am hearing. Just wanted to make sure I didn’t mess it up.
 

QBhoy

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Mar 10, 2016
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Always start engine first. Then water on. Stop water…then engine off.
Wouldn’t run them for too long, or too frequently, out the water. Not great for them.
 

Big Gee

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Jun 29, 2011
Messages
173
The Owner's manual for the engine(s) should show the port for a water hose pickup. If you don't have the manual, buy one.

Jets are an entity all in themselves. Sending water to the engine with it not running can send water to the cylinders and thus hydrolock the engine and thus turn a good engine into crap.

Anyone that knows anything about these motors understands that you start the engine first, turn on the water, and then turn off the water and then lastly turn off the engine.

If you screw up and forget the proper sequence, simply pull the spark plugs, remove the seat, hit the starter and watch the fountain of water shooting in the air coming from the waterlogged cylinders......
This is how I've always done it and I've never had a problem.
Definitely purchase the oem service manual if you can, it's well worth the money.
 

JimS123

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Always start engine first. Then water on. Stop water…then engine off.
Wouldn’t run them for too long, or too frequently, out the water. Not great for them.
One other comment to add. Before starting the engine, spray the impeller and wear wing with water.

That procedure is also in the manual.
 

undercover500

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Apr 21, 2022
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42
Is there anything hurt by running them dry for maybe 30 seconds? I know with an outboard there's a rubber impeller, but unsure with a jet.
 

QBhoy

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No. You’ll be fine. But as suggested above. Not too long. If you are in the salt…always a good idea to start them dry on the slipway to expel any water sitting in there before you flush at home or similar with fresh.
 

JimS123

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No. You’ll be fine. But as suggested above. Not too long. If you are in the salt…always a good idea to start them dry on the slipway to expel any water sitting in there before you flush at home or similar with fresh.
The Winterizing procedure calls for 3 throttle "pushes" to expel water that could freeze. When I do it, I may run the engine for 5-7 seconds. Running without water for 30 seconds would make me cringe.

The possible problem is overheating. Besides, what would be the purpose of running it that long?
 

QBhoy

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The Winterizing procedure calls for 3 throttle "pushes" to expel water that could freeze. When I do it, I may run the engine for 5-7 seconds. Running without water for 30 seconds would make me cringe.

The possible problem is overheating. Besides, what would be the purpose of running it that long?
Tend to agree with you there. No real reason I can think of. Despite likely not it being long enough to overheat in reality. But not sure I’d run it for that long either.
 

PWH1

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Jan 11, 2010
Messages
78
Had an outboard before and always had to attach water hose to out drive water pickup to make sure impeller wasn’t ruined. How do you start a jet boat out of water? I have a used jet boat now and getting ready to start it, just want to make sure I don‘T damage something.
After use it is recommended you start the ski for no more than 10-15 seconds and give the throttle a few pulls to push water out of the exhaust. I usually do 5-8 seconds 3/4 quick rips and off.... Also when running the ski out of water in the driveway/etc the procedure/order of steps has to be followed to ensure you do not flood the ski with water. See your manufacture manual for these directions
 
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