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Blown oil hose CJ - connectors?
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jay-dub



Joined: 31 May 2014
Posts: 99
Location: UK

PostPosted: Sun Jul 30, 2017 12:44 pm    Post subject: Blown oil hose CJ - connectors? Reply with quote

It's all happening...

Just prior to shutdown (luckily), the hose from the engine to the oil cooler let go just aft of the firewall but before the cockpit, resulting in hot oil spraying out and now seeping from just about every panel and flooding the right side of the cockpit. No injuries fortunately.

We can replace the hose easily enough but the issue is the connectors. The existing ones don't appear to be reusable - unless someone here knows different.

Are they standard AN connectors? I expect not but if so, no dramas. If not, what are they and where can I get them please?


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pilotdog57(at)aol.com
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PostPosted: Sun Jul 30, 2017 2:15 pm    Post subject: Blown oil hose CJ - connectors? Reply with quote

When some of mine were changed we used a pipe wrench with the hose firmly clamped into a vice. It marked them up a little but they were reusable.

Sent from my iPhone

Quote:
On Jul 30, 2017, at 2:44 PM, jay-dub <flyjnw(at)gmail.com> wrote:



It's all happening...

Just prior to shutdown (luckily), the hose from the engine to the oil cooler let go just aft of the firewall but before the cockpit, resulting in hot oil spraying out and now seeping from just about every panel and flooding the right side of the cockpit. No injuries fortunately.

We can replace the hose easily enough but the issue is the connectors. The existing ones don't appear to be reusable - unless someone here knows different.

Are they standard AN connectors? If so, no dramas. If not, what are they and where can I get them please?

--------
CJ and Yak-52 owner




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dsavarese0812(at)bellsout
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PostPosted: Sun Jul 30, 2017 4:12 pm    Post subject: Blown oil hose CJ - connectors? Reply with quote

They are definitely not AN fittings! They are metric. Remove the hose and find a hose fabrication shop that will remove the ends off the hose and reuse the metric nuts or give Cliff Coy a call at Border Air in Swanton, VT.  Cliff can remake the hose using your hose ends and metric hose. 802-868-2822.
Dennis

From: jay-dub <flyjnw(at)gmail.com>
To: yak-list(at)matronics.com
Sent: Sunday, July 30, 2017 4:45 PM
Subject: Blown oil hose CJ - connectors?


--> Yak-List message posted by: "jay-dub" <flyjnw(at)gmail.com (flyjnw(at)gmail.com)>

It's all happening...

Just prior to shutdown (luckily), the hose from the engine to the oil cooler let go just aft of the firewall but before the cockpit, resulting in hot oil spraying out and now seeping from just about every panel and flooding the right side of the cockpit. No injuries fortunately.

We can replace the hose easily enough but the issue is the connectors. The existing ones don't appear to be reusable - unless someone here knows different.

Are they standard AN connectors? If so, no dramas. If not, what are they and where can I get them please?

--------

CJ and Yak-52 owner

Read this topic online here:

http://forums.matronics.com/viewtopic.php?p=471357#471357

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wlannon(at)shaw.ca
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PostPosted: Sun Jul 30, 2017 9:56 pm    Post subject: Blown oil hose CJ - connectors? Reply with quote

That is a very disturbing report. Such a failure in flight could be
catastrophic. These are old to very old aircraft, some in the order of 50 +
years and the oil cooler hoses are very difficult to replace or even
inspect.
The oil out hose is probably the most critical one in the aircraft due to
high temperature and the fact that scavenge pump pressure is unregulated.
Were this a certificated aircraft there would likely be an AWD on the
subject.

Jay-dub could you provide some pics and description of the failure when you
get a chance?

Condolences and Thanks;
Walt
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Harv



Joined: 01 Jul 2010
Posts: 172

PostPosted: Mon Jul 31, 2017 5:06 am    Post subject: Re: Blown oil hose CJ - connectors? Reply with quote

Sorry to hear!

This is exactly why we have a 3 year periodic hose pressure test, of course that only goes so far though I've never heard of this happening before so is fortunately extremely rare.

