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Proper technique for fuel line clamps

My fuel lines were leaking a bit between the line and the clamp on my quick disconnects. As soon as it gets warm enough, I am going to replace the lines and clamps. ( R1150RT)

What is the proper technique for tightening the clamps?

How close to the end of the hose should the clamp be?
How do I know when the clamp is tight enough, or too tight?
 
The clamp should be aboat midpoint in the male fitting inserted into the hose.

I snug them up until I can see the hose deform slightly. Beyond that is overkill.
 
I assume that you have the OEM clamps made by Swiss mfg. Oetiker.
There was a recall years ago where these clamps came loose and leaked. You can simply re-tighten them and all will be well.
They sell a special tool which is essentially a front cutter with dulled edges.
See here:
http://chadstoolbox.com/1098oetikerclamppliers.aspx
I use a regular (sharp) front cutter (no worries, you won't be able to cut the clamp). This worked well to tighten the clamps to the point where they no longer leak.
I also have been sucessful prying the clamps open with small screwdrivers, changing out the quick disconnects for steel ones (Beemerboneyard carries them), then tightening the old clamps back up with the cutters.
 
I assume that you have the OEM clamps made by Swiss mfg. Oetiker. .

Thanks for the reply. I took those off when I put on the quick disconnects.
The clamps I'll be putting on are the solid screw type that came with the fuel line replacement kit from beemerboneyard.
 
It may be just my opinion, but it seems to me the Oetiker clamps save BMW a little time in the original assembly in the factory but are a maintenance headache thereafter unless you have a supply of new ones and a somewhat proper tool. Prying off and then rebending to use them again is a kludge. I don't go out of my way to replace them all but I do replace them any time I have need to remove or loosen one. And I don't replace them with Oetiker clamps. Good for manufacturing doesn't always equate to good for maintenance.
 
The caution with any form of hose clamp, is over tightening the clamp in an area close to a step or barb on the stub the hose passes over, or if the clamp is placed right where the hose bends. If over-tight, the stress on the hose inner tube can actually cause a cut or tear in the inner tube of the hose. If this happens, the liquid may get between the inner tube and outer cover, which causes "wetting" on the hose cover or possibly hose cover blisters.
 
Fuel line type

Greetings, All - NOT to hi-jack the thread, but this seems legit. . .

One of my several winter projects is the installation of quick-disconnects on the fuel lines of my '94 RS -- Pretty sure these are the ORIGINAL lines, and I've bought the beemerboneyard hose clamps.

Q: Is there some kind of certified Teutonic fuel line needed???? Or, will any AutoZone "pressure" fuel line (of appropriate diameter) work???

This info is probably skillfully hidden behind the impenetrable firewall of the Search Engine on this site -- too bad that same technology wasn't used by the government; Wikileaks wouldn't have stood a chance. . .

Thanks (again) for all the help available on this site.

Paul - the information you gave on lubing the splines correctly probably saved my a_ _, or maybe just the clutch. . .but THANKS for the detailed tip - I bet a lot of techs have goofed this one over the years, and -for sure- a lot of semi-skilled (emphasis on "semi") shadetree guys have done it wrong, and wondered why the clutch slipped.

We soldier on.

Walking Eagle
 
If the hose is rated as fuel hose, and is rated for the pressure of the fuel injection system then it should be fine. Must likely it will have a Nitrile inner tube which should work ok for the temperature ranges on a bike. But if possible, check the temperature rating of the hose if available.

Without knowing more specifics on the hose I can't say how long it would last. It must also be a hose that is UV stable (Ultraviolet resistant) because on a bike the hose will be directly exposed to sunlight more so than on a car under the hood. A hose that is not UV stable WILL harden and crack simply due to direct sun exposure.

I used to work for Dayco before Parker, and Dayco made most of the hose commonly found at auto parts retailers, like NAPA and Auto Zone. Here is a link to more details on injection fuel hose:

http://www.daycoproducts.com/daycow...1f110345eb637790862571aa006e7b5c!OpenDocument
 
If the hose is rated as fuel hose, and is rated for the pressure of the fuel injection system then it should be fine. Must likely it will have a Nitrile inner tube which should work ok for the temperature ranges on a bike. But if possible, check the temperature rating of the hose if available.

Without knowing more specifics on the hose I can't say how long it would last. It must also be a hose that is UV stable (Ultraviolet resistant) because on a bike the hose will be directly exposed to sunlight more so than on a car under the hood. A hose that is not UV stable WILL harden and crack simply due to direct sun exposure.

I used to work for Dayco before Parker, and Dayco made most of the hose commonly found at auto parts retailers, like NAPA and Auto Zone. Here is a link to more details on injection fuel hose:

http://www.daycoproducts.com/daycow...1f110345eb637790862571aa006e7b5c!OpenDocument
Is the hose mentioned in this link UV stable?
 
