Ed Cesnalis Posted November 7, 2012 Report Share Posted November 7, 2012 My CTSW is in South Lake Tahoe where I aborted a take-off yesterday due to partial power loss. I have 5 hours of flying since my rubber hose change. Jeremy is headed for Tahoe today to diagnose and fix. We are expecting rubber debris. Losing power on take-off is a serious issue. Link to comment Share on other sites More sharing options...
Doug G. Posted November 7, 2012 Report Share Posted November 7, 2012 It is starting to look like the hose change is doing more harm than good. Anyone read Mike Busch's article in EAA Sport Aviation this month? Link to comment Share on other sites More sharing options...
kentuckynet Posted November 7, 2012 Report Share Posted November 7, 2012 I only personally know of 3 hose changes and all have had some type of forced landings! I have not changed mine..... Link to comment Share on other sites More sharing options...
Roger Lee Posted November 7, 2012 Report Share Posted November 7, 2012 Here are the three issues with the fuel hose causing people grief. Believe it or not is the mechanics fault. After two carb issues I changed my ways as I listed in the maint. section of the forum and have not had any issues since. First, quit using fuel injection hose and use standard carburation hose. Using fuel injected hose causes mechanical damage because of the fit over the fittings. Second, get rid of most of your cutters. Most sizzors and serated edge cutters especially if they are dull will leave pin head debris you cant see and then breaks off when it is pushed over a fitting. Use something that has a scalpel type knife edge like the picture I post under the maint. Section. It does not leave any little pin head size chunks to break off and float down stream. Third, the fuel hose that is the issue is the one off the bottom of the fuel pump to the fuel distribution block on the carb balance tube. The pump has a small screen filter in it, so your problems manifest after that. When pushing a hose through the fire sleeve blow through it before putting it over the fittings to get rid of any fire sleeve or rubber debris. Do these three things and your troubles will go away. I also now use Gates Barricade standard carburator hose. O'Rielly's Auto parts has it on line and you can pick it up at the store. One last comment, Don't over tighten any Band-It clamp on the fuel hose as these clamps have enough strength to close the hose off. Any time you break open a fuel system the chance of contamination exist. Use good clean practices. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted November 7, 2012 Author Report Share Posted November 7, 2012 Carb bowls: Fuel Sump: Fuel Pump: Link to comment Share on other sites More sharing options...
Flying C Farms Posted November 8, 2012 Report Share Posted November 8, 2012 Looks just like mine did when I aborted this past summer. My right bowl was OK, but the left looked like yours. How did your mech. take the picture of the fuel pump ? Will have to check mine now, even after the flight to Page and back. Link to comment Share on other sites More sharing options...
C ICEY Posted November 8, 2012 Report Share Posted November 8, 2012 Sorry to hear that.... did you tear apart the old hoses to see if they really did need replacement? I'd be interested to hear about their condition. Link to comment Share on other sites More sharing options...
Flying C Farms Posted November 8, 2012 Report Share Posted November 8, 2012 I forgot to tell you, great pics ! I am even more stumped by the fuel pump picture after going out in the hanger and looking at mine. Was that done with a borescope ? I too am interested in the fuel hose that is currently on your A/C. Link to comment Share on other sites More sharing options...
Rogerck Posted November 8, 2012 Report Share Posted November 8, 2012 In addition to the items Roger Lee noted in post #4, my partner and I had carb debris and resulting in flight power loss after the five year hose change. The problem was the new hose actually disolved from the fuel and left rubber debris in the carb. Must have been bad hose chemical composition in the batch we had. We have since changed out fuel hoses to use Gates Barricade, non - fuel injected hose. It has an inner lining formulated to withstand ethanol and other gasoline additives. Check out the Gates website for details. We've checked the carb bowl several times, and after five months its squeaky clean. Roger Kuhn Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted November 8, 2012 Author Report Share Posted November 8, 2012 Sorry to hear that.... did you tear apart the old hoses to see if they really did need replacement? I'd be interested to hear about their condition. I still have them. I'll have another look. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted November 8, 2012 Author Report Share Posted November 8, 2012 I forgot to tell you, great pics ! I am even more stumped by the fuel pump picture after going out in the hanger and looking at mine. Was that done with a borescope ? I too am interested in the fuel hose that is currently on your A/C. Dunno, I wasn't there. My CT is on the Ramp in South Lake Tahoe, not yet air worthy. Link to comment Share on other sites More sharing options...
