Doug G. Posted December 19, 2012 Report Share Posted December 19, 2012 So, in the end you are saying CPS is, and has been, selling the wrong hose? Although it is always the end user's responsibility, I think there is also a responsibility by the company selling a part to make certain it is fit for the application, and by the mechanic for proper installation. Just because it is the pilot or owner's final responsibility, that does not allow the others to be negligent. Link to comment Share on other sites More sharing options...
Doug G. Posted December 19, 2012 Report Share Posted December 19, 2012 Safety Officer has posted two excellent articles on this issue in the blog area of this forum. They are both well stated and informative. Thank you. Link to comment Share on other sites More sharing options...
Tom Baker Posted December 19, 2012 Report Share Posted December 19, 2012 Tom, Gates fuel injection hose IS the problem if Gates says it should not be used on barbed connectors, and CPS provides it for engines that have barbed connectors, irregardless of what originally came on the engine. Your second point is taken. What is the replacement schedule Cessna recommends for hoses? Doug, I don't have a late model Cessna book here to look at, but I do have a Piper book. It calls to have engine hoses replaced at 1,000 hours. The AD on Piper oil cooler hose says 1,000 hours or 8 years. I think the new maintenance manuals have the 8 year time also. I also remember when I worked on Beech Barons that they had a replacement time also. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted December 19, 2012 Author Report Share Posted December 19, 2012 Hi Ed, Not a single person here is trying to bad rap you. Not trying but succeeding. I am bound by a confidence so I will leave it at that with the exception of the comment/question that when warranty claims are concerned 'what can you do when a customer just won't go away?' Personally I have tens of millions of dollars in warrantied work out there, I'm not a clueless idiot that won't listen to reason. CPS has an evolving defense as do you and your backing them up every step of the way. How about this, I pick 3 issues and you actually respond to them? Your defense of CPS is somewhat repetitious and you do not address my complaints. You live on both sides of the fence - its time to pick a side. You are currently doing a hose change but you will not use the CPS supplied hose that comes in their kit developed for the Flight Design CT. You stopped using it almost 2 years ago in order to reduce the amount of rubber debris that you realized upon fuel line changes yet you continue to defend CPS for selling it after they had removed it from inventory due to an incident that resulted in power loss from rubber debris. You also defend the fuel line itself and continue to endorse the product on CPS's web site. http://www.cps-parts...product=1483 I cannot see how you can continue to defend and endorse this hose while you continue to refuse to use it personally. You need to go full disclosure, if you receive revenue from CPS it colors how readers interpret your representations. Will you continue to reject this hose for safety reasons while defending and endorsing it? Hint: you can in fact control what other people publish on their web site in cases like this Blame the mechanic or blame the waffle texture? My mechanic has been blamed by you for over clamping, you didn't respond when I pointed out that the damage was not caused by clamping. CPS blamed him for not flushing and cutting poorly without any evidence of that, then they changed their minds when I pointed out the damage from the barbs. Now CPS blames my mechanic for causing damage with the barbs and they drop various names of people that have not even looked at the hose or talked to me at all. (Perhaps you can give me Eric Tucker's Email? I have the others.) No one will respond to the waffle texture issue, having raised strands of rubber presented to the barb's cutting edges at a 45 degree angle has to increase the likely hood of rubber debris. The issue is not addressed, all that is done is pointing out that the hose is within specs, therefore it can't be the hose. Well it can be the hose / fitting combination if the amount of waffling is aloud to vary while the hose is within specs. So look at your perfectly smooth Gates Barricade again and compare it to my damaged Gates Barricade that has a waffle texture and comment on which is more likely to shave. Also comment on how much insertion force is too much and how you measure the force? Do you consider conditions, lubrication and inside texture? Can you go from prior successful experience with other Gates hose or do you have to throw that out because this time the hose is from CPS and is waffled? Words mean things - '[D]eveloped by Roger Lee for the Flight Design CT' means certain things by implication. This is how the product that I bought is described, Kevin says this only means that Roger Lee supplied the hose