Wing Nut Posted February 16, 2014 Report Posted February 16, 2014 I am just in the process of installing the Rotax 5 year rubber kit on my CTsw and am a little disappointed that the thousand dollar kit doesn't include quite a few essential pieces- especially the FUEL LINES as well as the end hoses form the two alluminium pipes connecting the radiator or the sharp bend on the rear of the spider . I know that Rotax would say the Radiator mounting is a FD issue but the rear hose on the spider has to be a ROTAX design. Do they expect you to just cut off the old fuel lines and reattach to the New Fuel Pump? Where has everybody chosen to run the fuel filter vent line so as not to be in a high or low pressure area yet still allow safe ventilation ? Pete
Anticept Posted February 16, 2014 Report Posted February 16, 2014 Did you get a CT specific hose kit, or just a generic one? As for the airframe hoses, that's an FD requirement. They just went along with rotax because of, ya know, lawyers. I have extra engine hose that i need to get rid of (bought for CTLS while we were getting a new engine, new engine came with hoses). I just need to know what you want. Also, if your fuel lines are Teflon, this is no longer required to be replaced per the latest service instruction by rotax, only on condition.
BMcCand - N248CT Posted February 19, 2014 Report Posted February 19, 2014 Wing Nut, Take a look at SI-912-022, the red teflon fuel hose 874-911 from the center out to the carbs no longer needs to be replaced. I'm on my second new style fuel pump, so I just unscrewed the hose nipples, and put them on the new pump 893-110 with crush washers 250-425. If you have the older domed gold pump, the instructions in the kit say to cut hoses. I bought the fuselage fuel tubing from FD, the set in the kit from CPS just didn't fit. It was hi-pressure non-flexible tubing and didn't go over the nipples to the gascolator. I went to an FD service center to get the fuel tubing replaced at the wing root, per LOA 090210. I wasn't comfortable drilling holes in the airplane, and it was tricky to reach in the hole and grind off the old clamp. NOT designed for service. The FD service center also replaced the rubber engine mounts. I wasn't trained on the way you can just rotate the engine to the right rather than undoing all the connections to the airframe. It is much easier to replace the coolant hoses to the water pump with engine rotated. Otherwise you must be a contortionist with a remote clamp tool. It is good Roger mentioned the springs in the coolant hoses, I almost missed that. I ran the fuel pump vent line down the right side of the engine, and down the right engine mount. It is then near where the battery positive wire pokes one.
Runtoeat Posted February 20, 2014 Report Posted February 20, 2014 Bill. Not sure what you mean by "rotating engine to the right"? Is the engine disconnected from the engine mount at the 4 bolts and rotated, leaving the engine mount with it's 6 bolts still attached to the firewall?
Anticept Posted February 20, 2014 Report Posted February 20, 2014 Wing Nut, Take a look at SI-912-022, the red teflon fuel hose 874-911 from the center out to the carbs no longer needs to be replaced. I'm on my second new style fuel pump, so I just unscrewed the hose nipples, and put them on the new pump 893-110 with crush washers 250-425. If you have the older domed gold pump, the instructions in the kit say to cut hoses. I bought the fuselage fuel tubing from FD, the set in the kit from CPS just didn't fit. It was hi-pressure non-flexible tubing and didn't go over the nipples to the gascolator. I went to an FD service center to get the fuel tubing replaced at the wing root, per LOA 090210. I wasn't comfortable drilling holes in the airplane, and it was tricky to reach in the hole and grind off the old clamp. NOT designed for service. The FD service center also replaced the rubber engine mounts. I wasn't trained on the way you can just rotate the engine to the right rather than undoing all the connections to the airframe. It is much easier to replace the coolant hoses to the water pump with engine rotated. Otherwise you must be a contortionist with a remote clamp tool. It is good Roger mentioned the springs in the coolant hoses, I almost missed that. I ran the fuel pump vent line down the right side of the engine, and down the right engine mount. It is then near where the battery positive wire pokes one. Usually you take the wings off a little bit to get to the band-it clamp on the wing root . Much much easier that way! As for "rotating the engine", what that means is you support the tail, undo all of the bolts to the airframe, and it will give you a few inches to pull the engine and mount away from the airframe, and turn it to the right (from the pilot perspective) so you can to the stuff behind it. Most of the airframe stuff attaches to the right side of the firewall (from pilot perspective) so that's why it is easy to do it this way.
BMcCand - N248CT Posted February 20, 2014 Report Posted February 20, 2014 Hello again. Thanks anticept about rotating the engine. The left side tubing, tanks, and carb cables were released. Heater box released. The oil and water tanks were attached to the engine. The 6 bolts on the big frame are removed, and the engine pivoted right, leaving the wiring in place. Maybe I should have said rotated in the yaw axis ! For the fuel tubing, the wings had been removed. The screw clamp on one end of the fuel tubing is easy . The band-it on the top of the metal tube in the A frame was inaccessible. I'm impressed anyone could take that off without drilling holes. For the fuel gauge (clear) tubing, pulling the wings a few inches works great. One can do wing inspection at the same time.
Anticept Posted February 20, 2014 Report Posted February 20, 2014 They put a band-it in the airframe? Just replace it with a spring or screw clamp. The CTLS puts the band it on the wing root. I modified the airframe a little on mine with permission from FD to make both ends the screw clamps.
Tom Baker Posted February 20, 2014 Report Posted February 20, 2014 On the LS the hose is attached to the wing, and the screw clamp is on the airframe side. For the SW it is the other way around. I have changed several on CTSW's without drilling the hole, and can likely do it quicker than getting the drill out. I will say the first one took a little figuring, and was done before I know about the hole drilling deal.
