Leaking fuel compression fitting.

Inadvertantly banged the fuel line in some weather a few days back and noticed today a leak.
Tightened, no joy so pulled what I thought was the leaker apart (lower nut) and put some sealant (577) around the olive and tightened.
A few hours later, open tap and its obvious its the next compression fitting up which is not an olive but a flare.

Have given it the same treatment but I am wondering, why does the compression nut have holes in it?
What function, apart from leaking diesel, do they serve?

Hopefully its fixed, overnight to set before I turn the tap.

Simi,

It should be sealing on the angled face, so if that leaks it drains out the hole. The neck of the nut isn't designed to contain the potential pressure that could be trapped under that part of the nut. Also it ensures the nut cant be completely unscrewed with pressure on it.

Yeah, i did that in the first couple months of having Dauntless. I dropped the salon hatch (who knew it was so heavy) on to the Cu pipe.
It started leaking.
I went to hardware store and purchased the the flare kit, cutter and some Cu tube.
It was of the few jobs I've done on Dauntless that I actually fixed the first time, never to be heard of again.

Good luck

Richard

"I went to hardware store and purchased the the flare kit, cutter and some Cu tube."

Flares are superior to the flare nut concept.

If its not an emergency , purchase a Refrigeration grade flare tool.

These are about $30-$40 for the set but superb for quality non leaking work.

Sadly the fittings for real flare style use are more expensive than flare nut or house Pex fittings , so are seldom used in production boats.

Flares are reliable and preferred over compression fittings. The heavy flare nuts others referred to are forged and can be easily identified by the heavy construction. Machined nuts are well, machined from billet, and are more prone to distortion and leaks. It helps to use a hex wrench or flare nut wrench instead of an adjustable, avoids deforming the nut.

When forming a flare, be careful to first de-burr the end of the tube so there's no ridge. The better flare tool uses an eccentric action cone that rolls the flare over rather than straight on compression. Makes a significantly superior flare.

During my years running the HVAC service business, we adopted the protocol of using Leak Lock on flare joints, just a film on the face of the male fitting. We found it eliminated call-backs on refrigerant flare joints. It was never an issue with migration if applied properly. Insurance.

Compression fittings can be used in fuel lines, but it's not the preferred method. When we did use compression, we applied a film of Leak Lock on the ferrule (never heard it called an "olive" ) prior to assembly, rarely a leak unless it was disturbed. IMO, compression fittings on marine fuel lines would be an option ONLY as a stop-gap until a proper repair could be completed. Asking for a leak, and particularly bad for air ingress

I got so tired of the cheap flare tools from the hw store, I bought a mastercool hydraulic flare tool. Now I flare at every excuse, it’s sooo much easier and reliable. Came in handy when my hynautic steering lines needed replacing, and did complete custom brake lines on my cj8.

When I built my boat, I used flared copper for the whole steering system. Never before did flares. Used a cheap flare tool, hardware store fittings and refrigeration line. Guessing the system has about 75 flares (two helms, AP pump, reservoir, electric power steering, a bunch of tees, rudder cyl, etc). A few flex lines where needed.

I put the whole system together then filled it, pressurized it and bled it. Moment of dread: How many of these are going to leak??? Absolutely amazed. Not a single leak. It has now been ten years and 2400hrs and not a single leak.

Count me a as a believer in flares.

Hi,


The copper structure becomes harder when it is compressed, therefore, for example, the injection nozzle Cu tile gasket is changed every time it is opened. Another way is to heal the part of 300-500 C ° and the structure returns back to soft and the acid bath removes the oxide and gets a tight joint.


New Cu pipe is ok too...


NBs

Yeah well that was a fail.

Turned tap and started weeping again so pulled apart, cleaned up as best I could and try permatex #3.
If that doest work will have no choice but to try rescue tape until a flaring tool and supply of olives arrive via post.

Permatex 3 worked, ran engines still worked so left tap open overnight.
Went in er this morning and weeping again.

Yellow rescue tape time.
Hopefully that'll do the job until I get the gear to do a proper repair.

from a trusted source....

every boat should carry a handful of these things: http://secoseals.com/

You can get them in any size at any good a/c and refrigeration supply house for small money. Easy and quick permanent fix for anything other than a split flare from f'ing with it and overtightening while hoping for a miracle .........

