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Cylinder Drop Test

R502

Well-Known Member
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Scarab
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2015
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HO Impulse
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Just curious as to the cylinder drop test performed via BUDS software. Is this test an injector disable to ensure integrity of fuel cut off capability at each individual injector? Is it performed because the fuel cut off of these injectors is known to be an issue after so many hours of use? Can the same test be performed with Candoo by shutting injectors off individually while motor is being test run? I see by a couple of videos out there that the mechanic is listening for the motor to change RPM while performing the drop test, and individual fuel cut off is the only thing I can think of as far as what you would be looking for.
 

Ron@Scarab

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HO Impulse
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Just curious as to the cylinder drop test performed via BUDS software. Is this test an injector disable to ensure integrity of fuel cut off capability at each individual injector? Is it performed because the fuel cut off of these injectors is known to be an issue after so many hours of use? Can the same test be performed with Candoo by shutting injectors off individually while motor is being test run? I see by a couple of videos out there that the mechanic is listening for the motor to change RPM while performing the drop test, and individual fuel cut off is the only thing I can think of as far as what you would be looking for.
If the engine RPM drops when clicking on a cylinder, the injector and the ignition of that cylinder are functioning normally. If it doesn't drop, then it isn't operating properly. By Clicking on the injector, you can hear it click several times showing that it's working. If you can hear the injector, it is okay! I have never seen an injector go bad on a Rotax unless it was submerged. They are pretty well designed. I use a place in Tampa called Pro-Flow to clean any injectors for any brand. You always want to put the PWC or jet boat in drowned mode to prevent a huge backfire when trying to re-start.
 

R502

Well-Known Member
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Thanks for the answer. I had an idea it wa to test cylinder function but was not sure. Much appreciated.
 

Ron@Scarab

Jet Boat Addict
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Thanks for the answer. I had an idea it wa to test cylinder function but was not sure. Much appreciated.
Any time!
 

Ronnie

Jetboaters Fleet Admiral
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I have to ask, what is drown mode?
 

Ron@Scarab

Jet Boat Addict
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HO Impulse
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I have to ask, what is drown mode?
It is a feature that shuts off fuel and spark when you have to de-water your motor!
 
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