Gates Barricade standard carb fuel hose

[procharger]

What size fuel line runs from wings down to engine and how much is required

for total replacement CTSW thanks ?

[Tom Baker]

I posted totals in my parts list. It is the 7.5mm hose.

 

[Tom Baker]

10 hours ago, Roger Lee said:

The hose from the fuel bulkhead with the sight tube is only about 6" long. It is 5/16". It slides over a metal tube that runs down the "A" post into the engine compartment.

The hose is 7.5mm not 5/16", 5/16" is 7.95mm. I know you choose to use the 5/16" hose because it is cheaper, but it is to loose for my standards. The parts manual specifies a size and standard for the hose, and as far as I am aware Flight Design has not provided and approval for the 5/16" hose. It even became an issue when some mechanic used it on a CTLSi on the pressure side of the fuel injection system and the hose came off under pressure.

[Tip]

Where can you purchase 7.5 mm fuel hose?

[Jim Meade]

Roger, did you have get an LOA from RD to us the 5/16" hose?  I know you do extensive documentation on your work, do you write in the aircraft log that you changed from 7.5 mm OEM hose to a non-standard 5/16" hose per LOA, or do you just note the hose change without specifying it's a different dimension?  There is often discussion in SLSA circles over what original part the owner or mechanic can change on an SLSA on his own and what needs an LOA and I'm wondering about your experience with this.  I'd think a fuel line would be an item of interest to everyone.

[Tom Baker]

11 hours ago, Tip said:

Where can you purchase 7.5 mm fuel hose?

Airtime Aviation imports the OEM hose, and Flight Design USA sells a different brand. I have also used hose from a BMW dealer that meets the DIN specifications. The labeling on the hose is confusing, but it is the right size and works well. There is a brand called CRP that is out there, and I think CRP stands for crap. Where the other hoses will make a nice radius it wants to kink. The 7.5 mm hose is certainly more expensive than the Gates 5/16" hose, but that is the price to pay for following the rules.

[Tom Baker]

9 hours ago, Roger Lee said:

Been using 5/16" for 15 years and no issue. The .4mm (four tenths of 1mm) difference is negligible and actually fits better over barbed fittings and won't damage the inside liner. You can't pull my 5/16" hose off any fitting without tearing the hose. I'd say that is a tight fit. I have tested this twice. The hose will rip before it moves off those fittings.

If you want to see a really poor fit look at the hose the FD puts on the 912iS engine that comes off the fuel filter and into the first fuel rail. Their fitting is way too small and even using an Oetiker clamp will allow it to easily slide off. Ask me how I know and I even posted a bulletin on it. You must use a Band-It clamp like FD does from the factory to CRUSH the hose far enough so it won't slide off.

Roger, I agree that there are some fittings that the 5/16 hose fits better, and the 7.5 mm hose is really tight. But there are some fittings that will fall out of the end of the 5/16" hose without a clamp. Those fittings will leak if the clamp is not tight enough because the hose is to large for the fitting. 

For the 912iS if you use the correct size hose for the fitting you don't have issues. That .4 mm is a big factor then.

[Ed Cesnalis]

Gates says their barricade is not compatible with barbed fittings the barbs do cause damage and introduce debris  There is no correct size.  Beaded fittings are correct for this type of hose.

[Ed Cesnalis]

18 minutes ago, Roger Lee said:

So when trying to be overly technical where do you stop?

I say stop short of mixing barricade and barbed fittings.  It is a meaningful safety hazard.  I had to return to the field from a low altitude in a hostile environment and no motor thanks to the debris polluting my fuel system after a light sport repairman did the hose change.

[Ed Cesnalis]

2 minutes ago, Roger Lee said:

It wasn't the hose's fault.

if the correct beaded fittings where used it couldn't have happened.  it was the fault of the fitting/hose combination.  Even with your 'sterile' technique the barbs puncture the inner lining of the hose causing both debris and leakage beyond the inner lining. 

[Jim Meade]

Roger,

Who in FAA legal, or what document?  I'd like to see it, as well.  Thanks.