I do have spare main lines and some old fittings (from when i replaced my hoses with new ones) if you need something to use until your's are removed from the a/c

Harv


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richard.goode(at)russiana
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PostPosted: Mon Jul 31, 2017 8:25 am    Post subject: Blown oil hose CJ - connectors? Reply with quote

We have spent a lot of time on this issue of flexible hoses. The first
problem came when the Russians would only sell huge quantities of hose and
very unreliable deliveries. However we realised that we could not fit good
quality Western hose – we decided that Aeroquip 404 was the best – onto the
Russian metal fittings reliably. Of course you can do what seems an adequate
job, but when subject to excessive pressure and heat we found that the ends
would leak or possibly worse.

We spent a lot of time researching the issue, and have now developed a
system to modify the Russian metal ends to take Aeroquip 404 hose, and, for
that matter, repetitively in the future. Very importantly we have the
authorisation to give EASA "form1" documentation for these hoses – the
highest European document aviation quality, and with a 10 year life.
Richard Goode
Rhodds Farm
Lyonshall
Hereford
HR5 3LW
United Kingdom
 Tel: +94 (0) 81 241 5137 (Sri Lanka)
Tel:   +44 (0) 1544 340120
Fax:  +44 (0) 1544 340129
www.russianaeros.com
I’m currently in Sri Lanka but this Mail is working,and my local phone is
+94 779 132 160.

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wlannon(at)shaw.ca
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PostPosted: Mon Jul 31, 2017 8:59 am    Post subject: Blown oil hose CJ - connectors? Reply with quote

After reading and re-reading your description of replacing hose end fittings
I felt a reply was really necessary.

"We used a pipe wrench with the hose firmly clamped into a vise" is a
perfect example of how to not to do this job.

This process pretty much guarantees a permanently (maybe fatally) damaged
hose structure and a fitting now subject to corrosion and fatigue cracking
due to pipe wrench damage.

Walt

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wlannon(at)shaw.ca
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PostPosted: Mon Jul 31, 2017 9:42 am    Post subject: Blown oil hose CJ - connectors? Reply with quote

Hi Richard:

Are you referring specifically here to the engine oil system hoses? Or the
aircraft hoses in general? If the latter I would most certainly agree.

Referring here to Chinese rather than Russian I have found that the oil
hoses and end fittings are virtually dimensionally identical and appear
functionally interchangeable with MIL H 8794 -12 Med. Press. hose (Aeroquip
303-12 or Stratoflex 111-12).

Conversion of all other hose sizes on the CJ6 are highly questionable at
best.

Cheers;
Walt
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dougsappllc(at)gmail.com
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PostPosted: Mon Jul 31, 2017 9:46 am    Post subject: Blown oil hose CJ - connectors? Reply with quote

Guys,I have current manufacture date oil hose assemblies in stock.  
Was the failure actually a fitting failure or a hose failure?
Was it a stock assembly or was it a "shop made" hose?
Making hoses is akin to playing with fire unless you know what you are doing and have the right tools (proper mandrels, not pipe wrenches).  Unless you fully understand the process and know how to correctly check for proper dept of hose inside the collar, "flappers" and other gotchas, you'd best leave the job to someone more experienced, personally I am not willing to accept the liability so I do not make or sell re-manufactured hoses.  
Doug
Virus-free. www.avast.com [url=#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2][/url]

On Sun, Jul 30, 2017 at 5:10 PM, A. Dennis Savarese <dsavarese0812(at)bellsouth.net (dsavarese0812(at)bellsouth.net)> wrote:
Quote:
They are definitely not AN fittings!  They are metric.  Remove the hose and find a hose fabrication shop that will remove the ends off the hose and reuse the metric nuts or give Cliff Coy a call at Border Air in Swanton, VT.  Cliff can remake the hose using your hose ends and metric hose.  [url=tel:(802)%20868-2822]802-868-2822[/url].
Dennis

From: jay-dub <flyjnw(at)gmail.com (flyjnw(at)gmail.com)>
To: yak-list(at)matronics.com (yak-list(at)matronics.com)
Sent: Sunday, July 30, 2017 4:45 PM
Subject: Blown oil hose CJ - connectors?


--> Yak-List message posted by: "jay-dub" <flyjnw(at)gmail.com (flyjnw(at)gmail.com)>

It's all happening...

