Correct hose clamping and firesheathing

[BillLipson]

I am currently completing the 5 year rubber replacement on my 912 ULS / VG Savannah.

 

Rotax and other aviation sites seem to recommend using the Oetiker brand stainless clamps for fuel and oil lines but they seem to be very hard to obtain locally (Qld). Does anyone know of a good supplier?  Alternatively what other types of clamps are owners using? 

 

My engine does not have any fire sheathing on oil/fuel lines and will add this as hoses are replaced. Can anyone recommend a good supplier? Thanks for your thoughts.

[AndyDrain]

Hi Bill

Interested in your progress as it is a task I am currently planning for on an S.

I source quite a few things from RS (https://nz.rs-online.com/web/c/fasteners-fixings/clips-springs/hose-clips-jubilee-clips/?applied-dimensions=4291630177)

 

This is an NZ link but the company is global. I have always found them good.  Although these days they charge postage. ( I used to be able to order  couple of components which they would ship from the UK for free.)

 

Are you planning their crimp type clamps ?

 

Do you have the ICP corrugated pipes ? These just have a short section of rubber at each end. In the case of my oil lines this appears to be hydraulic hose.

 

Andy

[409tonner]

Hi Bill try this site out for your fire sleeve not sure on price as I just seen this pop up on linkedin
https://www.convoluted.com.au/catalogues/

[BillLipson]

Hi Andy and 409tonner

Thanks so much for your replies. The group you recommended 409 (Convoluted) were great and I have ordered the fire sheathing at almost a third the cost quoted to me by a Brisbane based aviation part supplier. After a lot of searching was also able to find a group in WA who were very service orientated and able to supply all the Oetiker clamps + clamping tool I needed  (autopartswholesalers.com.au)I am using the single ear stainless clamps as recommended in the excellent two part article in the Rotax Owner forum (Rotax 5 year rubber replacent; My Savannah uses all rubber fuel and oil hoses. 

[Area-51]

DCI, Diver Consolidated Industries, in Victoria for all OE ISO standard thermal and acoustic protectives.

 

Uniclamp Australia, Ron 1300 027 886 for NORMA style hose clamps.

 

Buy complete kit with pliers and additional packs of sizes marked in pics if undertaking complete 5 year hose change. You will need CLR-922235 23.0mm-24.5mm size clamps as well.

 

OIL Hoses - ENZED HYDRAULICS

Parker 7212 Jiffy Push-On 13mm ID

Parker 7212 Jiffy Push-On 16mm ID

Parker Push-Lok Plus 836-12-BLK

 

FUEL Hoses - REPCO

Gates Barricade 4219BF Greenshield

4219-5653, 3/8" ID

4219-5652, 5/16" ID

 

[skippydiesel]

Check out my input to this Form - Aircraft general Discussion -Constant Pressure Spring Clamp

[Area-51]

5 hours ago, skippydiesel said:

Check out my input to this Form - Aircraft general Discussion -Constant Pressure Spring Clamp

The person asking the question requires "Oetika" type clamps.

 

CLR range of Uniclamps are reusable, simple to tighten and release without slicing your hands open on ears and tags, and maintain constant pressure; set and forget.

 

All those style clamps you have directed readers to are superseded, insufficient, and great as a last resort or where the task is not critical such as washing machines, garden hoses, and Morris Minors.

[skippydiesel]

57 minutes ago, Area-51 said:

The person asking the question requires "Oetika" type clamps.

 

CLR range of Uniclamps are reusable, simple to tighten and release without slicing your hands open on ears and tags, and maintain constant pressure; set and forget.

 

All those style clamps you have directed readers to are superseded, insufficient, and great as a last resort or where the task is not critical such as washing machines, garden hoses, and Morris Minors.

No offence intended or taken (despite your put down) Aera-51 but BillLipson just may be interested to know what cost effective options (to Oetiker) are available in Australia.  Oetika are not so easy to find & there are quite a few  viable alternatives.

 

I have brand new Rotax 912ULS (just turned over 25 hrs today) - it didn't come with "Oetiker" style hose clamps - it came with Constant Tension Spring Clamps (CTSC), which are actually constant pressure, unlike Oetiker's.

 

CTSC are pretty much universal, on recent  automotive/machinery offerings.

 

I have offered two web sites for CTSC here in Australia.

 

Do your recommended  oil hoses meet Rotax specifications ?

 

Gates fuel & coolant hoses sizes can be expressed in metric (we live in Australia)

 

 

[Area-51]

Thanks, that's great, not offended by your response skippy; provided reasons why those clamps you recommended are obsolete based upon nearly 40 years working in the field and what the end results are, but in the right application they are fantastic; use them and enjoy...

 

Personally I wouldn't use any replacement components on my own engines unless they match or exceed OEM manufacturer standards... couldn't care less if it was rotax or any other superduper producer, i'm quality and standards driven, not price driven.

 

People need to accept responsibility to either invest in themselves and do the research first, or just go get their stuff from floods and be happy. 
 

Not everyone has the same level of experience and abilities; not afraid to say something is crap if it is proven to be crap.

 

Conditions are great this morning, taking my hoses and clamps up into the sky!

[skippydiesel]

Heading to the strip shortly

[aro]

My understanding is that the coolant hose clamps need to be spring type.

 

The aluminium expands and contracts more with heat than steel, and a steel clamp without springiness will damage the rubber and eventually leak.

[facthunter]

The expansion on such diameters wouldn't be much at say 110 degreesC. Be lucky to be .004".(.1 mm)  and it's only the ones at the head outlets get that hot.  Nev

[aro]

 

 

1 hour ago, facthunter said:

Be lucky to be .004".(.1 mm)

It doesn't take much to leak.

 

If the clamp doesn't expand, when the engine gets hot the rubber is compressed inside the clamp and you are relying on the resilience of the rubber to return to it's former size as it cools and maintain the seal. Over many cycles the rubber doesn't return perfectly to the original size and can leak.

 

With a spring clamp, the clamp expands when the engine gets hot, the rubber stretches, and the clamp helps the rubber return to the original diameter and maintain the seal when it cools.

 

At least that's how it was explained to me when I had a problem with a hose leaking when cold.

 

[facthunter]

It really is a very small amount. I'm sceptical and the pressure cap can put a bit of force on the join, and you have vibration involved which is pretty damaging Aircraft  engine mounts don't usually all the movement that cars do  Normal clamps do require a periodic small tighten at ;east in the early use period. That's probably  WHY the large adaptation of the spring clip. (to cut servicing).  Nev