Did you or did you not get an LOA to change hose part numbers?  If not, what is your basis for the change if you get sued by someone who has a leaky fitting which is involved in an accident or incident?    I mean, if there is a problem and someone says, "who put this hose on here and on what authority" in court, what do you say?  As Tom say, the correct hose is available.  How does one defend a change unless there is an LOA?

 

 

[Jim Meade]

I have a question about the discussion over industry standards and best practice in such examples as the hose and barb we are discussing here.  The FAA has said that SLSA manufacturers can call certain maintenance shots.  If the manufacturer has used, calls out and provides parts and materials that many would not consider acceptable, where does one stand in challenging that position?  FD sells airplanes with barbed fittings and rubber hose.  These aircraft are reviewed by European regulatory bodies using published standards the FAA defers to.  What right does one have to argue that because some people think an item is less than optimal, that this perspective overrides the guidelines of the manufacturer who has to face the regulatory bodies?  

It seems to me there is probably some basic way in how to resolve these apparent conflicts.  Does anyone have history or can site precedent for how this dilemma is resolved?

[Madhatter]

I have eliminated all barb fittings and banjo fittings on all engine fuel fittings and soon will do all fittings and hoses on the airframe except for the wing root hoses. All new hoses are what you find in certified aircraft, lifetime teflon with silicon firesleeve. Same goes for the oil lines using AN fittings at the next rubber change. Overkill? I guess  but I won't have to deal with them again and they are much better and not as expensive as you would think. And yes I am ELSA .

[Tom Baker]

6 hours ago, Roger Lee said:

 If you want to get picky about the hose then you are required to order from FD any part that they have assigned a part number and you can not substitute. That comes right from the FAA legal. 

Roger, that is not quite right. I may have not been working on light sport aircraft as long as you, only since 2007, as an A&P I have been working on airplanes a long time. I have been an IA for over 30 years. Being an IA one of the ways you can renew is by doing training with the FAA. The FAA riling has been discussed in these training sessions since before the light sport definition was even formed. Here is an example Cessna list a wheel bearing with their part number in the parts catalog, and the description is simple wheel bearing. You pull the bearing out of the wheel and it is a Timken 12345. Even thought you can buy Timken 12345 since Cessna didn't specify Timken 12345 in the parts catalog you can only replace it with the Cessna part. Piper on the other hand also list the wheel bearing in their catalog with a Piper part number, but in the description it say Timken 12345. In this case it is okay to replace the bearing with a Timken 12345, that does not have the Piper part number. They are the same bearing, but it has to do with how it is listed in the parts catalog. So for Flight Design any part where they list a specification and size for the part it may be sourced from anywhere, but if it just has a Flight Design part number and says hose it must be bought from them. That is what the FAA legal ruling says in a nut shell.

[Tom Baker]

2 hours ago, Roger Lee said:

Tom,

This is what FAA told me.

 

What they told you is partly true, but there are exceptions.

[Jim Meade]

I understand that everyone is expressing heart-felt understandings and beliefs, but it sure would be nice if posts could include or cite names, places, times, documents and so forth.  Otherwise, it turns into "trust me".  When we talk about maintenance procedures, our work should be able to be cross-checked and reproduced.  We're all human and we're all subject to selective recollection or understanding, especially in an emotional discussion.  If it comes down to "trust me", we are really dealing with personalities and not facts.

I think I recall very few of my "show the source" inquiries answered.  Not answering them is answering them.

If a poster is forced to say, "I heard it at school" or I heard it at an IA refresher course" it would be better if one could say about when, about where, the instructor if remember, etc.

 

[Jim Meade]

8 hours ago, Roger Lee said:

I have talked with several factories over the years about buying parts locally and or not from them. Most didn't care.

That's my point. 5/16" or 7.5 mm. Mfg's don't really care. Look at the parts you buy from me. The original door lift struts were only 190 psi and I got them to 220. The original red polyurethane dampeners were 20mm wide and now 25mm.

