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MARS

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Everything posted by MARS

  1. The 70 PPM C/C packs installed on the B/E/Super E aircraft are notoriously fickle and usually don’t work worth a damn… The problem may or can be one or a multitude of separate problems. I recommend you try the following: NORMAL CHECKS 1. As stated by kersey9502; check the heat exchanger for leakage using the H/E Leak Check Fitting (in the pre-politically correct USAF referred to as the “donkey-dickâ€). 2. Verify the C/C FCV is opening as required: a. If my Can’t Remember S#*T (CRS) isn’t too bad today; I believe with GTC/Air Cart the FCV should be almost fully open. b. Again, if my CRS isn’t too bad today; during an Engine Run the FCV should modulate to maintain 70 PPM and the position indicator on the side of the FCV should indicate about one-third to one-half open. The valve operation is affected by ambient conditions and bleed air system pressure; therefore the exact position may vary somewhat, depending on operating conditions. c. Also, check the FCV filter and all sensing line connections. 3. Pressurize the aircraft and ensure the C/C pack has no leakage while under pressure (even though you stated “we usually fly the B airplanes from FL100 to FL140†there still is a pressure difference affect on the C/C pack and on occasion leaks will show up under pressure that do not when unpressurized): a. Ensure the AUX Vent Valve and UFH SOV are completely closed with no by-pass or seal leakage. 4. Remove the Turbine Ice Screen and ensure it’s not damaged or clogged. “OUT OF THE BOX†CHECKS 1. Remove the Turbine and check the shaft for fwd to aft endplay. If any endplay is present it will cause the Turbine to “slow-down†by creating excessive friction between the shaft and bearings. This “slow-down†usually occurs before the Turbine can reach its optimal effective RPM and causes low flow and higher output temperature. If endplay is present; replace the Turbine (even if new or overhauled) as I’ve seen endplay cause the problem you’re experiencing numerous times, especially in hot environments such as SEA. 2. Check the Pant Leg Duct Flapper Valve to ensure it opens smoothly and fully. The easiest way to check it is to: a. Drill a small hole in the Duct in the upper wing root area large enough to insert a long welding rod. Insert the welding rod and repeatedly move the Flapper valve through its full range of motion ensuring it opens fully and smoothly. If it’s okay, just seal the hole with fiberglass or epoxy. If it’s not okay, oops out comes the Pant Leg Duct… Sorry if I was a little longwinded and hope this helps, though unfortunately low airflow and insufficient cool temperatures are the nature of the beast when dealing with the older 70 PPM C/C packs, especially in hot environments. Regards
  2. Oh well, maybe my old-age Can’t Remember S#*t (CRS) syndrome is kicking in; my experience is mostly on C-130-series aircraft and my experience on L-100-series aircraft is limited. Though I really thought we had changed the outflow valve and our problem went away... With that in mind: To my knowledge the safety valve operates completely independently of the outflow valve and pressure controller as there are no pneumatic connections between them. So, if outflow valve cracks open as required in-flight with the safety valve “forced” to remain closed and everything else checks good, you might consider the following: Based on the settings you provided in your original posting of: “Outflow valve differential control 14.2 (+0.6, - 0.4)” “Safety valve differential control 14.9 (±0.5)” If your overhaul facility adjusted the outflow valve or pressure controller to the high side cracking pressure of 14.8 Hg and the safety valve to its low side cracking pressure of 14.4 Hg, your safety valve would open first and the outflow valve would never reach the cracking pressure it’s adjusted to open at … Just another option for you to consider. Again, hope it helps.
  3. You’re welcome. Outflow Valves are not interchangeable between Military C-130 and Civilian Registered L-100 aircraft, because of the difference in maximum differential opening settings (among other things). Neither are the Safety Valve and/or Pressure Controller interchangeable. None of the P/N’s you listed are in the -4. The -4 lists the following P/N’s: Safety Valve; 103036-3, Controller 102076-5, 102538-2-1, or 102538-5-1. Once you install the correct P/N Outflow Valve, this problem will be solved. You can verify the cracking pressure of the Outflow Valve during a ground pressurization check with the #2 Test Valve closed and # 1 Test Valve open. Hope this helps you.
  4. Not sure if it’s an issue or the cause of your problem; but if you have a USAF C-130 type (P/N 102150-0 or 3314765-1) outflow valve installed it will stay closed until a maximum differential pressure of 15.18 inches of mercury is reached. The safety valve used by USAF doesn’t open until you reach maximum differential pressure 15.90 inches of mercury. So, if a USAF type outflow valve is installed, it won’t open before your Civil Registered C-130 type safety valve does at 14.9 inches of mercury and could cause the problem you’re having. Just a thought as I’ve seen this type of discrepancy in the past when working on a mixed batch of Military and Civilian type C-130’s and the wrong P/N outflow valve was installed. Hope it helps.
  5. If my “CRS” is not too bad today; all the “B’s” I worked on had a GOX system with cylinders/bottles. T.O. 1C-130B-2-10 was UTILITY SYS, and was the maintenance bible of MA (Mechanical Accessories), troops, though they went to being called ECS, ELEN and who know what today
  6. Check out 1C-130H-2-56JG-00-1 (my copy is circa 1993, so check it out in an updated copy); it authorizes the use of Sealant Tape PTFE (SKYFLEX) in lieu of sealant on the aircraft windows. You have to use Teflon washers with the Sealant Tape, but there is no cure time required. Hope this helps.
  7. Actually, the Turkish Air Force has bought five of them, as is!!! They’re currently being put back into a “flyable” condition…
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