Tom Baker Posted February 20, 2014 Report Posted February 20, 2014 I just did the wing root hoses on one the other day, because the people who did the 5 year didn't replace them. I already had the wings off, and only spent about 5 minutes a side to remove the old hoses and install the new. It will be less the next time because of the screw type clamp that replaced the Oetiker. It is not really a big deal to change it without drilling the hole.
Tom Baker Posted February 20, 2014 Report Posted February 20, 2014 The CTLS is easy, it already has a hole drilled behind the fuel level sticker. The SW needs have access setup for the clamp. I was talking about a SW. I can do the SW through the big hole that is already in the wing root. I agree the LS is different. For the LS the hose stays attached to the wing when it is removed.
Tom Baker Posted February 20, 2014 Report Posted February 20, 2014 I drill a hole for all SW's. And I don't. I have never had to because of the way I do it. For me my way works just fine.
Jacques Posted February 21, 2014 Report Posted February 21, 2014 And I don't. I have never had to because of the way I do it. For me my way works just fine. Tom.. I would really like to know how you do it thanks
Anticept Posted February 21, 2014 Report Posted February 21, 2014 Me too. sometimes you can force the hose and clamp off, but how would you put a new clamp on. I have a tiny wrench with a ratcheting head. Maybe that's how?
Tom Baker Posted February 22, 2014 Report Posted February 22, 2014 Ok, here goes. with the wings removed for inspection I use a series of picks and screw drivers to open the Oetiker clamp. With the clamp opened I slide the hose off, clamp and all. I measure and cut a new hose. I place a screw type fuel injection clamp on the hose so it is tight enough that it doesn't rotate, but not so tight the hose won't slide on the tube. I slide the hose on the tube, and use a mirror to make sure it goes on all the way. I then tighten the clamp with a twist handle rachet and appropriate bit/ socket for the screw. I normally lay a small flashlight inside the wingroot to make it easier to see everything. this rachet is 3/8 drive, but it should work. http://toolguyd.com/kobalt-double-drive-ratchet/
cdarza Posted March 22, 2016 Report Posted March 22, 2016 What would we expect to happen if the fuel vent line is left without a fuel vent line? (no line/hose attached to the vent)
cdarza Posted March 22, 2016 Report Posted March 22, 2016 You may get fuel dripping on a hot engine or exhaust. It is normal for this new Corona pump to have drips of fuel and if you had a big enough pump failure could be more. Put a vent line on it and do not put it out in the air stream. Yikes - Noted - Will do
FlyingMonkey Posted March 23, 2016 Report Posted March 23, 2016 Fuel that hits a hot engine will just evaporate off instantly. It needs a spark or flame to ignite.
N456TS Posted March 23, 2016 Report Posted March 23, 2016 If your pump is leaking fuel, it's in a failed state - brand new or old. The ignition temperature of gasoline is about 495° F. Your exhaust will make a fine ignition source.
FlyingMonkey Posted March 23, 2016 Report Posted March 23, 2016 If your pump is leaking fuel, it's in a failed state - brand new or old. The ignition temperature of gasoline is about 495° F. Your exhaust will make a fine ignition source. True, but gasoline begins to vaporize at 89°F. A drop will flash off to vapor before it ever has a chance to ignite. You'd have to dump more gas onto the exhaust than could quickly evaporate. If this were not the case, you'd have a lot of CT engine fires, since the carbs are directly over the exhaust. That drip tray won't catch everything. I flew the 1400nm back from Arizona with both carb float bowls leaking a bit (they probably leaked on the way out, too), and never turned into a fireball or saw any evidence of combustion under the cowl.
FlyingMonkey Posted March 23, 2016 Report Posted March 23, 2016 I looked it up, the site I read said it starts at 89 and goes up faster from there. Even if wrong a bit, the principle stands.
FlyingMonkey Posted March 25, 2016 Report Posted March 25, 2016 Andy, Here is gasoline MSDS sheet. The vaporization starting point for gasoline is -45F. Gas won't burn below this point as it does not produce any vapor. You must have vapors for gas to burn. Anything above that and gas will produce a vapor and can burn. So at your 89F gas is extremely flammable. Vapor concentration needs to be between 1.4% and 7.6%. Below 1.4% it is too lean a mixture to burn and above 7.6% it is too rich and needs more oxygen. In almost all places in the US and almost anytime of year gasoline will be ignitable because most places aren't below -45F. http://www.archgh.org/default/RiskMgmt/MSDS-Gasoline.pdf To the point of my post...do you think a drip of gas on to the exhaust of a running engine would ignite?
Doug G. Posted March 25, 2016 Report Posted March 25, 2016 That would depend on the flash point, you can boil gasoline as long as you have no spark to ignite it. (Not recommend, however.)
FlyingMonkey Posted March 25, 2016 Report Posted March 25, 2016 That would depend on the flash point, you can boil gasoline as long as you have no spark to ignite it. (Not recommend, however.) That was my point, but the claim was stated that at some temp between 480° and 550° the fuel would ignite without flame or spark.
Anticept Posted March 25, 2016 Report Posted March 25, 2016 The autoignition point is 536F. The flash point is -45F. The exhausts are much hotter than either. Using my heat gun, I was clocking over 800 degrees at higher power settings... and that's with cowling off. Most definitely enough to ignite.
Doug G. Posted March 26, 2016 Report Posted March 26, 2016 Yeah, can't say I am fond of any fluids leading under my cowl. I would much prefer Dex to fuel or oil though.
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