Tom Baker Posted February 12, 2012 Report Share Posted February 12, 2012 What hose are you guys using in this location? Link to comment Share on other sites More sharing options...
Roger Lee Posted February 12, 2012 Report Share Posted February 12, 2012 Hi Mitch, I have seen the pic from Pike. I believe you may have had two separate issues. You had that rubber flake in the fuel assembly and that I believe was a piece of rubber. The stuff in the carb bowl after looking at the floats looks like the floats are degrading and need replacement. I also have another theory on some of the rubber flaking. Most of us use some kind of a serrated type scissors to cut the hose verses a nice straight edge type blade like a razor. The serrated blade does not make a perfect scalpel clean cut, but leaves a very tiny ragged edge. Now slide this over the barbed fitting and those little pin head size flakes break off. This is just a theory, but right now is looking pretty good. I am as of this posting going to a new knife edge type cutter that leaves a perfectly smooth cut edge. I have talked to the hose people and they said the hose is fine for the fuel and ethanol. I have had two pieces of hose soaking in ethanol fuel for 48 hours and shake it hard every time I pass it and there are no flakes or issues. It has to be the cut edge and scraping it off as the hose is pushed on. Even blowing the hose out which would get some things out would not blow any attached pin head sized particles out until you tear them off by pushing the hose over the barb fitting. Just my take on it. Link to comment Share on other sites More sharing options...
round_peg Posted February 12, 2012 Report Share Posted February 12, 2012 I haven't asked Pike what kind of tool he used to cut the hose, but would have guessed a utility knife. Are you are seeing ragged edges in the photo, or deteriorating hose? I certainly agree that air pressure is not going to be of much use in cleaning out the hoses. We've been doing this, even knowing that unless the insides of the hoses and any flakes are completely dry then they are probably going to stick. So other than replacing the floats, we're at a loss as to what we should be doing next. Link to comment Share on other sites More sharing options...
Roger Lee Posted February 12, 2012 Report Share Posted February 12, 2012 Hi Mitch, I talked to Pike yesterday. Just replace the floats and replace that one hose to the fuel assembly. That should take care of your problem. Link to comment Share on other sites More sharing options...
Roger Lee Posted February 12, 2012 Report Share Posted February 12, 2012 Well after soaking a couple pieces of the hose for 48 hours and agitating it regularly I pulled them out. Not a spec of hose on the bottom of the jar. The ends were exposed that usually doesn't happen on a fitting and it had an ever so slight a swell on the very ends, most likely the liquid got to the threads exposed on the ends. The insides were clean as a whistle. I even cut these with my scissors and everything looks perfect. Link to comment Share on other sites More sharing options...
round_peg Posted February 12, 2012 Report Share Posted February 12, 2012 Hi Mitch, I talked to Pike yesterday. Just replace the floats and replace that one hose to the fuel assembly. That should take care of your problem. We're still planning on installing the inline fuel filter along with replacing this line. Any reason not to? Also, do you think we should use a different type of hose, such as the fuel injector type that came with the hose kit from CPS? I'd also like to see a section of this hose after it's removed cut longitudinally and opened up to look for any signs of degradation. That may tell us something if we find it, but not much if we don't. Link to comment Share on other sites More sharing options...
