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johnd(at)data-tech.com
Guest

Posted: Fri Mar 07, 2008 11:17 am Post subject: Fuel System Questions

Hi All,



I'm getting ready to order the 3003 aluminum tube for my fuel system in 

the fuselage and have a question. I'm planning to leave the 1/4" ID 

zenith supplied fuel line in the wings and then have an adapter at the 

wing root to the aluminum tubing in the fuse.



I was planning to order 1/4" tubing but it seems  like several folks 

have gone with the 3/8" tubing. Why go with the 3/8" instead of the 1/4" 

? Is it the thicker wall size of the tubing ?

If I go with the 3/8" al tubing then what have folks done for the 

connection to the rubber tubing as I can only find AN807 fittings that 

go from 1/4" hose to -4 or 3/8" hose to -6 size fittings it seems like I 

would need the -6 fittings but with a 1/4" ID hose fitting and I don't 

see those listed at aircraft spruce or wicks ?

Thanks,

John Davis

Burnsville, NC

601XL - Jab 3300

dougsnash(at)yahoo.com
Guest

Posted: Fri Mar 07, 2008 12:11 pm Post subject: Fuel System Questions

John, I am kind of in a similar spot as you.  I am

going to go with the 3/8 line right from the tanks to

the front of the firewall.  At this point I need to

switch over to 1/4 hose to go to the Piersburg pump on

my 80 hp Rotax.  



So far all I have been able to come up with is a

double male flared fitting to adapt hard pipe down

from 3/8 to 1/4.  I might have to use a small section

of hard pipe on the front side of the firewall and

then switch over to flex line.  This is not ideal.



Anyone have any better suggestions?



Doug MacDonald

CH-701 Scratch Builder

NW Ontario, Canada

Skinning Wings



Do Not Archive



--- John Davis <johnd(at)data-tech.com> wrote:



 	  Quote: 	
		   

 <johnd(at)data-tech.com>

 

 Hi All,

 

 I'm getting ready to order the 3003 aluminum tube

 for my fuel system in 

 the fuselage and have a question. I'm planning to

 leave the 1/4" ID 

 zenith supplied fuel line in the wings and then have

 an adapter at the 

 wing root to the aluminum tubing in the fuse.

 

 I was planning to order 1/4" tubing but it seems 

 like several folks 

 have gone with the 3/8" tubing. Why go with the 3/8"

 instead of the 1/4" 

 ? Is it the thicker wall size of the tubing ?

 

 

 If I go with the 3/8" al tubing then what have folks

 done for the 

 connection to the rubber tubing as I can only find

 AN807 fittings that 

 go from 1/4" hose to -4 or 3/8" hose to -6 size

 fittings it seems like I 

 would need the -6 fittings but with a 1/4" ID hose

 fitting and I don't 

 see those listed at aircraft spruce or wicks ?

 

 

 Thanks,

 John Davis

 Burnsville, NC

 601XL - Jab 3300


	


Be a better friend, newshound, and 

know-it-all with Yahoo! Mobile.  Try it now.  http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

johnd(at)data-tech.com
Guest

Posted: Fri Mar 07, 2008 12:27 pm Post subject: Fuel System Questions

Hi Doug,

 

 So why are you going with 3/8" from the tanks instead of 1/4" ?

 

 Thanks,

 John

 

 MacDonald Doug wrote: [quote]    	  Quote: 	
		  --> Zenith-List message posted by: MacDonald Doug <dougsnash(at)yahoo.com> (dougsnash(at)yahoo.com)



John, I am kind of in a similar spot as you.  I am

going to go with the 3/8 line right from the tanks to

the front of the firewall.  At this point I need to

switch over to 1/4 hose to go to the Piersburg pump on

my 80 hp Rotax.  



So far all I have been able to come up with is a

double male flared fitting to adapt hard pipe down

from 3/8 to 1/4.  I might have to use a small section

of hard pipe on the front side of the firewall and

then switch over to flex line.  This is not ideal.



Anyone have any better suggestions?