Google "flare gaskets" for a ton of information and sources.

check the pipe at the flare very good with the nut back .if you can get it back with the compression fitting that close .it may be leaking through a crack where the flare starts .

psneeld said:

from a trusted source....

every boat should carry a handful of these things: Seco Seals - conical washer, metal gaskets, cones

You can get them in any size at any good a/c and refrigeration supply house for small money. Easy and quick permanent fix for anything other than a split flare from f'ing with it and overtightening while hoping for a miracle .........

Google "flare gaskets" for a ton of information and sources.

Click to expand...

Thanks for the heads up on these
Would appear to be a US thing, as yet I have found no oz supplier.
Looking.....looking.....

Oh and the rescue tape has done its thing.

FF said:

"I went to hardware store and purchased the the flare kit, cutter and some Cu tube."

Flares are superior to the flare nut concept.

If its not an emergency , purchase a Refrigeration grade flare tool.

These are about $30-$40 for the set but superb for quality non leaking work.

Sadly the fittings for real flare style use are more expensive than flare nut or house Pex fittings , so are seldom used in production boats.

Click to expand...

Question on size - refridgeration seems to use 45 degree flares but other uses (plumbing?) are 37 degrees. Which flare angle is used for hydraulic, water, and fuel lines? Confused here.

catalinajack said:

Question on size - refridgeration seems to use 45 degree flares but other uses (plumbing?) are 37 degrees. Which flare angle is used for hydraulic, water, and fuel lines? Confused here.

Click to expand...

Its not surprising that many people are confused about flared fittings.
JIC fittings are commonly used for some fuel and high pressure fluid hydraulic applications. They have a 37 degree flare. There are also JIS fittings on some Japanese equipment which have a 30 degree flare. There are also a variety of threads (SAE, BSP, metric) on all flared fittings.
Komatsu make there own line of flared fittings different from anyone else.

Refrigeration and air conditioning products usually use a 45 degree flare and an SAE thread.

Greetings,
Slight thread drift...the copper water lines on our boat (Asian origin) use flare fittings BUT seem to be metric of some sort, the threads of which are not compatible with North American flared fittings...

Straya, land of the rip off.
Those seco/conical seals that are but a few dollars in the US cost a hell of a lot more here.
I can buy them online for a few dollars from the US but then get slugged $50 in freight.

I think North was spell-checked...”annealed” is what he meant to say, copper, like stainless, gets work-hardened very quickly and this process removes the hardening in copper.

I think North was spell-checked...”annealed” is what he meant to say, copper, like stainless, gets work-hardened very quickly and this process removes the hardening in copper.

So........silicone rescue tape split today so searching for the conical washers again.
Still crazy expensive here so went to YouTube and found a cheap onsite solution.

Flat copper washers on eBay are $1.50 for ten delivered.
Flaring tool is $12 delivered
Flaring tool meet copper washer.
Flared copper washer meet gas flame to anneal.

catalinajack said:

Question on size - refridgeration seems to use 45 degree flares but other uses (plumbing?) are 37 degrees. Which flare angle is used for hydraulic, water, and fuel lines? Confused here.

Click to expand...

I would suspect every boat in US has 45 degree flares. (and probably every car and truck also) Double flare kits are inexpensive and readily available at any auto parts store or home depot. Single flare is OK but double flare is better for small dia lines.

If the flare has cracked you're probably going to replace the whole line or insert a new section at a minimum. You can use a flare union and 2 flare nuts to join 2 sections together.

SoWhat said:

Double flare kits are inexpensive and readily available at any auto parts store or home depot.

Click to expand...

Not in Australia they are not

Simi 60 said:

Not in Australia they are not

Click to expand...

$32.99A

https://www.amazon.com.au/Flaring-1...d=1521692179&sr=8-1&keywords=double+flare+kit

Simi 60 said:

Not in Australia they are not

Click to expand...

Is there a reason everything in Australia seems so expensive?

Comodave said:

Is there a reason everything in Australia seems so expensive?

Click to expand...

Wage levels. Little local manufacturing. Multi level supply chains. And greed.

SoWhat said:

$32.99A

https://www.amazon.com.au/Flaring-1...d=1521692179&sr=8-1&keywords=double+flare+kit

Click to expand...

Same one on eBay is $22 and freefreight
Kit that I got was $12 delivered as mentioned in my post a few up.

Sorry, it was the flared conical washers I was talking about.
$7 for 10 in the US plus $50 in freight even though they fit in an envelope.
Companies here sell them for the $7 + the $50 in freight plus their slice on top.

BruceK said:

Wage levels. Little local manufacturing. Multi level supply chains. And greed.

Click to expand...

And let's not forget to thank the purchaser for continuing to pay and therefore support the greed.