Fule Ramp Issue on Rhino
04-24-2011, 04:17 AM
#1
Thread Starter
My Feedback: (99)
Join Date: Nov 2002
Location: Suwanee,
GA
Posts: 707
Likes: 0
Received 0 Likes
on
0 Posts
Fule Ramp Issue on Rhino
Trying to diagnose a problem on a Rhino with a fuel ramp. Turbine starts on gas perfectly, starts to ramp RPM, slowly (seems to be slower then normal) gets to about 27K-28K RPM and starts going back down in RPM and sputtering a bit, so I manually have to shut it down. This happened 3 times and then finally went to "running", then flamed out during taxi.
Sounds to me like a fuel delivery issue of some sort. So time to start the process of elimination...
1) Fuel pump, go into test mode and first test the fuel pump with the supply line off the turbine. Pump spool up begins and the pump gets close to high RPM and then suddenly stops, is this normal? Or is it reaching some limit and shutting down?
2) No air or blockage in the lines that I can see.
3) Any idea what the symptoms are for a solenoid issue?
4) Separate issue, when I do shut it down or after the flame out its not going into cool down, any idea what is causing this?
What else should I check?
Its Easter and heading to Mississippi Afterburner on WED so need to get this fixed today if possible and Eric may be tough to get given the holiday. Thanks for the help!
Sounds to me like a fuel delivery issue of some sort. So time to start the process of elimination...
1) Fuel pump, go into test mode and first test the fuel pump with the supply line off the turbine. Pump spool up begins and the pump gets close to high RPM and then suddenly stops, is this normal? Or is it reaching some limit and shutting down?
2) No air or blockage in the lines that I can see.
3) Any idea what the symptoms are for a solenoid issue?
4) Separate issue, when I do shut it down or after the flame out its not going into cool down, any idea what is causing this?
What else should I check?
Its Easter and heading to Mississippi Afterburner on WED so need to get this fixed today if possible and Eric may be tough to get given the holiday. Thanks for the help!
04-24-2011, 05:08 AM
#2
RE: Fule Ramp Issue on Rhino
Good morning and Happy Easter Jim,
1) Yes, this is normal. The pump is reaching a limit and the ECU is shutting it down.
My guess is a battery issue. Perhaps changing ECU batteries to a fresh one just to eliminate this factor.
If not this, then the fuel solenoid. I had one go bad earlier this year but it is rare.
Hope that this helps.
Mike
1) Yes, this is normal. The pump is reaching a limit and the ECU is shutting it down.
My guess is a battery issue. Perhaps changing ECU batteries to a fresh one just to eliminate this factor.
If not this, then the fuel solenoid. I had one go bad earlier this year but it is rare.
Hope that this helps.
Mike
04-24-2011, 05:08 AM
#3
My Feedback: (10)
Join Date: Jan 2002
Location: North Port,
FL
Posts: 1,109
Likes: 0
Received 0 Likes
on
0 Posts
RE: Fule Ramp Issue on Rhino
Jim:
Please re-start then watch the following readings:
1. Temp during the start/ramp process
2. PW - please watch this as it will tell us what the fuel pump is doing
3. RPM & PW recorded at time of "slow down"
Is this new? We can adjust starter power at preheat which may help.
Your question 1. Yes fuel pump auto shuts down during fuel pump test when it reached pump limit
Your question 4. Normal. . .you opted to abort the start. You can turn the system off then on and auto cool will resume.. .or you can use your throttle stick to manually cool down.
Please advise.
Regards,
Eric
Please re-start then watch the following readings:
1. Temp during the start/ramp process
2. PW - please watch this as it will tell us what the fuel pump is doing
3. RPM & PW recorded at time of "slow down"
Is this new? We can adjust starter power at preheat which may help.
Your question 1. Yes fuel pump auto shuts down during fuel pump test when it reached pump limit
Your question 4. Normal. . .you opted to abort the start. You can turn the system off then on and auto cool will resume.. .or you can use your throttle stick to manually cool down.
Please advise.
Regards,
Eric
04-24-2011, 06:30 AM
#4
RE: Fule Ramp Issue on Rhino
Jim,
Another thing that came to mind....check the fuel solenoid plug for integrity. Last year at Kentucky I had a similar issue and Juan from JC had me check the plug. Turns out that one of the wires was broken at the connector. Replaced it with a JR connector and all has been fine. Also, I forgot to ask if you're using the ceramic ignitor or a glow plug.
