Taborsky Posted February 2, 2017 Report Posted February 2, 2017 We have to change the Turbo of our 231 after just 200 hours. Problem you see on the photo- the weel touches the housing! Has anybody had a similar problem or knows what can be the reason? We cool down the turbo 3-5 minutes after each flight- so that can't be the reason. Thanks for helping! 1 Quote
peevee Posted February 2, 2017 Report Posted February 2, 2017 How much play is there? Bad bearing? Quote
DVA Posted February 2, 2017 Report Posted February 2, 2017 At 200 hours, I’d be having a chat with the firm that supplied it, sounds to me like a warranty replacement is at least a possibility. Quote
carusoam Posted February 2, 2017 Report Posted February 2, 2017 (edited) Welcome aboard, Taborsky! Standby for some help with your situation. Thanks for posting such a nicely detailed photo of the challenge you have. Do you have any operations data from your flights? FF, EGTs, TIT and CHTs are often helpful for the discussion. We have a few Turbo pilots around here. Unfortunately, I'm not one of them.... In the meantime, consider using the search function putting in the usual tags might find some interesting details. Contact between the turbine blades and the Turbo's case is possibly going to be related to TIT and new blades with full dimensions. Differential Heating and cooling rates always add to the discussion. There isn't an easy way to know when the contact occurred, during Climb, cruise, descent or after landing... So much oil flows through the Turbo case the temperature of the case is pretty well maintained unless the oil isn't flowing... in this case, have you inspected the oil lines to and from the Turbo? If oil is degrading, it may be blocking flow in these lines.... Private Pilot thoughts with very little experience only. Not a mechanic or Turbo pilot... Best regards, -a- The MS Calvary has already started to arrive while I was typing a hello message... Edited February 2, 2017 by carusoam Quote
Marcopolo Posted February 2, 2017 Report Posted February 2, 2017 Tabor, from the offset of the turbine wheel in the picture it looks like the turbine housing V-clamp was either left loose or not tightened until after the turbo was mounted to the exhaust manifold. If the turbine v-clamp is left loose while the exhaust manifold v-clamp is tightened it could change the alignment of the turbine wheel within the turbine housing. 1 Quote
bonal Posted February 2, 2017 Report Posted February 2, 2017 We have a few Turbo pilots around here. Unfortunately, I'm not one of them.... Hold on there I thought you were one of the displacement guys.. 200 hours seems very short but that could be over many years of non use how old is the turbo? Quote
Zwaustin Posted February 2, 2017 Report Posted February 2, 2017 Didn't get any oil to bearing? Would make sense if shaft is wobbly or you could feel play when pulling on the wheel. How hot has it been run over last 200 hours ? Quote
thinwing Posted February 2, 2017 Report Posted February 2, 2017 It's a bearing failure..the shaft is no longer square to the housing.All the red crap is oxidized metal as the blades rub the housing.Email photo to main turbo Visalia for more professional advice Quote
gsxrpilot Posted February 3, 2017 Report Posted February 3, 2017 6 hours ago, Taborsky said: We cool down the turbo 3-5 minutes after each flight. You actually mean to say you sit and let the engine run for 3 - 5 minutes after each flight thus heating the turbo back up. :-) I'm sure this has nothing to do with the failure of the turbo. But regardless, according to GAMI the turbo is coolest at touchdown and time spent taxiing and idling after only serves to heat it back up again. 2 Quote
thinwing Posted February 3, 2017 Report Posted February 3, 2017 1 hour ago, gsxrpilot said: You actually mean to say you sit and let the engine run for 3 - 5 minutes after each flight thus heating the turbo back up. :-) I'm sure this has nothing to do with the failure of the turbo. But regardless, according to GAMI the turbo is coolest at touchdown and time spent taxiing and idling after only serves to heat it back up again. That is still controversial gsx Quote
carusoam Posted February 3, 2017 Report Posted February 3, 2017 Cooled or heated after touchdown is minimal compared to failure after 200 hours... I do like the idea of sending the photo to a known Turbo shop. Best regards, -a- 1 Quote
MB65E Posted February 3, 2017 Report Posted February 3, 2017 Probably unrelated but the folks at Ram have seen this. A few turbo twin cessnas have gone thru this. Did your boost ever drop off? Did you hear an angry Bee Hive? Was it noticeable at start up? Or only with temp? On some of the Ram turbos, they have had bad metallurgy in the shafts. At certain tempatures the shafts can warp eventually causing failure. This was only evident if the blade rub was detected early. Ram knows it's an issue, they're quiet about it, and absolutely Zero is published. -Matt Quote
