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Jet cat P20sx Trouble.

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Jet cat P20sx Trouble.

Old 11-01-2016, 03:24 AM
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tisdall_80
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Default Jet cat P20sx Trouble.

Gents,

I've got a P20sx in a Habu 32x and seem to have no end of trouble with excessive flames on startup, Failed starts and occasionally hot starts.. Has anyone had similar trouble?? Any advice would be appreciated.. Cheers
Old 11-01-2016, 05:33 AM
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Len Todd
 
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Does the P-20 act up when out of the Plane on the bench? If not, then what distance do you have from the exhaust cone to the pipe?
Old 11-01-2016, 07:10 AM
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lov2flyrc
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Most likely cause is too aggressive on the ramp cycle. I suggest you give the guys at Intairco a call, they should be able to walk you through Boss Mode access so you can increase the ramp time parameter. We usually set this parameter around 38-40 on the P20 for smooth, consistent starts. Factory setting seems to be a bit to aggressive for hot / humid / high altitude environments. Another possibility is a worn starter oring or a failing starter motor but unlikely the cause unless the engine has some time on it.
Old 11-01-2016, 08:38 AM
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Vincent
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I would start by lowering the uaccel 1 setting
Old 11-01-2016, 05:52 PM
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tisdall_80
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Originally Posted by Vincent View Post
I would start by lowering the uaccel 1 setting
Hi Vincent,

How do I adjust this. Can't seem to find it..

Cheers
Old 11-02-2016, 10:51 AM
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Plug in your gsu and turn on the system. select limits and then +. this screen should look like this. my setting is 225...what does yours say??
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Old 11-02-2016, 11:08 AM
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On Most JetCat engine models I would agree with Vin, Uaccel 1 would help based on your description but our service experience with the P20 has shown this type of start issue needs to be adjusted in the Accelr Ramp parameter.
You need to access the boss mode by using this button sequence: Ignition - Manual - Run - Min/Max
Then go to the pump menu and change the Accelr Ramp to 38 or 40.
Old 11-02-2016, 12:19 PM
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Originally Posted by lov2flyrc View Post
On Most JetCat engine models I would agree with Vin, Uaccel 1 would help based on your description but our service experience with the P20 has shown this type of start issue needs to be adjusted in the Accelr Ramp parameter.
You need to access the boss mode by using this button sequence: Ignition - Manual - Run - Min/Max
Then go to the pump menu and change the Accelr Ramp to 38 or 40.
Hey Todd I agree 100% on the ramp adjustment I just figure its good to check the U1 setting too. A few years ago when the P20 first came on the market I owned 2 of them and I had to adjust the U1 down to where it would NOTstart then go one click up at a time until it lit off, lock in that setting and the motor would start beautifully every time.
Vin...
Old 11-02-2016, 04:57 PM
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Mine says U-Accelr1 :0.400 and U-Idle: 1.06
Old 11-02-2016, 05:06 PM
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tisdall_80
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Originally Posted by lov2flyrc View Post
On Most JetCat engine models I would agree with Vin, Uaccel 1 would help based on your description but our service experience with the P20 has shown this type of start issue needs to be adjusted in the Accelr Ramp parameter.
You need to access the boss mode by using this button sequence: Ignition - Manual - Run - Min/Max
Then go to the pump menu and change the Accelr Ramp to 38 or 40.
Hi . Thanks for the info.. I can't my GSU to access the Boss mode using your sequence??

Cheers
Old 11-02-2016, 05:44 PM
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Originally Posted by tisdall_80 View Post
Mine says U-Accelr1 :0.400 and U-Idle: 1.06
.400 is extremely high even .300 is on the high side. Put that number down to .200 and start there.
Vin...
Old 11-03-2016, 02:53 AM
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I have run dozens of P-20's and never adjusted the Ramp, but we are near sea level.
But 0.4 is normal for a P-20, the pump is completely different, Url2 around 1.16

Videoing a start would give us all more info
Old 11-03-2016, 09:09 AM
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As Dave mentioned, a .40 on Uaccel 1 is fairly normal for the P20 pump. I have serviced several P20's over the past few months exhibiting the same symptoms, the ramp adjustment described being the appropriate fix. Watching the GSU during the start sequence, if the RPM's get to 40-45K then start to fall off, the issue is in the Accelr Ramp parameter; Ramp being slightly too aggressive causing a rich condition, combustion begins to moves aft and the engine cant accelerate without starter assistance (which disengages at 45K).
Old 11-06-2016, 05:29 AM
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I am also facing a similar start issue on my P20, Todd can you clarify entering boss mode as I wasn't able to get to the pump parameters either. Do you hold all four on initial battery connection (power up) to enter boss mode?
Old 11-07-2016, 07:11 AM
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Please provide the software version of your ECU to confirm correct button sequence.
Old 11-07-2016, 01:37 PM
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It's running 10.1B
Old 11-09-2016, 11:33 AM
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Todd -

MY ECU is running software version 10.1b, can you tell me what the key sequence is on that version.
Old 11-09-2016, 11:46 AM
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Hold down the Manual key during power-up, then press these buttons in the following sequence: Ignition - Manual - Run - Min/Max. Then go to the pump menu and change the Accelr Ramp to between 38 to 40.
Old 10-03-2020, 01:07 PM
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My p-20-sx have same problem and accelr ramp is 20.0

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