Another thing that came to mind....check the fuel solenoid plug for integrity. Last year at Kentucky I had a similar issue and Juan from JC had me check the plug. Turns out that one of the wires was broken at the connector. Replaced it with a JR connector and all has been fine. Also, I forgot to ask if you're using the ceramic ignitor or a glow plug.
04-24-2011, 10:19 AM
#5
Thread Starter
My Feedback: (99)
Join Date: Nov 2002
Location: Suwanee,
GA
Posts: 707
Likes: 0
Received 0 Likes
on
0 Posts
RE: Fule Ramp Issue on Rhino
ORIGINAL: BluFox
Jim:
Please re-start then watch the following readings:
1. Temp during the start/ramp process
2. PW - please watch this as it will tell us what the fuel pump is doing
3. RPM & PW recorded at time of ''slow down''
Is this new? We can adjust starter power at preheat which may help.
Your question 1. Yes fuel pump auto shuts down during fuel pump test when it reached pump limit
Your question 4. Normal. . .you opted to abort the start. You can turn the system off then on and auto cool will resume.. .or you can use your throttle stick to manually cool down.
Please advise.
Regards,
Eric
Jim:
Please re-start then watch the following readings:
1. Temp during the start/ramp process
2. PW - please watch this as it will tell us what the fuel pump is doing
3. RPM & PW recorded at time of ''slow down''
Is this new? We can adjust starter power at preheat which may help.
Your question 1. Yes fuel pump auto shuts down during fuel pump test when it reached pump limit
Your question 4. Normal. . .you opted to abort the start. You can turn the system off then on and auto cool will resume.. .or you can use your throttle stick to manually cool down.
Please advise.
Regards,
Eric
Eric and Mike - thanks for the replies! OK I ran the turbine and Murphy's Law kicked in, no issue at the 27K-28K RPM level like before and it went right to running. I started it twice and neither time did it do what it was doing yesterday. I did fully charge the battery between yesterday and this morning, its a 2700ma pack and it took nearly 2000ma, so it was low but not dead by any means.
I do have a video of the start up and high-speed running so you can see the exact parameters while it’s running. I did hear what I thought was a compression stall near full throttle although the turbine was so loud the video did not pick it up. Eric could you please take a look at the video and let me know if you see something wrong. Like I said before I'm leaving for Mississippi on WED and really need this in 100% shape by then. I do have an extra fuel pump and solenoid if necessary.
http://www.youtube.com/watch?v=zu-ys4iZTjo
04-24-2011, 11:48 AM
#6
My Feedback: (10)
Join Date: Jan 2002
Location: North Port,
FL
Posts: 1,109
Likes: 0
Received 0 Likes
on
0 Posts
RE: Fule Ramp Issue on Rhino
Jim:
Battery that takes 2000Mah out of an available 2700 most likely was the culprit. When running, menu up to the second screen. Observe battery performance while exercising the throttle. Lot's of good info within this screen.
Also, have you checked the fuel filters. . .Remember my MB339 at Super Jets. . .flamed out during taxi out. Slimey gellike on the bag in the UAT and within the filter. Would not hurt to check these as well. Could be part of the issue. Algae laying on the bottom of the UAT until high fuel demand then it is sucked up to the filter.bag. Please check this.
You have the CNC machined compressor. . .unlikely this is a compressor stall. . .is the air flow clear to the turibne from the inlet? A good test would be to insert a blower and increase air on the ground. Could be a slight cavitation because the jet is sitting still.
Cheers,
Eric
Battery that takes 2000Mah out of an available 2700 most likely was the culprit. When running, menu up to the second screen. Observe battery performance while exercising the throttle. Lot's of good info within this screen.
Also, have you checked the fuel filters. . .Remember my MB339 at Super Jets. . .flamed out during taxi out. Slimey gellike on the bag in the UAT and within the filter. Would not hurt to check these as well. Could be part of the issue. Algae laying on the bottom of the UAT until high fuel demand then it is sucked up to the filter.bag. Please check this.
You have the CNC machined compressor. . .unlikely this is a compressor stall. . .is the air flow clear to the turibne from the inlet? A good test would be to insert a blower and increase air on the ground. Could be a slight cavitation because the jet is sitting still.
Cheers,
Eric