Doug MacDonald

CH-701 Scratch Builder

NW Ontario, Canada

Skinning Wings



Do Not Archive



--- John Davis <johnd(at)data-tech.com> (johnd(at)data-tech.com) wrote:



        	  Quote: 	
		  --> Zenith-List message posted by: John Davis

<johnd(at)data-tech.com> (johnd(at)data-tech.com)



Hi All,



I'm getting ready to order the 3003 aluminum tube

for my fuel system in 

the fuselage and have a question. I'm planning to

leave the 1/4" ID 

zenith supplied fuel line in the wings and then have

an adapter at the 

wing root to the aluminum tubing in the fuse.



I was planning to order 1/4" tubing but it seems 

like several folks 

have gone with the 3/8" tubing. Why go with the 3/8"

instead of the 1/4" 

? Is it the thicker wall size of the tubing ?

If I go with the 3/8" al tubing then what have folks

done for the 

connection to the rubber tubing as I can only find

AN807 fittings that 

go from 1/4" hose to -4 or 3/8" hose to -6 size

fittings it seems like I 

would need the -6 fittings but with a 1/4" ID hose

fitting and I don't 

see those listed at aircraft spruce or wicks ?

Thanks,

John Davis

Burnsville, NC

601XL - Jab 3300

    	
   

Be a better friend, newshound, and 

know-it-all with Yahoo! Mobile.  Try it now.  http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ 



  	
 [b]

Terry Phillips

Joined: 11 Jan 2006
Posts: 346
Location: Corvallis, MT

Posted: Fri Mar 07, 2008 3:04 pm Post subject: Fuel System Questions

Doug and John

 I have been worrying this same item for the past couple of weeks. 

 I decided that I liked Joe Motis' suggestion (on ch601.org) of putting the electric boost pump(s) in the wing(s), so I started working on that. The nose ribs are different in my wing than in Joe's, so I had to redo the pump channel. I had a few false starts before I came to a satisfactory solution. Then I had to ponder the fuel lines. I wanted to use aluminum from the pump to the firewall, but I couldn't see an efficient way to disconnect the fuel line at the wing root in the event I needed to remove a wing. I considered a rubber hose for the segment from the pump to the wing root. But I have decided, instead, to make a ~2"x3" cutout in the fuselage wall with a cover plate attached by screws and nut plates. Then, I'll put an AN833-6D 3/8" tube x tube bulkhead ell through the cover plate. That way, I can break the fuel line inside the fuselage and, by removing the screws to the nutplates from the fuselage side, I can disconnect the fuel line and the wing from the fuselage.

 I was discussing this all with Clayton, my EAA technical counselor, and he suggested that I also put the gascolator inside the wing. That is apparently what he did with at least one of his RVs. I liked the idea. I have never liked Zenith's design of the gascolator sticking out the bottom of the fuselage. Back to the drawing board. There were significant problems in designing a system that was maintainable. I've gone through my design process in fair detail on my Kitlog Pro website (see URL below). Check out the entries for the past week or two that relate to the fuel system. 

 Meanwhile, back to the tube diameter question. Bingelis' in Firewall Forward, p. 146, says, "Fuel lines -- 3/8-inch x 0.035-inch for aircraft engines (normally)."  That was good enough for me. Also, my tech counselor asked me the horsepower of my engine. I said 120 Hp. He said 3/8" aluminum. I didn't ask why, since that was what I had already planned on--based on Bingelis' book. Did I mention that, in addition to being a pilot and RV builder, Clayton is an A&P, retired after a long career with the MT National Guard.

 When you get to the firewall all you need is a 3/8" tube x 1/4" or 1/8" NPT bulkhead ell. Then screw a 1/4" or 1/8" NPT x hose adapter into that and attach the hose and fire barrier.

 Clayton was also worried about how I would implement the tank select valve and pump power switch. My thought is, first of all, to have a pump and gascolator in each wing. Then I plan to put a single pole-double throw-center off switch immediately above the valve handle. So, valve left, left tank. Switch left, left boost pump. And vice versa. And center for all off.