Flying Bozo Posted February 13, 2012 Report Share Posted February 13, 2012 Hi all on the debris in the carb problem. It has been frustrating for me but I think I am finally onto the problem and the maybe the solution. I will try to post a picture here of the hose deterioration that I took this afternoon. Look at the top of the piece of hose and you will see where it was on the barb and tightened with the hose clamp. Then look at the deterioration that was outside the barb fully exposed to the fuel in the fuel line. Those chunks that are pealing off are the same things that I was getting in the fuel system. Further, if you submerse this piece of hose in car gas the whole outside gets mushy and turns the gasoline black from the outside rubber sort of melting. I believe that there is different rubber on the inner part of the hose, or at least there is supposed to be I guess but the little bits of crap that were in my system acted just like that outer rubber in that they melted in a gas soaked paper towel by rubbing them and made it look just like a black felt pen had caused the black spot. My conclusion is that there was a bad bunch of hose that evidently got into use and I would suggest that Roger looks into the stuff that he has in stock. On my CT it appears to be only the hose that he used after the fuel pump going to the spreader tube between the carbs. That was a fuel injection hose made by gates and if anyone wants a picture of that with it's nomenclature I will get it for them. In order to be fair in evaluating hose I bought the exact replacement from the auto parts store and it acted the same way when I submersed it in car gas with ethanol causing the gas to turn black when I agitated the fuel. It was melting the outer rubber on the hose. But the big difference in the piece that I just purchased was that when I cut it open the inner part of the hose was in tact and not flaking off. This hose had the same nomenclature on it as the hose that Roger uses so it appears that the stock that Roger got was for some reason perhaps inferior even though it was exactly the same specs printed on the hose although appears to be a different lot that Roger's. So after those experiences I bought a regular car fuel line hose that was not for injectors (low pressure)and submitted it to the submersing fuel test. No problem with this hose, it did not melt in the auto fuel. Since that is a low pressure line I can't imagine that it needs the high pressure hose spec as is used in an a fuel injection application. Giveme feedback on that issue if anyone can....???? If anyone is interested I will go through the procedure that I used to purge the system totally. As you know there is a recirculation aspect to this installation which makes it almost impossible to tell what is happening where and where the crap is getting into the sustem. (Roger and I still have to discuss the recirculation feature and it's purpose). Later on that one. SO I ungrounded the plane and test flew it today for about 30 minutes. Through every contorted maneuver that I could put it through, most of them at full power, it ran flawlessly. I will not leave the airport for some time to be determined since the last time we thought we had it solved I flew it for 3 hours with not a glitch and then it happened. Hope others have some input on this. One more thing, I inspected the other hoses that were installed at the hose change event and they appeared to be a different type of hose that I believe are not of the same type as the trouble hose. I also did the gasoline test on them by rubbing a rag soaked with gasoline on them after pushing back the fire sleeve and they did not melt on the outside like the one I described above. Keep your fingers crossed. Larry N255CT Link to comment Share on other sites More sharing options...
Flying Bozo Posted February 13, 2012 Report Share Posted February 13, 2012 Hi all rubber hose replacement enthusiasts... After reading what I wrote above I thought I better put a picture of the troubled hose so that you might check yours out. It appears that the only place that this was used was exiting the fuel pump to the carb spreader tube. The one that I bought at the auto parts store today had the exact same numbers on it and the one pictured here. And as I described above I didn't use it but chose a low pressure hose for fuel lines. Larry CTSW 255CT Link to comment Share on other sites More sharing options...
Runtoeat Posted February 13, 2012 Report Share Posted February 13, 2012 Larry, very interesting. My experience with auto fuel hose is that the total hose should be resistant to fuel, not just the inside surface. This should apply to the higher spec fuel injection hose. It should not be affected by fuel as yours is. With all of the Chineese rip offs we have that run from medicine and drywall to dog food, it wouldn't surprise me if there is a bunch of Chineese rip off fuel hose being sold without anyone knowing that it is bogus. I hope this is your problem and you can get back to flying your CT and enjoying it. I'll check my recently replaced hose tomorrow just in case. Link to comment Share on other sites More sharing options...
Flying Bozo Posted February 13, 2012 Report Share Posted February 13, 2012 Dick, Yes I agree that the whole hose should be resistant to gasoline. It wasn't that the hoses were made in China or something like that, Roger's was a Gates stamped on the outside and the one I bought at the auto parts store was also a Gates. I can't imagine that they would put out a hose that would melt on the outside by gasoline when it was made to be used for gasoline. I was going to take a video of it when I threw it into a bucket with about an inch of gasoline in it. After a few swirlings around the gas was black! Then when removed the hose was sticky on the outside. If that had not happened I would have never been suspicious enough to cut into the inside and discover the interior disintegrating like the picture shows. Larry CTSW 255CT Link to comment Share on other sites More sharing options...