What factory and what product?  What manufacturer - the hose manufacturer?  I don't suppose the hose manufacture does care. 

We see too much selective discussion of what takes an LOA and what does not.  I believe many people "don't care" but if the issue is only some rules really apply, then how does the forum reader know which rules?  So he changes his SL40 out for an SL30 - hey! what difference does it make?  We use Ace Hardware for nuts and bolts.  We use non-OEM, off-size hose because it's cheaper and "close enough".  What's the big deal?  (asked with sarcasm in case it didn't come through).

 

 

[Madhatter]

I have talked to a number of senior FAA individuals I have known for about 20 yrs and was privately told they are not interested in LSA. However if you have an incident due to being stupid about something,  they will get interested. 

[Tom Baker]

9 hours ago, Roger Lee said:

I have talked with several factories over the years about buying parts locally and or not from them. Most didn't care.

That's my point. 5/16" or 7.5 mm. Mfg's don't really care. Look at the parts you buy from me. The original door lift struts were only 190 psi and I got them to 220. The original red polyurethane dampeners were 20mm wide and now 25mm.

Roger, door lift struts that are a little longer or stronger is not an issue. Having slightly larger diameter suspension dampers is not a safety issue, in fact Flight design uses the larger dampers for the CTLS. My issue with the hose that you say .4 mm is insignificant is that there are some fittings in a CTSW that if inserted in the hose with just some slight shaking will fall out because they are to loose is a safety issue. I know the you can tighten the clamp down to stop the fuel from leaking, but the hose should seal on the fitting without a clamp. BTW you can not shake the fittings out of the 7.5 mm hose. There are as many as 13 places about half of the fuel fittings on a CTSW where the 5/16" hose is too loose for the fitting in my opinion. 

[Warmi]

6 hours ago, Madhatter said:

I have talked to a number of senior FAA individuals I have known for about 20 yrs and was privately told they are not interested in LSA. However if you have an incident due to being stupid about something,  they will get interested. 

That’s a blessing.

[Jim Meade]

It's black and white.  There are standards and protocols and ways to deal with needs for exceptions in maintaining SLSA.  The alternative is ELSA with more flexibility.

Trying to meet the letter of the law for SLSA without using SLSA protocols finds us justifying, explaining, excusing, rationalizing and so forth but still wrong.

We set ourselves up to be the authority when we do that.  When others look to us for guidance or perspective and we offer non-SLSA alternatives to an SLSA issue, we support others breaking the rules.

Many find the need to choose between SLSA and ELSA conflicting.   They want to have their SLSA cake and eat it with an ELSA fork.

The Part 91 tradition of aircraft maintenance is keep it flying and minimal expense.  A&Ps would apply their rationale to the fitness of various materials and procedures.  "Oh, that hose will last till next annual".  There is tremendous pressure for SLSA owners to find mechanics who will apply that same "let it slip by" standard but the rules are different.  Hence the conflict.

Of course this is all very easy to say.  It is also very easy to do.  Except when we don't like it.

 

 

 

 

 

[Tom Baker]

10 hours ago, Roger Lee said:

So what's the difference from FD with the hose and fitting on the 912iS engine. The hose out of the fuel filter to the first 90 degree fitting on the fuel rail. The hose is way too big. It's like putting a 5/16" on a 1/4" fitting and that's from the factory. The only way they make that work is to use a Band-It clamp and tighten it way down.

Roger,

I've only done one hose change on CTLSi. At the time I ask you and you had not performed one yet. It has been a few years now, and I don't remember it being too loose. I do remember checking it after the caution about it coming out, and it still seemed tight.

10 hours ago, Roger Lee said:

My 5/16" is better than the 7.5mm on the barbed fittings because mine isn't fuel injection hose (stiff with no give) and it slides over the barbed fittings like it should without damaging the inner liner. You said in a post above that sometimes their hose was a little tight over the fitting. That says it all. FD in Europe uses 7.5mm because that's what they have. Metric. 

