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2016 scarab 195ho impuse RPM fluctuation

wango tango

Jet Boat Addict
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michigan
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Scarab
Year
2017
Boat Model
HO Impulse
Boat Length
19
hi everyone,
New to jetboaters.net and this is my first post! love the site !
I just bought a new scarab 195 ho impulse in march and now have 15 hrs on it as of now runs great but have one issue with it that i did not have on my seadoo speedsteer 155 (nonsupercharger). At about 3200 rpms, the rpms pulsate down 150 to 200 rpms , asked the dealer tech. about this and he said that it was the supercharger coming in and out at that rpm and its normal for the rotax supercharger.
I do get full RPMs 8100, max speed of 44 mph


Has anyone experienced this or know if the dealer is correct?
 

Rtimleck

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Location
Springwater, Ontario
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Scarab
Year
2014
Boat Model
HO Impulse
Boat Length
19
I do experience something similar at the same RPM. I also was told it had to do with the supercharger.
 

Pirana

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TX
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Scarab
Year
2016
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HO Impulse
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25
So there is a clutch to activate the SC?
 

wango tango

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thanks for the input guys,
so is it a bad thing to keep the engine at that rpm(3200) and the supercharger clutch coming in and out?
 

Ron@Scarab

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Scarab
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2017
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HO Impulse
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If the motor is running, so is your supercharger, it's a constant, just like the jet-pump and impeller. The clutch on the shaft of the supercharger is for any excess load. You can't activate it, it is mechanical. The RPM fluctuation that you're referring to is usually due to a dirty injector from what we have found.
 

wango tango

Jet Boat Addict
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Scarab
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2017
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HO Impulse
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19
If the motor is running, so is your supercharger, it's a constant, just like the jet-pump and impeller. The clutch on the shaft of the supercharger is for any excess load. You can't activate it, it is mechanical. The RPM fluctuation that you're referring to is usually due to a dirty injector from what we have found.
If the motor is running, so is your supercharger, it's a constant, just like the jet-pump and impeller. The clutch on the shaft of the supercharger is for any excess load. You can't activate it, it is mechanical. The RPM fluctuation that you're referring to is usually due to a dirty injector from what we have found.
thanks ron , my problem would be the dealer saying there is nothing wrong,(wilson marine ,MI)
 

wango tango

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If the motor is running, so is your supercharger, it's a constant, just like the jet-pump and impeller. The clutch on the shaft of the supercharger is for any excess load. You can't activate it, it is mechanical. The RPM fluctuation that you're referring to is usually due to a dirty injector from what we have found.
ron,
also want to add that this a new boat this march with only 15hrs on it now.
thanks for feed back
 

Ron@Scarab

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HO Impulse
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Welcome to the Scarab family! 15 hours is not a lot of hours. Hopefully, you have completed your 10 hour inspection/service. If not, start there first. Otherwise, look into what I have stated.
Have a good weekend!
 

wango tango

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Thanks,
just love the boat
At dealer now, find out soon

I miss It already!¡!!
 

wango tango

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Bad gas was my issues, even though I bought rec. gas , I guess you still can get lower octane with it.
I'm filling up with shell premium and boat is back to normal.
I love this boat, not as fast as I like but it's fine!
 

wango tango

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It still comes and goes, engine didn't do it for the first half of summer . It does run great with BP or SHELL gas 87 or 93.
Talked to some seadoo boat owners with same engines and they also get fluctuating rpms with no answer.
Don't put additives in gas it will run worse and could cause issues, don't need it on these EFI engines, waste of money.
It's not a issue, if it happens I get out of that RPM range.
High humidity temperatures makes a big difference in performance.
Overall it ran Awesome this year.
 

gRobi

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2018
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215 ID
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Same here. Runs smooth and to 8000 rpm but having the fluctuation at arround 3300 sometimes.

Does it on 95 and 100 octan.
 
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