Flying Bozo Posted February 13, 2012 Report Share Posted February 13, 2012 Dick, I wondered about the rip offs. Both the hose I bought today and the one that Roger installed had the Gates name on it although the writing on each was slightly different and neither had a Logo just printing. They both exhibited the same melting defect(?) although it was only on the outside melting not the inner rubber. The inside of the one that I bought had a smooth and proper appearance as opposed the the one that was on there since the rubber replacement (see picture). You said you were going to take a look at yours. If you dampen a rag with gasoline and rub it on the outside of the hose after you push back the fire sleeve you will be able to tell right away if you have that hose. Your rag will look like you rubbed a black Sharpie marker on it. As near as I can tell I only had one of those hoses on my CT and it is the one that comes from the fuel pump to the carb spreader tube. All the rest that I tested had a different outward appearance (smooth) and did not melt. Keeping my fingers crossed. Larry Link to comment Share on other sites More sharing options...
Andy Posted February 13, 2012 Report Share Posted February 13, 2012 I just put my airplane down with RJ Mechanical for the service. Here's my cut on this whole thing: http://theandyzone.com/flightblog/ Obviously, the trip home from 1H6 to KLVJ (Tulsa to Houston) is not something I'm looking forward to. The only saving grace seems to be that partial engine failure and not a full power loss...if anything happens..is the more likely scenario. Now, I'm really glad I didn't send the 'chute out for repack, too! (Though an argument could be made that maybe I shoulda') Andy Link to comment Share on other sites More sharing options...
Tom Baker Posted February 13, 2012 Report Share Posted February 13, 2012 Andy, I read your blog, and I'm in the same boat as everyone else. One thing I would like to point out though. The price didn't jump on maitenance, because the requirement has always been there. Your just like the rest of us, we didn't realise it when we bought the airplanes because none of them needed the replacement yet. Link to comment Share on other sites More sharing options...
Andy Posted February 14, 2012 Report Share Posted February 14, 2012 You're right about it always having been there. The first I heard of it was around 2009 after I bought my airplane, but I've found references to the requirement in line manuals going back to 2005 and 2006. So, I'll correct that reference in the blog. While I do a lot of homework before buying an airplane, this requirement got by me. Still the economics I referred to in the blog hold and I'm still going to have to not only consider whether we can keep the airplane. I will avoid a Rotax 912 for use in a personal aircraft unless I'm going for an experimental. If we decide to start renting, then I can make up the difference in the rental rate since most of my competition is using the 912 also. That's all TBD. Link to comment Share on other sites More sharing options...
sandpiper Posted February 14, 2012 Report Share Posted February 14, 2012 Probably most of us missed the 5 year requirement. If the folks selling these planes knew about it they were not disclosing it. That, at least, is my take on it. Link to comment Share on other sites More sharing options...
johnr Posted February 14, 2012 Report Share Posted February 14, 2012 Hi all. I have almost completed the 5 year rubber change as required by Rotax. After advice from Roger I even managed the short fuel hoses to the wings. I started with some reluctance until I had difficulty removing one of the fuel lines. I twisted & pulled the line & it broke at the fitting. Close examination indicated that not only had the rubber become brittle but the cord also showed signs of breaking down. A healthy hose would have stretched & the internal cords should have held it all together. I can stretch a piece of new hose but I cant break it. I am so glad that Rotax insist on the 5 year replacement, I believe they got it right. I once helped in trying to extinguish a fire that was probably started by an oil leak. The pilot thankfully landed safely but we could not save the plane. (He was test flying after the installation of a new oil cooler.) How many auto conversions are using the same type of rubber hoses with no thought of replacement. Dare I suggest that an alert & responsible aviation controlling body would at least be mandating the 5 year replacement of all rubber fuel & oil lines. Its less of a problem if a radiator hose springs a leak. They wont last any longer just because they are fitted to an experimental registered aircraft. John Reay Link to comment Share on other sites More sharing options...
round_peg Posted February 14, 2012 Report Share Posted February 14, 2012 FWIW, we have decided to replace all of the fuel hose, not just the length between the pump and carb assembly. A fuel filter will be added in this line to guard against any debris that might be coming from the pump diaphragm, a condition that our A&P feels he can't completely rule out. The new hose will be tested by soaking a piece in fuel before installation. The floats will also be replaced. Other than that, we can't do much but do the work and test for some hours, and hope it corrects the issue. Link to comment Share on other sites More sharing options...
