mechanic80 Posted August 7, 2010 Share Posted August 7, 2010 A FALSE low propeller oil warning light has caused many shutdowns in air. the culprit was oil level float indicator...Hydraulic used is 5606..and oil level float indicator part no is 519661... do u guys get the same problem with the floats or there is another oil level float being used..please tell any other reliable float(s) that don't make a false warning. Quote Link to comment Share on other sites More sharing options...
mechanic80 Posted August 7, 2010 Author Share Posted August 7, 2010 please give an input....hurry..please Quote Link to comment Share on other sites More sharing options...
Herc 308 Posted August 7, 2010 Share Posted August 7, 2010 Yes we have the same hyd fluid and float switches and we have a shit load of problems with the switch. I wish they had a different one. Darrell Quote Link to comment Share on other sites More sharing options...
tusker Posted August 8, 2010 Share Posted August 8, 2010 ..........................and good day herk308!!.....................John Boy Quote Link to comment Share on other sites More sharing options...
mechanic80 Posted August 8, 2010 Author Share Posted August 8, 2010 any body there Quote Link to comment Share on other sites More sharing options...
Lkuest Posted August 8, 2010 Share Posted August 8, 2010 Those float switches are a craps shoot. Seen some last 20 years, seen others last a month. I've never seen a correlation between part numbers and failures. I just think it is a poor design, and nobody's cried loudly enough to the right people to get a redesign. Might be something to bring up at the next T56 user's conference. I would personally like a quantity indicator to replace a dummy light. That way the engineers can write up the props when they are a quart low every time they land so we don't have to check servicing all the time. Quote Link to comment Share on other sites More sharing options...
Mcmuffin07 Posted August 9, 2010 Share Posted August 9, 2010 We're having the same issue, all the time. We just put out a TAR to change the service check, but i agree with Lkuest, we should have a quantity indicator. I'll ask my AFETS rep, he has alot more time on the ol' Herc than i do. Quote Link to comment Share on other sites More sharing options...
pjvr99 Posted August 21, 2010 Share Posted August 21, 2010 These things have been giving problems for more than 50 years. The P3 props use a pressure switch on the primary pump to give indication Quote Link to comment Share on other sites More sharing options...
mechanic80 Posted August 23, 2010 Author Share Posted August 23, 2010 means.... lets suffer some more Quote Link to comment Share on other sites More sharing options...
Guest Posted September 7, 2010 Share Posted September 7, 2010 man those pressure switches are always going bad, but just like a macaws panel. Its good until it breaks enough and you need to do a tcto that changes some system warning back into the way older-style aircraft have it... Quote Link to comment Share on other sites More sharing options...
trev130eng Posted September 8, 2010 Share Posted September 8, 2010 Any reason why lockheed havn't come up with a fix for this known problem? We have also being asking for years for a permanent fix for the doppler panel. Changing the paneloc fasteners when enough have gone bad takes a long time and keeps the aircraft out of service for a few days. A real pain when the doppler has been removed. Quote Link to comment Share on other sites More sharing options...
NATOPS1 Posted September 10, 2010 Share Posted September 10, 2010 I think they took them off the civilian version. Quote Link to comment Share on other sites More sharing options...
qasimzaheer Posted September 13, 2010 Share Posted September 13, 2010 we are also facing the same problem. initially we were using the switch having the above mentioned part number but later on we started using float valve having different part number_____. i will tell u later on but there serial numbers are starting with MDO. even then the problems are still the same. Quote Link to comment Share on other sites More sharing options...
RRR Posted September 30, 2010 Share Posted September 30, 2010 This issue is an active item and was briefed at the 2010 T56/Propeller Users Conference. Inflight engine shutdowns due to propeller low oil level indications have been an issue for many years. The main causes are normally either incorrect propeller servicing or the propeller oil level indicator / float switch float sticking or shorting out. I truly believe that if you check your oil levels while the hydraulic fluid is hot (within 30 minutes after shutdown) it will minimize the error of improper propeller servicing. If you wait hydraulic fluid bleeds back from the pressurized sump to the atmospheric sump which is why you have to run the auxilary feather motor to scavenge the oil back into the sump to check the oil. For the sticky floats keeping the hydraulic fluid as clean as possible helps. The use of MIL-H-87257 in lieu of MIL-H-83282 is supposed to help. These two fluids are compatible and can be mixed together if necessary. MIL H-5606 has not been used in USAF C130 aircraft since the early 1980's. For the shorting issue the USAF tech order is going to be changed to go back to putting sealing compound in the float switch cavity or using small rubber wire boots to prevent wires from shorting out against each other. In addition, there has been consideration of redesigning the pump housing assembly. The other issue is that an inflight shutdown is not necessary if an aircrew encounters a low propeller oil indication unless there is a visible oil leak or a RPM fluctuation indication. But, we all know how that goes. Hopefully, we will be able to get a handle on this through diligent maintenance, education and of course engineering efforts and redesign. I will not hold my breath on the latter. Quote Link to comment Share on other sites More sharing options...
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