lengths which may or may not be true but it isn't the meaning of the published phrase. A post incident, post investigation interpretation would mean something closer to hoses selected by Roger Lee. Kevin also states, and you defend this, that they have no way of knowing which aircraft their customers fly or work on. #1 I bought a kit designed for a Flight Design CT. and #2 Kevin is denying my claim because the hose is not appropriate for barbed fittings while that is what he sells for a CT and he knows they have barbed fittings. In fact all of our Rotax 912 ULS powered SLSA have barbed fittings, this argument is just one more attempt to point at a reason to deny. No-one replaces the fittings. CPS needs to at least ask if they are stocking and selling hose that is prone to rubber debris. When they removed it from inventory my mechanic had no issue using Gates FI Barricade sourced from NAPA. If the variable is the hose's inner texture, which varies even when within specs and the mechanic is the constant, and common sense says its an issue, and the manufacture does not endorse the fitting type due to rubber debris, shouldn't the issue be addressed instead of simply blaming the mechanic? I can easily damage the CPS waffled hose by inserting a barbed fitting, I cannot easily damage fuel line like the OEM Wurth hose ( it has a smooth substantial inner wall not a waffled, flexible one ) by inserting a barbed fitting. When I look at your photo of your Gates hose with a smooth inner wall I would choose that and reject the waffled hose because of my experience. Perhaps the incident investigation missed the hose / fitting issue because the focus was the hose alone? Link to comment Share on other sites More sharing options...
Jim Posted December 19, 2012 Report Share Posted December 19, 2012 Well said, Ed. Link to comment Share on other sites More sharing options...
Roger Lee Posted December 19, 2012 Report Share Posted December 19, 2012 Hi Ed, I don't think there is anything of value I can offer any more, it's all here in these threads. I'm tapped out on this one. I have given as much info as possible and it should be time to take care of what lies ahead and not let the past consume the future. This was a learning experience for many people and you now have the knowledge to fix the problem on your end. There is enough info in these post that no one should have any problems. You or I can't save the world and each mechanic and owner no matter what plane they do a hose change on or where ever they are in the world will be responsible for getting the right information, parts and installation procedures before they start and don't take it for granted that a hose change is as simple as walking out the door. All my stances to post are in the previous 5 pages. Link to comment Share on other sites More sharing options...
airhound Posted December 20, 2012 Report Share Posted December 20, 2012 Hello, I'm experimental, and when it comes to doing the right thing for engine maintenance I consider hose changing on the same order of the old saying; 'Oil is Cheap' ...regardless of price. Even though I have more lattitude, as an owner operator to accept risk, I believe the SLSA 5 year standard is a good-one for all at risk, regardless of acft category. Although the thread hits-on some difference's of opinion, surrounded by ego, there's definitely a strong community desire for accident prevention and safety in general. Question: Can one assume hose mechanical damage is primarily due to less than sterling hose installation, or can it happen from normal engine operation, over years of engine vibration and temperature changes, working hoses on the fitting barbs? Request: Please, check my following interpretation of this threads information regarding the 5 year hose replacement: Go with the named smooth bore hoses, ensure internal hose cleanliness, skillfully apply/instal the fittings and clampage, and most importantly, as suggested, do a thorough post maintenance run-up and Carb Bowl inspection. Perhaps, do two or three run-ups of sufficient duration and RPM..inspect, then go fly alone on a maintenance check-ride in the pattern or some forgiving area. What did I miss? The only other thing I can add would be to check the bowls more-frequently after hose replacement. Good-discussion, vasilates between; "kind'o-like trying to put edges on a marhmellow...to, if it ain't broke, don't fix it...... Doug Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted December 20, 2012 Author Report Share Posted December 20, 2012 Question: ...Can one assume hose mechanical damage is primarily due to less than sterling hose installation, or can it happen from normal engine operation, over years of engine vibration and temperature changes, working hoses on the fitting barbs?... In my case only the newly installed hose was damaged. The 6 year old OEM hose looked very good on the inside but the hose overall may have stiffened up some. Link to comment Share on other sites More sharing options...