 I just ordered all the fittings, etc., from Wicks, with the exception of the extra  gascolator. I'll get that from Zenith. 

 All this plumbing is not cheap. Think 200 or 300 bucks. Is the peace of mind worth the bucks and the extra 2 lbs of fuel system hardware? That's obviously an individual decision. I suspect most 601 builders would judge me crazy. But at least my tech counselor liked my direction. And, if it all works OK, I'll be happy.

 Terry

 At 12:09 PM 3/7/2008 -0800, you wrote:

  	  Quote: 	
		  --> Zenith-List message posted by: MacDonald Doug <dougsnash(at)yahoo.com>

 John, I am kind of in a similar spot as you.  I am

 going to go with the 3/8 line right from the tanks to

 the front of the firewall.  At this point I need to

 switch over to 1/4 hose to go to the Piersburg pump on

 my 80 hp Rotax.  

 So far all I have been able to come up with is a

 double male flared fitting to adapt hard pipe down

 from 3/8 to 1/4.  I might have to use a small section

 of hard pipe on the front side of the firewall and

 then switch over to flex line.  This is not ideal.

 Anyone have any better suggestions?

 Doug MacDonald

 CH-701 Scratch Builder

 NW Ontario, Canada

 Skinning Wings

 Do Not Archive

 --- John Davis <johnd(at)data-tech.com> wrote:

 > --> Zenith-List message posted by: John Davis

 > <johnd(at)data-tech.com>

 > 

 > Hi All,

 > 

 > I'm getting ready to order the 3003 aluminum tube

 > for my fuel system in 

 > the fuselage and have a question. I'm planning to

 > leave the 1/4" ID 

 > zenith supplied fuel line in the wings and then have

 > an adapter at the 

 > wing root to the aluminum tubing in the fuse.

 > 

 > I was planning to order 1/4" tubing but it seems 

 > like several folks 

 > have gone with the 3/8" tubing. Why go with the 3/8"

 > instead of the 1/4" 

 > ? Is it the thicker wall size of the tubing ?

 > 

 > 

 > If I go with the 3/8" al tubing then what have folks

 > done for the 

 > connection to the rubber tubing as I can only find

 > AN807 fittings that 

 > go from 1/4" hose to -4 or 3/8" hose to -6 size

 > fittings it seems like I 

 > would need the -6 fittings but with a 1/4" ID hose

 > fitting and I don't 

 > see those listed at aircraft spruce or wicks ?

 > 

 > 

 > Thanks,

 > John Davis

 > Burnsville, NC

 > 601XL - Jab 3300

 Be a better friend, newshound, and 

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 Terry Phillips

 ttp44~at~rkymtn.net

 Corvallis MT

 601XL/Jab 3300 s .. l .. o .. o .. w build kit - Tail, flaps, & ailerons are done; working on the wings

 http://www.mykitlog.com/N47TP/     [quote][b]

_________________
Terry Phillips
Corvallis, MT
ttp44<at>rkymtn.net
Zenith 601XL/Jab 3300 slow build kit - Tail feathers done; working on the wings.

macleod(at)eagle.ca
Guest

Posted: Fri Mar 07, 2008 6:18 pm Post subject: Fuel System Questions

John:



Like you I am going to use the 1/4" line from the tanks to the fuselage

then go with 3/8" Al inside the cabin, and after the gascolator, which is

mounted in the engine compartment (on the firewall), go with 3/8" tubing

to the Rotax fuel pump.



My reasons for 3/8" are:



1. reduced (significantly) friction losses in the line which means lower

pressure drop from the tank to the pump so less chance of vapor lock



2. 3/8" is much stiffer then 1/4" so a more robust system



3. My last kit (Ultravia Pelican PL) used 3/8" from tank to engine (same

engine) and it just seems like a good idea to me to do the same on the XL.



I am using Swagelok Al fittings for all connections.  We used Swagelok

fittings exclusively at the Nuclear Plant where I worked (good

reputation).



The Swagelok fittings come in any size combinations youn can imagine

including from 1/4 inch rubber to 3/8" Al.  You can Google Swagelok to get

your nearest distributor.