Doug G. Posted November 8, 2012 Report Share Posted November 8, 2012 This may be applicable given that it seems there have been more problems after hose changes than ha e been caused by deterioration. (It also seems Rotax has not done an adequate job in providing the proper techniques for the change.) http://www.sportaviationonline.org/sportaviation/201211/m1/Page.action?pg=26 I'm glad I am three years away from this - maybe some of the danger will be taken out of it by then. Doug G. Link to comment Share on other sites More sharing options...
Roger Lee Posted November 8, 2012 Report Share Posted November 8, 2012 Hi Doug, If you follow the few simple suggestions I listed above you won't have any issues. There have been I relative few that have had issues compared to the number done. In the beginning I had two little issues and had to be reactive and with 3 little simple changes the issues went away. With the info we have on the board at this time it should be easy for any owner and or mechanic to be proactive and miss the little headaches. Link to comment Share on other sites More sharing options...
Doug G. Posted November 9, 2012 Report Share Posted November 9, 2012 I don't think aborted takeoffs fall into the category of "little headaches" and with all of your experience you admit to getting it wrong in the beginning. The POH does not call for an emergency landing for a loss of water. This leads me to two questions: 1) which is more likely to cause the most danger, changing the hoses, or leaving them on longer than 5 years (as far as I can tell this is an arbitrary number)?, 2) If normal procedures are not working, why hasn't Rotax or FD put out the correct ones? Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted November 9, 2012 Author Report Share Posted November 9, 2012 I don't think aborted takeoffs fall into the category of "little headaches" ... #1 I'm glad I changed my hoses some coolant hoses were showing wear. I'm not glad that I used known defective hose and I think I'm pretty pissed at CPS for selling this hose in their CT hose kit. And double pissed that they advised that the bad hose issue had been resolved. This was in June months after the bad hose issue surfaced. And one more thing Roger says that CPS was advised that it was a bad hose choice that resulted in mechanical damage and debris yet after both issues they sold my mechanic this expensive kit. So is this a big deal? My aborted take off from KTVL was done after a full power run up from a smooth running engine, done at the hold short line. I had an abort point picked out but I quickly established a positive rate of climb and it wasn't an issue until I realized an almost total power loss and my climb became a float that was going to end beyond the fence and in the terrain. I had to dive for the runway, 40 degrees, slip and high speed round out to get in contact and begin breaking. If the clog happened a few seconds later there would have been a totaled CT, a few minutes later and survival would be a big issue. Link to comment Share on other sites More sharing options...
Roger Lee Posted November 9, 2012 Report Share Posted November 9, 2012 Hi Doug, It's only arbitrary because we don't have access to the data they do. I doubt it will ever be published. Many other aircraft in the GA community have hose time limits as do our cars. How many of you in your life have seen a hose failure in an auto, like a coolant hose. You can pull over in a car, but your coming down in an aircraft if you loose a coolant, oil or fuel line. It's more of a, We don't want you to crash verses I have to call AAA now. You should have flown helicopters, I did for 6 years, everything is time limit replacement almost whether it looks good or not because it it fails your on your way down. Those numbers seemed arbitrary to me too, but I new they had data I didn't. Until we know everything an MFG does and all the testing and experience behind it then our guessing is just that, uninformed guessing. Many companies do tell mechanic exactly how to do this, but only what needs to be done and not always how to do it. Doing it is the mechanics a repsonsility. These are written for world wide aircraft and mechanics and they don't all have access to the same things for the work so it can't be that specific or some would not have the same items to accomplish the same task. Here are two very simple examples. One is Rotax uses and recommends certain Loctite products which are only available ink Europe. They do however allow equivalents. Second example is on the constant compression coolant hose clamps. They say to use the special hose clamp pliers to remove these clamps. Do you need them, no, they can be removed with other tools. So companies that are world wide announce a task and its up to the mechanic to how it gets accomplished. That said many people world wide do things the same at times too. Link to comment Share on other sites More sharing options...
Roger Lee Posted November 9, 2012 Report Share Posted November 9, 2012 Hi Ed, Was the hose used fuel injection hose? I had told CPS that I thought Gates Barricade hose was a better all around choice for their fuel hose stock. You may never get the engine to cough on a run up and 95% never do. You are sitting with no movement and very little turbulence in the carb bowl. When you take off you have fuel movement in the bowl and more turbulence to bring debris off the bottom and up into the suction and vortex area around the main jet. This is why most don't experience this until take off. The only savior about these crappy incidents is that it is usually never totally blocked and most times only affects one carb at a time so you experience a power reduction, but never a full blown engine loss. Scary for sure. I have completely lost many an engine in the old two stroke days and a Rotax 912 so I know the feeling. Link to comment Share on other sites More sharing options...
