mm130b Posted May 14, 2011 Share Posted May 14, 2011 Tail pipe vibration during high power run.i change eng rear mount,check upper mount & lower mount torque.also change tail pipe & torque check.blade angle ok.others parameter ok. please anyone can help Quote Link to comment Share on other sites More sharing options...
pjvr99 Posted May 14, 2011 Share Posted May 14, 2011 Turbine blades missing ......... Quote Link to comment Share on other sites More sharing options...
Lkuest Posted May 14, 2011 Share Posted May 14, 2011 Ask'em what #1 and #4 are doing ;) Quote Link to comment Share on other sites More sharing options...
mm130b Posted May 15, 2011 Author Share Posted May 15, 2011 Ask'em what #1 and #4 are doing #3 engine vibrate. Quote Link to comment Share on other sites More sharing options...
Waldo Posted May 15, 2011 Share Posted May 15, 2011 If you see it vibrate it is low frequency, either the AC Generator rotor unbalanced (replace and retry) or your torquemeter is unbalanced. Rgds Quote Link to comment Share on other sites More sharing options...
Ben Legere Posted May 16, 2011 Share Posted May 16, 2011 Have you tried balancing the prop? A prop balance won't do much for helping but it's a good place to start. Check 5th and 10th to see if the compressor is shifting, the truss mounts are good to look at too, I have found a few cracks in them in the past... A sig run will narrow it down for you if you have the equipment. Good luck Quote Link to comment Share on other sites More sharing options...
Lkuest Posted May 16, 2011 Share Posted May 16, 2011 Ask'em what #1 and #4 are doing Was a bit of a joke. I figure if you can't see the outboard motors, and they make it out ok, then tailpipe vibes are a bit of a comfort item to look at. Here's what I got for a vibe. If the vibe is in the tailpipe only, and not in the throttle or condition lever: Check tailpipe for proper installation Inspect front engine mounts (i'd just change them and be done with it. Sometimes the inspection lies.) Inspect rear engine mount (already changed it, right?) Borescope turbine (-15 engines can throw a rotor blade and you wouldn't be able to tell otherwise) If no defects were found, then the tailpipe vibe is within limits, and I dare anyone to try to create a limit with a ruler. If the tailpipe vibe is accompanied with a throttle or condition lever vibe, then this is what I got: Perform a propeller loose blade inspection Perform a propeller blade tracking inspection Inspect prop afterbody, torque retainer assembly, and front spinner for loose or damaged components Check propeller hub nut for proper torque (replace RGB if out of limits) Check prop shaft vertical movement and end-play Check rear engine mount (already changed) Check prop balance If no defects are found, replace propeller These are only recommendations, of course. You can complete them in any order. Checking the wing truss mounts like Ben said couldn't hurt, as well as checking the engine sloping longerons and tie struts as well. You should also look at the maintenance history. If either the engine or propeller have been changed just before the problem started, suspect shipping damage or improper installation of either the engine or propeller or other major structural components. Sometimes, a throttle vibe is normal, and a tailpipe vibe is normal, it's your call. Just pretend like you are going to be flying on the plane and make sure you look at anything that would make you want to land as soon as possible. Quote Link to comment Share on other sites More sharing options...
alioman Posted March 30, 2012 Share Posted March 30, 2012 we had same snag on our aircraft . we have changed the prop and it was ok .the prop i think out of balance Quote Link to comment Share on other sites More sharing options...
nosepicker Posted May 4, 2012 Share Posted May 4, 2012 I have found that the tailpipe vibes that I encounter are high freq. The lord mounts and prop balancing are low freq. I'd throw the chadwick on the RGB/Compressor and do a torquemeter runout. Quote Link to comment Share on other sites More sharing options...
Herc 308 Posted June 1, 2012 Share Posted June 1, 2012 One thing you can try is hooking up the vibration kit and see if the vibs of items are within the limits of the books. you could have something loose in the turbine causing the vibration. Quote Link to comment Share on other sites More sharing options...
Great Above Posted June 1, 2018 Share Posted June 1, 2018 Our C130H also has same problem and we have been battling to solve the problem. It's still there ..... 1 Quote Link to comment Share on other sites More sharing options...
Shola Posted June 28, 2018 Share Posted June 28, 2018 I thought this problem was resolved after we replaced the engine mounts (upper and lower)? Confirm please. Quote Link to comment Share on other sites More sharing options...
Ahmer Posted October 18, 2018 Share Posted October 18, 2018 Plz inspect your turbine for any damaged. (Boroscope inspection) Quote Link to comment Share on other sites More sharing options...
pmostafiz Posted July 24, 2019 Share Posted July 24, 2019 On 5/16/2011 at 12:39 PM, Lkuest said: Was a bit of a joke. I figure if you can't see the outboard motors, and they make it out ok, then tailpipe vibes are a bit of a comfort item to look at. Here's what I got for a vibe. If the vibe is in the tailpipe only, and not in the throttle or condition lever: Check tailpipe for proper installation Inspect front engine mounts (i'd just change them and be done with it. Sometimes the inspection lies.) Inspect rear engine mount (already changed it, right?) Borescope turbine (-15 engines can throw a rotor blade and you wouldn't be able to tell otherwise) If no defects were found, then the tailpipe vibe is within limits, and I dare anyone to try to create a limit with a ruler. If the tailpipe vibe is accompanied with a throttle or condition lever vibe, then this is what I got: Perform a propeller loose blade inspection Perform a propeller blade tracking inspection Inspect prop afterbody, torque retainer assembly, and front spinner for loose or damaged components Check propeller hub nut for proper torque (replace RGB if out of limits) Check prop shaft vertical movement and end-play Check rear engine mount (already changed) Check prop balance If no defects are found, replace propeller These are only recommendations, of course. You can complete them in any order. Checking the wing truss mounts like Ben said couldn't hurt, as well as checking the engine sloping longerons and tie struts as well. You should also look at the maintenance history. If either the engine or propeller have been changed just before the problem started, suspect shipping damage or improper installation of either the engine or propeller or other major structural components. Sometimes, a throttle vibe is normal, and a tailpipe vibe is normal, it's your call. Just pretend like you are going to be flying on the plane and make sure you look at anything that would make you want to land as soon as possible. Yes, I Agree Quote Link to comment Share on other sites More sharing options...
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