Mike

XL - I think my Rotax FWFwd is ready to be picked up

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bryanmmartin

Joined: 10 Jan 2006
Posts: 1018

Posted: Fri Mar 07, 2008 8:11 pm Post subject: Fuel System Questions

3003 tubing is sized by its outside diameter. I would not go with  

anything less than 1/4" ID for any fuel supply lines. That means the  

smallest 3003 line I would use is 3/8" OD tubing. The smaller the  

tubing, the more restriction to flow and the more risk of vapor lock.  

I used 3/8" aluminum tubing from the wing tanks to my fuel valves,  

which had 1/4" female NPT ports using an AN 816-6D fitting. I did not  

like the idea of needing to replace the rubber lines inside the wing  

at some future date. The fuel line is one continuous piece from the  

tank to the valve and passes through a grommet in the fuselage wall. I  

used the rubber fuel lines from my fuel valves to the engine, these  

lines are easier to access for replacement.

 	  Quote: 	
		  

 



 Hi All,



 I'm getting ready to order the 3003 aluminum tube for my fuel system  

 in the fuselage and have a question. I'm planning to leave the 1/4"  

 ID zenith supplied fuel line in the wings and then have an adapter  

 at the wing root to the aluminum tubing in the fuse.



 I was planning to order 1/4" tubing but it seems  like several folks  

 have gone with the 3/8" tubing. Why go with the 3/8" instead of the  

 1/4" ? Is it the thicker wall size of the tubing ?

 If I go with the 3/8" al tubing then what have folks done for the  

 connection to the rubber tubing as I can only find AN807 fittings  

 that go from 1/4" hose to -4 or 3/8" hose to -6 size fittings it  

 seems like I would need the -6 fittings but with a 1/4" ID hose  

 fitting and I don't see those listed at aircraft spruce or wicks ?


	




-- 

Bryan Martin

N61BM, CH 601 XL,

RAM Subaru, Stratus redrive.

do not archive.

_________________
--
Bryan Martin
N61BM, CH 601 XL, Stratus Subaru.
do not archive.

dougsnash(at)yahoo.com
Guest

Posted: Sat Mar 08, 2008 6:02 am Post subject: Fuel System Questions

Because I'm in Canada and that is what is mandated. 

 	  Quote: 	
		  From what I understand, the MD-RA (similar to DAR)

doesn't like any 1/4 inch in the fuel system at all. 
	


Problem is, the Rotax has 1/4 inch fittings on the

pump and carbs.



Doug MacDonald

Do not archive



--- John Davis <johnd(at)data-tech.com> wrote:



 	  Quote: 	
		   Hi Doug,

 

 So why are you going with 3/8" from the tanks

 instead of 1/4" ?

 

 Thanks,

 John

 


	


Never miss a thing.  Make Yahoo your home page. 

http://www.yahoo.com/r/hs

Terry Phillips

Joined: 11 Jan 2006
Posts: 346
Location: Corvallis, MT

Posted: Sat Mar 08, 2008 8:26 am Post subject: Fuel System Questions

Doug



Are the 1/4" fittings on the pump and carb 1/4" NPT or are they 1/4" AN 

tubing fittings?



If they are NPT fittings (like on the Facet 40105 pumps), you should be 

aware that the i.d. of even 1/8" schedule 40 pipe is 0.269-inch while the 

i.d. of 1/4" schedule 40 pipe is 0.364".



The i.d. of 3/8" aluminum tubing with 0.035 walls is 0.305-inch, which is 

smaller than 1/4" schedule 40 pipe, and not all that much larger than 1/8" 

schedule 40 pipe. The i.d. of 1/4" tubing with .035 walls is only 0.18". 

The flow area for the 3/8" tubing is 2.87  time greater than the 1/4" 

tubing. So average flow velocities are ~3x greater in the 1/4" tubing than 

in the 3/8" tubing. IIRC, pressure drop increases roughly as the square of 

velocity, so pressure drop in 1/4" tubing would be ~8x the pressure drop in 

the 3/8" tubing.