S3flyer Posted December 22, 2012 Report Share Posted December 22, 2012 It would be nice to hear from all the positive experiences out there and the positive reasons for doing this and not just negative comments. Have you noticed the other hundred plus or so positive hose change owners haven't chimed in. Why hasn't any of the owners that don't want to do this procedure brought up any positives about a hose change as it relates to their maint and safety? That would concern me if owners thought there were no positives and only negatives. Some oil on a squeaky wheel from you positive guys would help. I had my 5 year rubber part replacement service done 4.5 flight hours ago by SportAir, the import of the Sting S3/S4. They have done a lot of these for their own fleet and many other LSA's with no issues. Mine was no exception Link to comment Share on other sites More sharing options...
CT4ME Posted December 22, 2012 Report Share Posted December 22, 2012 'Nary a problem here, at least no debris. 'Did have a weepy connection inside the panel area, where the fuel line connected to the valve (or maybe it was the filter). I believe it was a piece of the fuel injection hose that had a hard time getting over the nozzle. 'Never really figured what caused it, but replacing and re-doing fixed it. Tim Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted December 22, 2012 Author Report Share Posted December 22, 2012 I noticed that back in the Spring that Larry 'Flying Bozo' had Gates Fuel Injected Hose that was problematic. His photos clearly show the waffle pattern which can be seen from the outside of the hose as well as from the inside. The waffling here is extreme and it makes it pretty easy to visualize how a perfectly round barb would shave a texture like that smooth. Now compare it to good / proven Gates hose that is smooth inside and out. Gates does not care about this texture for 2 reasons, 1 they do not endorse rubber hose over barbed fittings and 2 they do not endorse aviation applications. As long as the hose performs in terms of pressure and fuel additives Gates is happy with it. We have heard the argument that LSA does not require TSO'd components which is true but its not good argument in this case. My EFIS and auto-pilot are not TSO'd but at least they were intended for Aviation applications and it turns out they work well. My tires and tubes however where wheel barrow quality as opposed to aviation and they didn't work well at all. In fact they were a bad choice and got replaced with something appropriate. The more I research this the more I see that the number of Gates hose failures on 912 5 year changes has been totally unacceptable. Here's a challenge for anyone. Start with a barbed fitting, a Rotax banjo fitting bolt with barbs would be best. Next get some 5/16 Gates Fuel Injection Line that has good evidence of a waffled texuture, equal to the texture in the photo with the barb damage. Now demonstrate if you can install without damage and if you can what did it take. Link to comment Share on other sites More sharing options...
Tom Baker Posted December 22, 2012 Report Share Posted December 22, 2012 The Rotax banjo fittings take 1/4" hose. The barbed fittings that take the 5/16" hose come from Flight Design. The Rotax fittings have a smooth barb, while the brass fittings from FD have a sharp barb. Tom Link to comment Share on other sites More sharing options...
Runtoeat Posted December 23, 2012 Report Share Posted December 23, 2012 Tom, your observation regarding "sharpness" of the barbs is significant between FD and Rotax fittings. In an earlier post, I suggested one might consider slightly "smoothing" the barbed fittings with a file or sandpaper before installing the fuel hose. Experience designing fuel systems tells me multiple low profile barbs adequately retain a clamped hose. Link to comment Share on other sites More sharing options...
