flap inside of oil hose

[chewton]

upon inspecting oil cooler hose befor instalation their is a small flap of ruber about 1/4'' long at end of hose and start of fitting on inside . is this a bad hose ?or can it be fixed, or is it ok to use? bob mcmillin RV-9 90825 FF.

[akarmy]

There was an inspection requirement for this type of problem with the hoses from Vans about a year ago I think. If you can get it out of there you should be fine, however if not then you need a new end termination which may mean a new hose depending on length requirements.

[robertahegy]

That does not sound very good. The last thing you want is your oil supply impeded by some rubber hose unraveling. I assume you are using some type of screw together reusable type hose fittings. Bite the bullet and by some new hose and try again.

JMHO

Roberta

[tacchi88]

Miss Roberta,
If a hose has any indication such as you describe, do indeed get rid of it, no exception. For whatever reason, what ever flows through the hose will keep on leaking internally throughout the walls of the hose. Pressure can actually "bubble" up the inside and actually block flow, and still looking good on the outside, and even pass a flex test. Had it happen on a hydraulic brake line causing the brakes to lock without warning. It generally can happen when the hose is assembled, though rare, or with age.
T88

[deene]

This is a common problem that can occur during the installation of the end fitting onto the hose (inner part of fitting shears flap during attachment). Return the hose for a new one or if you have excess hose, have a mechanic (or other expert) remove the fitting, cut the bad end of the hose off and reinstall the fitting.

The installation of the end fittings is not a big job, but does require the use of special mandrels and some careful work and inspection. Not for the novice without supervision...

BTW, the above applies to most but not all aircraft hoses as some do not have removeable end fittings. Be sure to inspect all hoses before installation...

Also, if you live in an area where your have mud dabber wasps, keep all ports, hoses, and holes covered with tape until the systems are closed out.

Deene

[Highflight]

Actually, this is a subject of a Service Bulletin posted on the Vans website a few years ago.

http://www.vansaircraft.com/pdf/sb02-12-1.pdf

The bulletin makes it seem that this problem was the result of a particular run of hoses so it would be disappointing if the same problem is to show up again.

Perhaps your hoses have been sitting around quite a while and may be part of that original bulletin?