Terry

At 06:00 AM 3/8/2008 -0800, you wrote:

 	  Quote: 	
		  Because I'm in Canada and that is what is mandated.

 >From what I understand, the MD-RA (similar to DAR)

doesn't like any 1/4 inch in the fuel system at all.

Problem is, the Rotax has 1/4 inch fittings on the

pump and carbs.



Doug MacDonald

Do not archive


	




Terry Phillips

ttp44~at~rkymtn.net

Corvallis MT

601XL/Jab 3300 s .. l .. o .. o .. w build kit - Tail, flaps, & ailerons 

are done; working on the wings

http://www.mykitlog.com/N47TP/

_________________
Terry Phillips
Corvallis, MT
ttp44<at>rkymtn.net
Zenith 601XL/Jab 3300 slow build kit - Tail feathers done; working on the wings.

notsew_evets(at)frontiern
Guest

Posted: Sat Mar 08, 2008 9:12 am Post subject: Fuel System Questions

Another question:::



I have a Jabiru 3300A with one mechanical fuel pump.  Then I have an 

electric "boost" pump on the firewall...

This is how it came from Zenith.  My Cherokee has the same set up.  One 

boost and one mechanical....

I see that some XLs have a pump at each wing....

Please set me straight.  Whats the correct way to do the installation.....



SW

---

jeffrey_davidson(at)earth
Guest

Posted: Sat Mar 08, 2008 10:01 am Post subject: Fuel System Questions

SW,

	There are a multitude of postings in the archive about fuel systems

and fuel pumps.  In particular, see postings by "Hinde, Frank George

(Corvallis)" <frank.hinde(at)hp.com>  I don't believe Frank is still on the

list, but he had standing in fluid systems design.  In general, the

recommendation was to locate the Facet pumps as close to the fuel tank(s) as

possible.  This avoids "sucking" on the fuel which possibly could cause

vapor lock.  See Frank's posts for a more eloquent explanation.

       Jeff Davidson

Another question:::



I have a Jabiru 3300A with one mechanical fuel pump.  Then I have an 

electric "boost" pump on the firewall...

This is how it came from Zenith.  My Cherokee has the same set up.  One 

boost and one mechanical....

I see that some XLs have a pump at each wing....

Please set me straight.  Whats the correct way to do the installation.....



SW

Terry Phillips

Joined: 11 Jan 2006
Posts: 346
Location: Corvallis, MT

Posted: Sat Mar 08, 2008 10:40 am Post subject: Fuel System Questions

Steve



I believe that there are multiple correct ways, just different. I'm 

planning to burn mogas as much as possible. Mogas reportedly has a higher 

vapor pressure than avgas, and therefore the system can vapor lock at a 

lower temperature. If you read the instructions for the Facet 40105 pump, 

they say to mount it as close to the tank as possible. The electric fuel 

pumps that I've replaced on various automobiles have all been mounted just 

outside of the tank. Most modern cars have the electric pump inside the tank.



For my comfort, I decided to mount a fuel pump in each wing, between nose 

ribs 2 and 3. The 601XL standard design has a single pump on the firewall, 

with the gascolator poking through the cockpit floor just forward of the 

main spar. So, I'm adding a second fuel pump (1.2 lbs) and a second 

gascolator (0.6 lbs with fuel) and I'm using aluminum fuel tubing behind 

the firewall. Aluminum fuel tubing is used on most certified airplanes. It 

seems better to me.



The upside of wing fuel pumps is that vapor lock probability should be 

reduced. The downside is that fuel flows through the cockpit at higher 

pressure, so any leak there would be a more serious problem. So, you pays 

your money and you takes your chances.



Terry

At 10:08 AM 3/8/2008 -0700, you wrote:

 	  Quote: 	
		  Another question:::



I have a Jabiru 3300A with one mechanical fuel pump.  Then I have an 

electric "boost" pump on the firewall...

This is how it came from Zenith.  My Cherokee has the same set up.  One 

boost and one mechanical....

I see that some XLs have a pump at each wing....

Please set me straight.  Whats the correct way to do the installation.....