Tom Baker Posted December 24, 2012 Report Share Posted December 24, 2012 Just a .02$. I am finishing a hose change, and had a small hose with a bolt in it covering the barbed fitting that goes into the airframe. This airplane is an early CTLS, and I found some things that are quite different from the other airplanes I've seen. Anyway, when the hose is pulled off the barbed fitting you can see a cut in the inside of the hose. It is OEM hose BTW. I have had times where I had a hose over a fitting, and needed to remove it because I had the wrong size clamp or forgot a Band-it for the fire sleeve. When this has happened I always cut the end off the hose if the length would allow, or start over with a new hose. I wonder if someone removed a hose and reinstalled it, if this could have contributed to the hose debree problem. I know that the hose should not be used with a barbed fitting. I can see the damage from the removed hose, but wouldn't the debree be trapped between the fitting and the hose until the hose is removed? Tom Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted December 24, 2012 Author Report Share Posted December 24, 2012 Tom, I was going to post about the danger of pulling on fuel hoses that are already installed on barbed fittings. The hose could be in good shape until pulled and at that point it could cut or shave the lining. If the cause is vibration over time or pulling I think the debris would be caught in between the lining and the fitting unless the 1st barb completely severs the lining. I have seen a case like this long ago and the lining collapsed and accordioned and created a total blockage. Damage upon installation happens with the back side of the barb's cutting edge and pushes the debris into the line as it is installed. Link to comment Share on other sites More sharing options...
Flying Bozo Posted December 25, 2012 Report Share Posted December 25, 2012 Tom, After having the carb debris issue happen to me four (4) times in the air with reduced power I was determined to get to the bottom of the issue of the hose situation. From what I observed on my hose that was replaced the problem was NOT the fault of the barb cutting into the hose. The hose itself was not able to hold up under the fuel that it was supposed to carry. See the attached picture and you can see the barb area and then the non barb area showing how the hose itself was disintegrating. I can't imagine why since it was supposedly fit to be used on fuel injection applications and under this low pressure application it didn't hold up at all. Larry, Flying Bozo Link to comment Share on other sites More sharing options...
Flying Bozo Posted December 25, 2012 Report Share Posted December 25, 2012 OK I tried to post a picture to the previous post I just made and can't find how to do it. Help on this because the picture is very revealing. Larry Flying Obzo Link to comment Share on other sites More sharing options...
Tom Baker Posted December 26, 2012 Report Share Posted December 26, 2012 Larry, I know that all the problems have not been hose fitting related. If I remember correctly you had a problem with the 1/4" hose. This is the same hose that Rotax had a problem with. The hose fitting problem is mostly with the 5/16" hose. Tom Link to comment Share on other sites More sharing options...
Safety Officer Posted December 26, 2012 Report Share Posted December 26, 2012 Here is what a set of float bowls should look like after a hose change. If the rubber hose is installed correctly then this is what they should look like. Install it with poor technique and rubber debris can happen. Hose selection is only a small part, installation is everything. These carbs have run time on them and they are so clean you could dump the fuel and cook soup for lunch in them. :unsure: Link to comment Share on other sites More sharing options...
Flying Bozo Posted December 27, 2012 Report Share Posted December 27, 2012 Here is the picture of the hose that I have been trying to upload. This is the "new" piece that was replaced at the rubber replacement time. You can see it is not the barb that caused the debris but the hose itself was coming apaprt. Larry Link to comment Share on other sites More sharing options...
Doug G. Posted December 27, 2012 Report Share Posted December 27, 2012 Which brand/type of hose is this? Link to comment Share on other sites More sharing options...
Flying Bozo Posted December 27, 2012 Report Share Posted December 27, 2012 It was a Gates fuel injection hose. Larry Link to comment Share on other sites More sharing options...
Safety Officer Posted December 28, 2012 Report Share Posted December 28, 2012 Remos and Rotax Bing carbs picture with their barbed fittings and rubber FI hose. Everyone has barbed fittings and rubber hose. It's an industry standard. Link to comment Share on other sites More sharing options...
Doug G. Posted December 28, 2012 Report Share Posted December 28, 2012 Someone should tell Gates, but if they say, "not for aviation use" they have their butts covered. Link to comment Share on other sites More sharing options...
WmInce Posted December 28, 2012 Report Share Posted December 28, 2012 Someone should tell Gates, but if they say, "not for aviation use" they have their butts covered. How about . . . . "Not For Use With Those Types of Fittings?" Seems like the hoses are fine, but they are getting chewed up by the installation and fittings. Link to comment Share on other sites More sharing options...
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