One of my several winter projects is the installation of quick-disconnects on the fuel lines of my '94 RS --
Is there some kind of certified Teutonic fuel line needed???? Or, will any AutoZone "pressure" fuel line (of appropriate diameter) work???
Just did that too and installed an external filter. One of the the tutorials on replacing the filter stated "get 6 feet of fuel injection rated line". I bought mine from NAPA. Rated at 80psi. However it was $8.50 a foot. So I opted for 3 feet with the intention of buying any extra that I would need in 1 foot increments. Happily 3 feet was enough. I am a cheap bastard.
 
Just did that too and installed an external filter. One of the the tutorials on replacing the filter stated "get 6 feet of fuel injection rated line". I bought mine from NAPA. Rated at 80psi. However it was $8.50 a foot. So I opted for 3 feet with the intention of buying any extra that I would need in 1 foot increments. Happily 3 feet was enough. I am a cheap bastard.

You may well be a cheap ba$tard, but NOT buying 2 times what you need does not make you so.

Fuel injection rated hose is expensive.

Mark
 
Can't say with absolute certainty, but Parker hoses, Dayco hoses, Aerquip, Gates, Weatherhead, the big names in hoses almost all make the hose materials UV stable. Stick wiht the big names brands for good quality.

I would not depend on that if the hose came from some unknown off-shore supplier from China, Korea, India, Malaysia, and the many other countries that produce a variety of hoses. Cheap hose is just that, cheap, and not all hose is created equal by any measure, even those built to the same SAE specs.
 
I remember reading that fuel line rated for fuel injection systems is fine if it's an external line (outside the tank). However, if replacing any line inside the tank, it has to be rated as "submersible" to prevent the breakdown of the outer material. Anyone else care to verity this? I Googled it, and found one of many links:

http://www.frsport.com/Gates-27093-...Hose-For-In-Tank-Lines-SAE-30R10_p_15937.html

BTW, both types of line can usually be purchased at your local NAPA dealer.
 
I remember reading that fuel line rated for fuel injection systems is fine if it's an external line (outside the tank). However, if replacing any line inside the tank, it has to be rated as "submersible" to prevent the breakdown of the outer material.

To bypass the fuel filter inside the tank you only need 10" so at $20/foot you would not break the bank unless you only have $19 in the bank. I did not check if the hose I bought from NAPA was submersible but it certainly is submersed now.
 
To bypass the fuel filter inside the tank you only need 10" so at $20/foot you would not break the bank unless you only have $19 in the bank. I did not check if the hose I bought from NAPA was submersible but it certainly is submersed now.

When I install external filters I don't add any submerged hose inside the tank at all. I use copper tubing (lavatory supply line) cut to length to fit in the original location instead of the filter. Then I use injection rated fuel line for the external installation.
 
When I install external filters I don't add any submerged hose inside the tank at all. I use copper tubing (lavatory supply line) cut to length to fit in the original location instead of the filter. Then I use injection rated fuel line for the external installation.

That is a great alternative. I wish I had known that before I did my bypass.

Good one Paul
 
I remember reading that fuel line rated for fuel injection systems is fine if it's an external line (outside the tank). However, if replacing any line inside the tank, it has to be rated as "submersible" to prevent the breakdown of the outer material. Anyone else care to verity this? I Googled it, and found one of many links:

http://www.frsport.com/Gates-27093-...Hose-For-In-Tank-Lines-SAE-30R10_p_15937.html

BTW, both types of line can usually be purchased at your local NAPA dealer.

I did not use the submersible line in my tank when I did my externalization. I after 90K miles I decided to swap out all my fuel lines. I was a little worried to see what I would find when I opened up the tank. The non-submersible line was fine. In fact, the writing on the line was still plainly visible.

So IMO if you have submersible line, great. Use it. If you didn't use it, don't sit up at night worrying. it's fine.
 
Another aspect of hoses: the outer cover layer is there mostly just to protect the hose reinforcement (be it fabric or wire) and to provide a surface to imprint hose details and manufacturing info. As such its usually the cheaper part of the hose material choices that are applied.

So, a hose with a fuel compatible inner tube, "may" not have a fuel compatible outer cover, at least for 100% exposure/submerssion in fuel. But other factors apply, like temperature. Most hose covers will last a LONG time in submerssion if the liquid temperature does not exceed about 150 degrees F. In the case of a cycle fuel tank, that high a temperature, over extended constant exposure, is not likely. So, given all that, a neoprene (most common) or nitrile cover (also very common) will last just fine within the typical service intervals.
 
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