The Gates fuel injection hose is very stiff. One of the 7.5 mm hoses I tried was also very stiff. I have used at least 3 different 7.5 mm fuel injection hoses that stretched as well as the Gates carb hose. BTW the 5/16" hose is to tight over the same fittings, so it is a wash in my mind.

 

10 hours ago, Roger Lee said:

he hose fittings you mentioned above being too loose on the fittings. So is the 7.5mm. FD made those fittings too small too. The fittings stainless tubing on the SW's are only 1/8" ID. They slide off too without a good clamping down. Rotax wants 5/16 minimum for a supply to the fuel pump. You can't complain about one thing and not say the same thing about everything else.

I call BS I have a stainless "T" fitting from Flight Design right here, the ID measures .235. I also happen to have a hose fitting for a Rotax fuel pump inlet, and it measures .218 ID. They may call for a 5-16" hose, but the ID of the fittings will always be less than 5/16". With the 7.5 mm hose you can slide it on the fitting, and it doesn't fall out like it does with the 5/16" hose.

 

10 hours ago, Roger Lee said:

The door struts and dampeners aren't made by or for FD, but you still use them. Technically you should only use theirs. 

I agree somewhat, but in the case of the door struts and dampers it is not a safety issue. My bottom line is SAFETY comes first.

 

10 hours ago, Roger Lee said:

You're targeting one little thing and letting everything else slide, plus the 5/16" is a better fit over the barbed fitting compared to the 7.5mm.

When given the choice about the hose being too tight on 4 fittings or being too loose on 11 fittings, I am going to choose having it too tight on the four fittings. I would much rather have the hose be to tight than risk a fuel leak from being too loose.

 

10 hours ago, Roger Lee said:

You buy Odyssey batteries. Why not Hawker batteries like FD used. Just like 7.5mm hose that's what they used in Europe,

Because there is a Flight Design approval for the Odyssey battery, unlike the 5/16" fuel hose.

[Warmi]

2 hours ago, Jim Meade said:

It's black and white.  There are standards and protocols and ways to deal with needs for exceptions in maintaining SLSA.  The alternative is ELSA with more flexibility.

Trying to meet the letter of the law for SLSA without using SLSA protocols finds us justifying, explaining, excusing, rationalizing and so forth but still wrong.

We set ourselves up to be the authority when we do that.  When others look to us for guidance or perspective and we offer non-SLSA alternatives to an SLSA issue, we support others breaking the rules.

Many find the need to choose between SLSA and ELSA conflicting.   They want to have their SLSA cake and eat it with an ELSA fork.

The Part 91 tradition of aircraft maintenance is keep it flying and minimal expense.  A&Ps would apply their rationale to the fitness of various materials and procedures.  "Oh, that hose will last till next annual".  There is tremendous pressure for SLSA owners to find mechanics who will apply that same "let it slip by" standard but the rules are different.  Hence the conflict.

Of course this is all very easy to say.  It is also very easy to do.  Except when we don't like it.

Oh it is never black and white , as owners we do make choices all the time. For instance the principle I follow is  something like .. , if this is not a structural item and does not affect safety in any way , directly or indirectly  -  I won't bother with LOA or any of that non-sense just to comply with some rules.

What I am talking about here items like iPad mounts or similar minor items in the cabin - if I want to drill my panel and permanently install a mount, I will do so and not worry about wasting time on LOA even though this is a permanent modification and theoretically I need their approval for that.

On the other hand, I won't even think about substituting an oil filter or anything that I don't understand potential implications of changing because , well, because I do fly this plane and it is my ass on the line and there is nobody out there who is more invested in preserving safety of my "behind" than me.

 

 

[Jim Meade]

If one doesn't agree with the rules, one can go ELSA as I and many other have.

[Warmi]

2 hours ago, Jim Meade said:

If one doesn't agree with the rules, one can go ELSA as I and many other have.

I certainly will if I ever decide to install an aftermarket fuel injection kit or something along these lines .. and I will seek LOA if I decide to install custom avionics and such but I did spend $100k on the plane and I feel I don’t need anybody’s permission to make minor cosmetic changes.