Rabbit Top Speed
#1
Thread Starter
My Feedback: (57)
Rabbit Top Speed
Hi,
I was running my engine this weekend and noticed a leak undrneath, was getting around 128K top speed.
Took a quick look under the front cowl, the tee festo nut was lose, other than that the fuel line was a bit hard so I replaced it. Tighten the tee nut and did a bench run again. Leak was pretty much gone, but still a bit of dripping coming through the back, nothing like before though.
Engine starts fine, runs great, but tops out at 135K steady. ECU is V6, with max RPM set at 155K.
Trying to do anything simple I can before sending it.
Only other factor is that I am now running on diesel. Does this require a change of parameter in the ECU?
Also, prior to tightening the tee festo, I took it out for cleaning and saw the inlet fuel tube sticking out. Is that tube meant to be welded to the tee or is it a press fit when tee is tighten?
Should I just send it in?
Thanks,
David
I was running my engine this weekend and noticed a leak undrneath, was getting around 128K top speed.
Took a quick look under the front cowl, the tee festo nut was lose, other than that the fuel line was a bit hard so I replaced it. Tighten the tee nut and did a bench run again. Leak was pretty much gone, but still a bit of dripping coming through the back, nothing like before though.
Engine starts fine, runs great, but tops out at 135K steady. ECU is V6, with max RPM set at 155K.
Trying to do anything simple I can before sending it.
Only other factor is that I am now running on diesel. Does this require a change of parameter in the ECU?
Also, prior to tightening the tee festo, I took it out for cleaning and saw the inlet fuel tube sticking out. Is that tube meant to be welded to the tee or is it a press fit when tee is tighten?
Should I just send it in?
Thanks,
David
#3
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Join Date: Jan 2002
Location: North Port,
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Hi David:
Lets look at your questions one by one. First, the fuel leak at the T FESTO is not good. From what I read, looks like you have resolved most of the problem. There is an O ring type gasket which may have been compromised. I will check supplies when I return to my office on Monday. Will send you a pm for your ship to address.
Maximum RPM is set correctly based upon your statement;. First item to check is the pulse and percentage (%) which indicate the throttle /rpm response. Menu up one screen from the primary. Here you will see in the upper right corner, Pulse/%. With throttle trim and throttle stick full up (High position) pulse should be in the 1940 - 1980 range with % 100. If not, your turbine cannot reach wot. Retrain the Tx and ECU. If pulse and % are within range, the next step is to run the turbine slowly to full throttle. At full throttle, let it run until it reaches max throttle setting; Monitor temp during this exercise. If temp is at or near the high 700's to 800, the ECU will not let the fuel pump deliver the required fuel necessary for maximum rpm.
The use of Diesel fuel requires no changes to any parameter for operation. I have used diesel for more than 3 years with not one issue.
If after conducting the above recommended procedures you still have concerns, contact Jose Melendez who will handle the servicing of your
Rabbit.
Best regards,
Eric Clapp
Jet Central USA
Jet Central Turbines
Lets look at your questions one by one. First, the fuel leak at the T FESTO is not good. From what I read, looks like you have resolved most of the problem. There is an O ring type gasket which may have been compromised. I will check supplies when I return to my office on Monday. Will send you a pm for your ship to address.
Maximum RPM is set correctly based upon your statement;. First item to check is the pulse and percentage (%) which indicate the throttle /rpm response. Menu up one screen from the primary. Here you will see in the upper right corner, Pulse/%. With throttle trim and throttle stick full up (High position) pulse should be in the 1940 - 1980 range with % 100. If not, your turbine cannot reach wot. Retrain the Tx and ECU. If pulse and % are within range, the next step is to run the turbine slowly to full throttle. At full throttle, let it run until it reaches max throttle setting; Monitor temp during this exercise. If temp is at or near the high 700's to 800, the ECU will not let the fuel pump deliver the required fuel necessary for maximum rpm.
The use of Diesel fuel requires no changes to any parameter for operation. I have used diesel for more than 3 years with not one issue.
If after conducting the above recommended procedures you still have concerns, contact Jose Melendez who will handle the servicing of your
Rabbit.
Best regards,
Eric Clapp
Jet Central USA
Jet Central Turbines
#4
Thread Starter
My Feedback: (57)
Thank you Eric. EGT never exceeded 560, which I think at 135K sounds about right, so it looks like this is headed either towards the %pulse, or I may have a partial obstruction somewhere downstream of the fuel solenoid.
I will run again next weekend and take a look at the %Pulse.
I did see the oring, but it looked more like a flat washer. So yes, it may be worn out.
Thanks for your support.
David
I will run again next weekend and take a look at the %Pulse.
I did see the oring, but it looked more like a flat washer. So yes, it may be worn out.
Thanks for your support.
David
#5
Thread Starter
My Feedback: (57)
Eric,
I think problem solved. I checked the %pulse and it was showing 1906 at 80%. I had retrained the program earlier last week and must have missed something, and never thought about cross verification with the ECU. I then retrained the ECU to 1906 and 100%. I then added additional 10% throw to the transmitter and now I get 1950% pulse and 100%.
I think this solves the issue. Will test run next weekend and see how it goes, but I'm very positive.
Thank you so much!
David
I think problem solved. I checked the %pulse and it was showing 1906 at 80%. I had retrained the program earlier last week and must have missed something, and never thought about cross verification with the ECU. I then retrained the ECU to 1906 and 100%. I then added additional 10% throw to the transmitter and now I get 1950% pulse and 100%.
I think this solves the issue. Will test run next weekend and see how it goes, but I'm very positive.
Thank you so much!
David
#8
Join Date: Nov 2003
Location: Mexico CityD.F., MEXICO
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Eric,
I think problem solved. I checked the %pulse and it was showing 1906 at 80%. I had retrained the program earlier last week and must have missed something, and never thought about cross verification with the ECU. I then retrained the ECU to 1906 and 100%. I then added additional 10% throw to the transmitter and now I get 1950% pulse and 100%.
I think this solves the issue. Will test run next weekend and see how it goes, but I'm very positive.
Thank you so much!
David
I think problem solved. I checked the %pulse and it was showing 1906 at 80%. I had retrained the program earlier last week and must have missed something, and never thought about cross verification with the ECU. I then retrained the ECU to 1906 and 100%. I then added additional 10% throw to the transmitter and now I get 1950% pulse and 100%.
I think this solves the issue. Will test run next weekend and see how it goes, but I'm very positive.
Thank you so much!
David
Do not add more throw to the transmitter after training because you are risking that ECU goes to Fail Safe mode
Regards