Pneumatic tees for return pipe junctions - is it possible?

[DLM]

I was given a very helpful suggestion a couple of months ago. I was trying to source an alternative for a split return pipe t-piece - and somone suggested 4mm press-in pneumatic fittings as sold by RS Components and others. See thread link below

http://bxclub.co.uk/forum/viewtopic.php ... e42097586.

I used some similar fittings this week when trying to replace a section of octopus - but the fittings didn't take kindly to lhm and leaked.

It's a great shame as it's a good idea, but unfortunately it didn't work in practice. On the other hand, they are pneumatic fittings, not hydraulic ones, and the problems only seem to start once they're wet with lhm.

[ken newbold]

Only thing I've found that works, is more of the same pipe, when scrapping cars, I've usually grabbed as much loose easy to get at pipe as possible for doing just such tasks.

In the case of the octopus, it really isn't that bad a job to fit a new one and they're not that expensive either.

I always reckon on 2 extremely filthy hours.

[AndersDK]

My present runner - born as a 4x4 - has been rebuilt at some stage to lay up all returns/leaks behind the RHS strut sphere top. At first sight it looks a mess, but boy its easy to correct any leak from a rotten hose

Never figured out why Citroen decided for that solution using an "Octopus".
Must have been a cost issue on the assembly line, as there seems no other logic explanations.

Its very easy modding away the octopus. Except you'll need quite a few extra meters of small gauge nylon/plastic piping & rubber hosing.

Pneumatic fittings are not really suited for no (or very low) pressure feeds. The junctions relies on at least some pressure to make the O-rings clamp on the pipe circumference. Thats why the oil leaks out. If the oil was under presuure I believe the pneumatic fittings would be leakproof - provided the O-rings are the usual nitril rubber which will withstand oils of mineral origin and their synthetic counterparts.
Remember though that the maximum working pressure of standard pneumatics is 10-12bar : dont over-use it as a pressure line in your BX

[AlanS]

I don't know if you can get them over there, but here we use connectors for "drip irrigation" systems which are about 3mm IIRC and can be bought at hardware and gardening supplies stores for around 8 - 10 cents each (about 4-5p in your money)
Made from similar plastic to the ones fitted to the T on top of the LHM tank, resist heat and don't seem to mind a dose of LHM.
They come in connectors, Ts and elbows.


Alan S

[DLM]

Good points all: thanks for the comments.

The owner of this has a penchant for making up fittings in copper piping so that's what was eventually fitted with some washer tubing where rubber piping couldn't be avoided. Would normally have fitted a complete octopus but susptect this car may not live beyond its next MOT test.

I'm open to anything to avoid spending £20 plus on single t-pieces !

[jeremy]

Nylon washer 'T' pieces?

[ellevie]

QUOTE slim123 @ http://www.frenchcarforum.co.uk/forum/v ... hp?t=23382
As for the "T" pieces and junctions, if you pop into a motor factors and ask to have a look through a selection box of screenwash pipe junctions, you will find all sorts of goodies to join the pipes with, these are all plastic and will not be affected by LHM.
UNQUOTE

[kiwi]

In the case of the octopus, it really isn't that bad a job to fit a new one and they're not that expensive either.

Not expensive in the UK maybe! I checked out the price in NZ and the reply was $250 which is near enough 100 Quid given the price of them there is more chance of seeing a BX scrapped in NZ than repaired now days.

[DLM]

I'd look carerfully at the alternative plumbing options then - it can be done! Unfortunately, even the best-preserved octopus does rot away in the end.