Just prior to shutdown (luckily), the hose from the engine to the oil cooler let go just aft of the firewall but before the cockpit, resulting in hot oil spraying out and now seeping from just about every panel and flooding the right side of the cockpit. No injuries fortunately.

We can replace the hose easily enough but the issue is the connectors. The existing ones don't appear to be reusable - unless someone here knows different.

Are they standard AN connectors? If so, no dramas. If not, what are they and where can I get them please?

--------

CJ and Yak-52 owner

Read this topic online here:

http://forums.matronics.com/viewtopic.php?p=471357#471357


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jay-dub



Joined: 31 May 2014
Posts: 99
Location: UK

PostPosted: Tue Aug 01, 2017 1:16 am    Post subject: Re: Blown oil hose CJ - connectors? Reply with quote

Here is a photo of the failure, after some cleaning. The failure was actually a split in the upper braided hose about 1/2 inch from the connector. It would appear it is not the standard hose. The hose has now been removed.

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richard.goode(at)russiana
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PostPosted: Tue Aug 01, 2017 8:01 am    Post subject: Blown oil hose CJ - connectors? Reply with quote

Hello Walt,

I know nothing about the Chinese hoses, but I find it difficult to think that they are going to be significantly different to the Russian. The cautionary point of my posting was that the Russian metal ends will not make a perfect seal with Western hose, such as Aeroquip 404 unless they are modified. You can seem to get a seal, but it is not strong, and I certainly would not want to fly with such a join!

Richard Goode

Rhodds Farm
Lyonshall
Hereford
HR5 3LW
United Kingdom
Tel: +94 (0) 81 241 5137 (Sri Lanka)
Tel: +44 (0) 1544 340120
Fax: +44 (0) 1544 340129
www.russianaeros.com
I’m currently in Sri Lanka but this Mail is working,and my local phone is +94 779 132 160.

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wlannon(at)shaw.ca
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PostPosted: Tue Aug 01, 2017 11:53 am    Post subject: Blown oil hose CJ - connectors? Reply with quote

Jay-dub;

That is an AN standard, Aeroquip #491 fitting assy. on what looks like an
Aeroquip 303 hose but I do not recognize the location as "just aft of the
firewall" in a CJ6.
There should be no oil hose connection in that immediate area at all. Can
you confirm this is the lower RH firewall area of a CJ6.

The MIL H 8794 (303) hose has a layer of steel wire braid below the outer
fabric cover. The failure you have suffered is almost inconceivable
without pre-existing external damage.

Also do not recognize the two small dia. (Chinese or Russian) hose
connectors below the large (-12) hose as a CJ6 assembly. The upper small
dia. hose is similar to an Aeroquip 600 series (probably a Russell
knock-off) and is not compatible with the Chinese/Russian end fitting.

Walt

From: jay-dub
Sent: Tuesday, August 01, 2017 2:16 AM
To: yak-list(at)matronics.com
Subject: Re: Blown oil hose CJ - connectors?



Here is a photo of the failure, after some cleaning. The failure was
actually a split in the braided hose about 1/2 inch from the connector. It
would appear it is not the standard hose. The hose has now been removed.

--------
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jay-dub



Joined: 31 May 2014
Posts: 99
Location: UK

PostPosted: Wed Aug 02, 2017 9:54 am    Post subject: Re: Blown oil hose CJ - connectors? Reply with quote

Thanks, Walt.

The removed external panel is just aft of the firewall on the lower right side of the forward fuselage. I'm interested in your comments above as we have no immediate means of comparison. If I get chance, I will ask to open the same panel on one of the other two Huosai powered CJs in the UK to see.

For the avoidance of doubt, the hose which failed is the middle one of the three in the picture - the silver coloured one.


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Robin Hou



Joined: 19 Jan 2017
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Location: El Monte, CA

PostPosted: Wed Aug 02, 2017 10:35 am    Post subject: Re: Blown oil hose CJ - connectors? Reply with quote

Jay-Dub, do you oil hoses pass through the firewall with fittings?

On my 85 CJ-6 both oil hoses run through the firewall via grommets without fittings. My oil hose is Chinese so I assume they are original since 1990's when it was exported to the U.S.