chrisk Posted February 3, 2017 Report Posted February 3, 2017 Could be a bearing failure. Or, it could be stretched blades if your TIT was way to high. Send it back to the turbo shop. Quote
jlunseth Posted February 3, 2017 Report Posted February 3, 2017 Doesn't look like stretched blades, the fan is off center in the housing and scraping the housing on one side only. 1 Quote
carusoam Posted February 3, 2017 Report Posted February 3, 2017 (edited) That's where the operations data history file will be very helpful. A high TIT may have occurred or has been occurring without knowing. could be related to bad instrumentation. If there is no JPI or other recording instrument it may be hard to tell the history. Now is a good time to pull the TIT sensor to see the condition of the thermocouple. They live in the harshest environment and have a tendency to burn up over time.... hoping to be helpful with the situation, -a- JL, A history file of usual TITs in the usual range will help point a finger towards the probable cause? Edited February 3, 2017 by carusoam Quote
N201MKTurbo Posted February 3, 2017 Report Posted February 3, 2017 If you try to move the shaft sideways does it have any play? It shouldn't. I'm siding with the housing misaligned theory. Quote
N201MKTurbo Posted February 3, 2017 Report Posted February 3, 2017 By the rule of 600s the repair will cost $1800. $600 for a new housing $600 for a wheel $600 for labor Quote
N201MKTurbo Posted February 3, 2017 Report Posted February 3, 2017 BTW, I can tell you from experience this is not the type of damage that is done by overheating the turbo. 2 Quote
wpbarnar Posted February 3, 2017 Report Posted February 3, 2017 I recently experienced a turbo failure when the gasket between the bearing section and turbine housing disintegrated or broke down. This made the connection between the bearing section and exhaust or turbine housing not rigid. The compressor and bearing section would move relative to the exhaust section resulting in turbine blade rub. The failure was gradual. Thought I had a sticking waste gate. Pulled the cowling off to investigate and found I could wiggle the compressor section and the exhaust section would not move. 650 hrs since new but 19 calendar years old. Mine required the rule of 700s to repair. Bill Quote
N201MKTurbo Posted February 3, 2017 Report Posted February 3, 2017 9 minutes ago, wpbarnar said: Mine required the rule of 700s to repair. Damn inflation! Quote
Jim F Posted February 4, 2017 Report Posted February 4, 2017 There are two check valves in the turbo lubrication system. One on the pressure line and one on the sacvange line. The flow arrow needs to point toward the turbo for the pressures line and away from the turbo for the scavenge line. I have seen damage check valves that block or partly block oil flow. I would agree it was most likely alignment but you need to look at all possibilities. Jim Quote
Mcstealth Posted February 4, 2017 Report Posted February 4, 2017 On 2/2/2017 at 1:45 PM, Taborsky said: We have to change the Turbo of our 231 after just 200 hours. Problem you see on the photo- the weel touches the housing! Has anybody had a similar problem or knows what can be the reason? We cool down the turbo 3-5 minutes after each flight- so that can't be the reason. Thanks for helping! Welcome to the forum. Thanks for letting us look at your issues. Please keep us posted on your progress Is there back and fourth play? Side to side? It seems to me that blade stretch would have a different wear pattern. good luck. Mcstealth. Quote
jlunseth Posted February 4, 2017 Report Posted February 4, 2017 18 hours ago, N201MKTurbo said: By the rule of 600s the repair will cost $1800. $600 for a new housing $600 for a wheel $600 for labor That's for cars and maybe houses. For aircraft, you take the total and multiply by 2 for the regulatory effect. Acutally, I think it is going to require a new turbo and that is in that range of $3600. Quote
N201MKTurbo Posted February 5, 2017 Report Posted February 5, 2017 14 hours ago, jlunseth said: That's for cars and maybe houses. For aircraft, you take the total and multiply by 2 for the regulatory effect. Acutally, I think it is going to require a new turbo and that is in that range of $3600. Why would you buy a new turbo? It doesn't buy you anything more than an overhaul except you buy parts you don't need. Quote
jlunseth Posted February 8, 2017 Report Posted February 8, 2017 (edited) Well, i replaced my turbo a few years ago, about 2009-10. It was rebuilt, not new, but installed my recollection is 3,500. I didn't go back and look it up. PS the core was not worth anything as i recall. It was cracked through both decks. Edited February 9, 2017 by jlunseth 1 Quote
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