FredG Posted February 14, 2012 Report Share Posted February 14, 2012 Between hangar and insurance, I spend $4000 per year. If I fly 200 hrs per year, in ten years I get to replace the engine, $20,000 (another $2000 per year). 200 hours at 5 gallons per hour at $3 per mogas gallon is another $3000 per year. So, now I'm up to $9000 per year, without tires, oil, parachute repack, spark plugs, interest on the airplane loan, etc. Is the $400 per year of hose maintenance costs ($2000 every five years) going to dramatically change my operating costs? Nope, looks like less than 5% of my operating costs (perhaps considerably less), depending on the number of hours flown. Yes, flying costs money, but the hoses are a very small fraction of it. Link to comment Share on other sites More sharing options...
CT4ME Posted February 15, 2012 Report Share Posted February 15, 2012 very well said... thanx, FredG Tim Link to comment Share on other sites More sharing options...
round_peg Posted February 18, 2012 Report Share Posted February 18, 2012 We had the fuel lines changed out today and were astonished to find that the 1/4" hose between the fuel pump and the carbs was spalling off flakes of black crud internally. I will post a photo when I figure out how to capture it with a camera, but it is very visible when looking through a short piece of the hose. The 5/16" lines we'd installed at the same time were okay, so those were left in place. The recirculation line was not suffering similarly presumably because it's not subject to the same fuel flow as the other. It was replaced anyway. Contrary to some of the theories, the bad hose was stamped "Made in USA." Link to comment Share on other sites More sharing options...
Flying Bozo Posted February 18, 2012 Report Share Posted February 18, 2012 Hi Mitch, Sounds like the very same thing that I had. Was that hose that was causing the problem a fuel injection hose that had the Gates name on it?? See my earlier post with a picture of the inside of the offending hose. Larry N255CT Link to comment Share on other sites More sharing options...
round_peg Posted February 18, 2012 Report Share Posted February 18, 2012 Hi Mitch, Sounds like the very same thing that I had. Was that hose that was causing the problem a fuel injection hose that had the Gates name on it?? See my earlier post with a picture of the inside of the offending hose. Larry N255CT It's conventional fuel line, with the Gates name stamped on it along with a part number and what appears to be a date or batch number. I can post that info for the good of the order if anyone thinks it might be helpful, but I'm not sure how anyone armed with this info could avoid it altogether. Should Gates be notified, I wonder? Obviously this is an automotive part, and they might be shocked/dismayed to find that it's used on airplane engines. Or would they? Even on a car, this hose might not perform well. Link to comment Share on other sites More sharing options...
Roger Lee Posted February 18, 2012 Report Share Posted February 18, 2012 Hi Mitch, It hasn't really been an issue across the nation so I would just replace yours. Anything else may let those proverbial worms out of the can that you can't put back in. I also think your issue was two problems and not just one. Link to comment Share on other sites More sharing options...
round_peg Posted February 18, 2012 Report Share Posted February 18, 2012 Hi Mitch, It hasn't really been an issue across the nation so I would just replace yours. Anything else may let those proverbial worms out of the can that you can't put back in. I also think your issue was two problems and not just one. I wonder how many people are using the Gates automotive fuel line instead of the hose provided by CPS. Probably not so many. Maybe that's why it hasn't been a nationwide issue? Just guessing. It's replaced. We left the 5/16" lines in place as they did not seem to have the same issue. I flew the airplane uneventfully today. We will continue to check the new fuel filter for signs of debris. Link to comment Share on other sites More sharing options...
westcoastoz Posted February 18, 2012 Report Share Posted February 18, 2012 I used Gates hoses from CPS for my 5 year replacement. Unlike Larry's which was stamped 'Made in the USA'....mine was made in Mexico however have had absolutely no problems since the work was done last June. 1/4" Hose was stamped Gates Corp. Carb.No. C-U-06-002 AW 101210 907Fuel Injection Hose Made in Mexico 5/16" Gates Corp. Multi Fuel Compatibility 4219D SAE 30R9 180psi WP Made in Mexico. Larry may have just got a bad batch. Link to comment Share on other sites More sharing options...
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