SW


	




Terry Phillips

ttp44~at~rkymtn.net

Corvallis MT

601XL/Jab 3300 s .. l .. o .. o .. w build kit - Tail, flaps, & ailerons 

are done; working on the wings

http://www.mykitlog.com/N47TP/

_________________
Terry Phillips
Corvallis, MT
ttp44<at>rkymtn.net
Zenith 601XL/Jab 3300 slow build kit - Tail feathers done; working on the wings.

bryanmmartin

Joined: 10 Jan 2006
Posts: 1018

Posted: Sat Mar 08, 2008 11:16 am Post subject: Fuel System Questions

It also depends on what type of fuel you intend to use. Avgas is a  

more uniform mixture than auto gas, it doesn't have the low boiling  

point components that auto gas has so it's more resistant to vapor  

lock than auto gas.



With auto gas, you want to make sure that the inlets to your pumps are  

gravity fed at all times (at least for the boost pump) You want the  

pressure in the fuel line to be above ambient pressure, the boiling  

point of gasoline decreases with a decrease in pressure. You don't  

want to draw a suction on a fuel line filled with auto gas, on a hot  

day, it could cause the fuel in the line to vaporize and fuel pumps  

won't pump vaporized fuel. That's also why you don't want to use any  

supply lines less than 1/4" ID. A liquid flowing through a tube will  

experience a pressure drop across the length of the tube, the smaller  

the tube, the faster the flow and the worse the pressure drop.



Putting the electric pumps in the wings at the outlet from the tanks  

pretty much guarantees you won't vapor lock the pumps, but it may be a  

bit of overkill. I put my fuel pumps on the cabin floor in the rudder  

cable tunnel just ahead of the gascolator near the lowest point of the  

system. In that location, they should be gravity fed in nearly any  

flight attitude or fuel state. The only possible way I can see vapor  

lock developing in my system is during a steep climb out at full  

throttle on a very hot day with a very low fuel level in the tank.  

That is a situation I don't intend to get myself into.



 	  Quote: 	
		   

 >



 Another question:::



 I have a Jabiru 3300A with one mechanical fuel pump.  Then I have an  

 electric "boost" pump on the firewall...

 This is how it came from Zenith.  My Cherokee has the same set up.   

 One boost and one mechanical....

 I see that some XLs have a pump at each wing....

 Please set me straight.  Whats the correct way to do the  

 installation.....




	




-- 

Bryan Martin

N61BM, CH 601 XL,

RAM Subaru, Stratus redrive.

do not archive.

_________________
--
Bryan Martin
N61BM, CH 601 XL, Stratus Subaru.
do not archive.

dougsnash(at)yahoo.com
Guest

Posted: Sat Mar 08, 2008 11:46 am Post subject: Fuel System Questions

The Rotax/Piersburg fuel pump has essentially a 1/4"

metal tube with a bulge crimped into the end of it for

a rubber fuel line to go over and be held on with a

hose clamp.  The fittings are welded/crimped to the

case of the pump and not changable.  So I suppose the

answer to your question would be, neither 1/4 NPT or

1/4 AN.



Fortunately, on the 701, we have gravity working for

us.  If this were a 601, I would definately be

installing dual Facets mentioned in another post.



Doug MacDonald

CH-701 Scatch Builder

NW Ontario, Canada



Do not Archive



--- Terry Phillips <ttp44(at)rkymtn.net> wrote:



 	  Quote: 	
		   

 <ttp44(at)rkymtn.net>

 

 Doug

 

 Are the 1/4" fittings on the pump and carb 1/4" NPT

 or are they 1/4" AN 

 tubing fittings?

 

 If they are NPT fittings (like on the Facet 40105

 pumps), you should be 

 aware that the i.d. of even 1/8" schedule 40 pipe is

 0.269-inch while the 

 i.d. of 1/4" schedule 40 pipe is 0.364".

 

 The i.d. of 3/8" aluminum tubing with 0.035 walls is

 0.305-inch, which is 

 smaller than 1/4" schedule 40 pipe, and not all that

 much larger than 1/8" 

 schedule 40 pipe. The i.d. of 1/4" tubing with .035

 walls is only 0.18". 