I have considered adding fittings as firewall pass through when I replace the oil hose. However, the firewall is only aluminum so any benefit of the fittings may not be realized in case of fire.


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jay-dub



Joined: 31 May 2014
Posts: 99
Location: UK

PostPosted: Wed Aug 02, 2017 11:06 am    Post subject: Re: Blown oil hose CJ - connectors? Reply with quote

They go through the firewall with grommets.

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Harv



Joined: 01 Jul 2010
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PostPosted: Wed Aug 02, 2017 11:36 am    Post subject: Re: Blown oil hose CJ - connectors? Reply with quote

So the pic is you posted is taken looking through the STB side fuselage access panel which makes more sense.

I'm with my aircraft tonight so will take a picture for you.

The only possibly explanation I can think right now is someone has done a very nasty modification with the engine oil feed line to the cooler buy adding a fitting and running two smaller hoses (possibly for ease of replacement??) rather than obtain a new Chinese hose.

It has certainly doubled the failure mode (as you have found out) and I'm quite surprised whoever maintains your AC hasn't insisted this was removed (that's just my 2pence worth) in the normal course of performing the 3 year periodical hose pressure test Shocked but that assumes they "know" these aircraft.


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Harv



Joined: 01 Jul 2010
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PostPosted: Wed Aug 02, 2017 1:40 pm    Post subject: Re: Blown oil hose CJ - connectors? Reply with quote

Oil hoses running through the firewall, the fitting you see connects to the excellent Craig Payne oil filter bypass system

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PostPosted: Wed Aug 02, 2017 8:18 pm    Post subject: Blown oil hose CJ - connectors? Reply with quote

Jay-dub;

Attaching a photo taken inside the RH lower, forward, fuselage panel
(approx. 5" X 7") just aft of the firewall and above the floor. The LH
side has an identical panel in the same location. The two oil hoses you see
(though new a few years ago) are exactly as original. They are approx. 6
ft. long and join the oil cooler hoses in the area of an access panel under
the RH fwd. wing LE/fuselage fairing.
All you see in the photo is stock, with the exception of my 24/12 voltage
converter at the bottom. In the upper LH corner is the fuel pressure
transmitters the hose connector for which attaches on the fwd. side of the
firewall.
In the lower RH corner of the photo there is a heavy metal section which is
the inboard side of the RH lower longeron. This is a wide, "U" shaped
structure (one of four) which carries the major fuselage loads.

In viewing your photo the longeron is also visible (full of oil) but is
located in the LH lower corner of the image. If the photo as taken aft to
fwd as the firewall image appears to suggest I am really confused.

Mine is a 1965 version and at least to the late 1970's this area is
unchanged. Maybe not true of later models?

Cheers;
Walt

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jay-dub



Joined: 31 May 2014
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PostPosted: Thu Aug 03, 2017 2:18 am    Post subject: Re: Blown oil hose CJ - connectors? Reply with quote

Harv wrote:
So the pic is you posted is taken looking through the STB side fuselage access panel which makes more sense.

I'm with my aircraft tonight so will take a picture for you.

The only possibly explanation I can think right now is someone has done a very nasty modification with the engine oil feed line to the cooler buy adding a fitting and running two smaller hoses (possibly for ease of replacement??) rather than obtain a new Chinese hose.

It has certainly doubled the failure mode (as you have found out) and I'm quite surprised whoever maintains your AC hasn't insisted this was removed (that's just my 2pence worth) in the normal course of performing the 3 year periodical hose pressure test Shocked but that assumes they "know" these aircraft.


As you know, there's not a great deal of CJ experience in Europe. I'm very keen to have it torn apart totally and a ground up IRAN rebuild but not sure whether that's viable ultimately. As to converting it back to the correct specification, not even sure I'd know where to start....

Edit: Just noticed the picture I posted has rotated itself through 90 degrees, which probably explains the confusion.


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jay-dub



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PostPosted: Thu Aug 03, 2017 4:22 am    Post subject: Re: Blown oil hose CJ - connectors? Reply with quote

The other thing which is a little different, which slipped my mind entirely, is that we have an engine pre-oil system. Potentially the mysterious hoses are something to do with that...

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