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Wing Nut

Fuel Pump Vent

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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

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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.

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Teflon fuel hose are only on the brand new engines or if you order a $567 pump with hoses then you have to cut them to make them work for our application which Rotax doesn't want done. Use any good rated fuel hose and if your fuel has ethanol make sure it is rated for ethanol.

 

You should have got fuel hoses unless whom ever you received your kit from didn't want to supply fuel hose any longer. The hoses on your engine with ferrule's need to be cut off just like any other clamp. Cut a longitudinal slot in two places then put a flat tip screwdriver in the slot and spread it open and slide the hose off. 

The coolant hose that comes off the coolant fill tank is an FD installed hose. It is 17MM and has a spring in it so when it bends it doesn't collapse. It's the same 17mm hose as the rest of the engine. There is a spring in the #1 cyl. coolant hose too.

Rotax doesn't supply many hoses and leaves that up to the builder whether they are private or an MFG.

 

"Do they expect you to just cut off the old fuel lines and reattach to the New Fuel Pump?"

 

Yes

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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.

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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?

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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 :P. 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.

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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.

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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.

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" 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."

 

You should drill holes. This was an FD document years ago. Drill a large enough hole in the side of the fuselage to access the clamp, about 3/4".  Be careful drilling in the right side not to hit any plastic tubing along the bottom of this route. I put a putty knife blade down along this side to it will protect any tubing. You can use a Dremel grinding wheel to open the hole too. When you replace the hose and clamp use a fuel injection clamp. I like to replace the screw with an Allen head so next time it is really easy to access and remove. The standard hex head will work.

When I apply new clamps on the fuel hose out on the tank outlet fitting I always open the hole where the hose goes through and into the fuselage up some with a Dremel grinding wheel so the clamps don't get hung up sliding the wings back in place. many times the hole is just small enough for the clamp edges (depending on the clamp used) to get hung up and make pushing the wings back together a pain.

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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.

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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.

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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.

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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

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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?

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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/

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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)

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You may get an oil drip on a hot engine or exhaust. It is normal for this new Corona pump to have drips of oil. Put a vent line on it and do not put it out in the air stream.

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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

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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.

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