 The flow area for the 3/8" tubing is 2.87  time

 greater than the 1/4" 

 tubing. So average flow velocities are ~3x greater

 in the 1/4" tubing than 

 in the 3/8" tubing. IIRC, pressure drop increases

 roughly as the square of 

 velocity, so pressure drop in 1/4" tubing would be

 ~8x the pressure drop in 

 the 3/8" tubing.

 

 Terry


	


Never miss a thing.  Make Yahoo your home page. 

http://www.yahoo.com/r/hs

Terry Phillips

Joined: 11 Jan 2006
Posts: 346
Location: Corvallis, MT

Posted: Sat Mar 08, 2008 2:20 pm Post subject: Fuel System Questions

Doug



Now I see your problem more clearly. I have always planned on using ZAC's 

1/4" i.d. rubber tubing (inside a fire sleeve) FWF. That would mate fine 

with your fuel pump.



I doubt I can propose a better scheme than the one you suggested, but, 

perhaps, other alternatives. I don't see any way to go from 3/8" aluminum 

tubing to your 1/4" hose barb w/o using at least 3 AN fittings plus some 

1/4" i.d. hose.



Assuming you bring 3/8" aluminum through the firewall (eyeball fitting or 

bulkhead fitting), one alternative would be connect to an AN816-6-2D nipple 

to a AN910-1D coupling to a AN840-4D hose nipple and then run 1/4" i.d. 

rubber hose to the fuel pump.

One other thing I failed to mention in an earlier post. Bengelis recommends 

5052 aluminum tubing fo fuel lines rather than 3003, so that's what I ordered.



One item still on my shopping list is a tube flaring tool for the 37° AN 

flare fittings. They are $90 at Wicks. Summit racing has a 37° tool for 

~$32. Harbor Freight has a flaring tool for ~$12, angle unknown. Does 

anyone have experience with any of these? Or with a different satisfactory 

tool for a reasonable price? Thanks for any suggestions you can give me.



Terry

At 11:43 AM 3/8/2008 -0800, you wrote:

 	  Quote: 	
		  The Rotax/Piersburg fuel pump has essentially a 1/4"

metal tube with a bulge crimped into the end of it for

a rubber fuel line to go over and be held on with a

hose clamp.  The fittings are welded/crimped to the

case of the pump and not changable.  So I suppose the

answer to your question would be, neither 1/4 NPT or

1/4 AN.



Fortunately, on the 701, we have gravity working for

us.  If this were a 601, I would definately be

installing dual Facets mentioned in another post.



Doug MacDonald

CH-701 Scatch Builder

NW Ontario, Canada


	




Terry Phillips

ttp44~at~rkymtn.net

Corvallis MT

601XL/Jab 3300 s .. l .. o .. o .. w build kit - Tail, flaps, & ailerons 

are done; working on the wings

http://www.mykitlog.com/N47TP/

_________________
Terry Phillips
Corvallis, MT
ttp44<at>rkymtn.net
Zenith 601XL/Jab 3300 slow build kit - Tail feathers done; working on the wings.

dougsnash(at)yahoo.com
Guest

Posted: Sat Mar 08, 2008 8:05 pm Post subject: Fuel System Questions

I have the AS&S economy flaring tool for AN fitting

(37 Deg).  I have no idea how it will work out since I

haven't tried and falring yet.



It is likely the same on as Wicks is selling.



Doug MacDonald

CH-701 Scratch Bulder

NW Ontario, Canada



Do not archive

 

 	  Quote: 	
		   One item still on my shopping list is a tube flaring

 tool for the 37° AN 

 flare fittings. They are $90 at Wicks. Summit racing

 has a 37° tool for 

 ~$32. Harbor Freight has a flaring tool for ~$12,

 angle unknown. Does 

 anyone have experience with any of these? Or with a

 different satisfactory 

 tool for a reasonable price? Thanks for any

 suggestions you can give me.

 

 Terry

 


	


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