S3flyer Posted November 9, 2012 Report Share Posted November 9, 2012 Interesting. Given the scenario of how a power loss could occur after hose replacement, it sounds like it would be a very good idea to do a couple fast taxi trips down the runway then taxi back to the hangar to check for debris. Link to comment Share on other sites More sharing options...
Roger Lee Posted November 9, 2012 Report Share Posted November 9, 2012 Hi Dave, I'm not sure that would cause the debris to come up off the bottom of the bowl. I think you may need full fuel flow, movement within the bowl from the aircraft pitch and motion, but you never know when that magicable "E" ticket ride moment may happen. I always have my guys do three laps close in the pattern at altitude before they leave at varing throttle settings, but especially full throttle. Link to comment Share on other sites More sharing options...
Doug G. Posted November 9, 2012 Report Share Posted November 9, 2012 How many hose failures had there been by five years? If they caused emergency landings the would be in the NTSB reports. As far as hose failures in autos (outside of racing) I have seen one in my 62 years, and that was actually a fan belt failure that ended up cutting the hose. It is also my impression that LSA requires the spelling out of methods and procedures, if special methods and procedures are needed, which in this case you are saying is true. If Rotax is not a part of the FAA Light Sport investigation, according to what you have said, they ought to be! They are endangering people by having mechanics experiment and owners be test pilots for the "fixes." Link to comment Share on other sites More sharing options...
FastEddieB Posted November 9, 2012 Report Share Posted November 9, 2012 If they caused emergency landings they would be in the NTSB reports. Probably not. Only a small percentage of emergency landing show up in NTSB reports - only those with fatal or serious injury or major damage. Most emergency landings are relatively benign, and really don't show up anywhere. Link to comment Share on other sites More sharing options...
Doug G. Posted November 9, 2012 Report Share Posted November 9, 2012 That doesn't seem to fit the reports that I see in all the magazines. Quite a number of them are minor, or no injuries. (Particularly the NTSB preliminary reports in Flight Safety magazine.) Link to comment Share on other sites More sharing options...
FastEddieB Posted November 9, 2012 Report Share Posted November 9, 2012 Hmmm... Maybe the NTSB gets involved somehow in "incidents" that are not "accidents" - I don't know. This is my reference at to when I think the NTSB needs a report: http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&SID=a1f8bffdf657677cda850b192f8ba0a7&rgn=div8&view=text&node=49:7.1.4.1.12.2.1.1&idno=49 Link to comment Share on other sites More sharing options...
Roger Lee Posted November 9, 2012 Report Share Posted November 9, 2012 I don't think a hose change needs special methods just better and cleaner ones that most mechanics would benefit from. I have seen hose failure with hose less than 5 years, but many beyond that. Ask Jeremy about hose failure and its cost. I believe the 5 years is a very safe estimate and yes they could go longer, but who gets to decide when they have had enough? Hose failures have and will continue to bring aircraft down. If there is no damage on an engine failure landing or partial power loss rarely is the NTSB ever notified. Only if there is enough damage or injury. Some items I truly believe should be on condition because you can actually see them and they are not a flight safety issue and the plane can function even if it fails. If it is a flight safety issue which will cause an emergency landing and possible injury and the inspection is subjective to too much human error or out right cheapness from owners then they should be timed issues and just done. I don't believe in unnecessary maint, but believe in safety and rely on other experts that have more data, experience and testing facts than I have. Yes some things we do could be more on condition, but someone some where had to draw the line in the sand somewhere to try and help people. I just live with it like everyone else and I don't get to make the big decisions. Out of my pay grade. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted November 9, 2012 Author Report Share Posted November 9, 2012 Roger, CPS sells the rubber part replacement kit that I bought and says that it is designed by Roger Lee. It includes the Gates fuel injection hose that you won't even use yourself. Maybe you should tell them to change that or take your name off of it? The part obviously isn't worth the risk, the issues have not been resolved yet they continue to sell it. http://www.cps-parts...?idproduct=1483 Link to comment Share on other sites More sharing options...
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