Brake Reservoir Vent Line Replacement

[KNS]

On my "84 Carrera there is a rubber vent line coming off the brake fluid reservoir and eventually connects to plastic hard line that runs outside/underneath the car.

The line is hard and needs replacement. it is 4.0 X 1.5 mm. None of my local FLAPS have a comparable size and Pelican says the bulk hose is NLA.

Is this line under pressure? Can I use fuel line or what else would be recommended?

Thanks

[Solamar]

Try Belmetric -

https://belmetric.com/hose/brake-fluid/

They are very DIY friendly and will sell by the ft.

[KNS]

I'd heard about Belmetric and completely forgot - thanks!!

Edit, they don't have it in a rubber line, only polyamide. I don't know how that would fit over the reservoir nipple.

[917_Langheck]

The hose is open to air. The only thing it has to do is keep excess fluid off your paint. Any appropriate hose will do (withstand brake fluid and is 1.5 mm id [is it really 1.5mm id? Another thing I need to check into my mental database]). You can always use a small clamp for cinching down a slightly larger ID hose.

https://www.mcmaster.com/epdm-rubber-hose/

https://www.mcmaster.com/epdm-rubber-hose/id~2mm/

[Solamar]

On my 78, it's fabric coated line off the res, then becomes polyamide at the fender. Pretty sure I bought the fabric hose from bellmetric.

I found the S turn behind the res was critically important to keep the fluid from escaping on hard right turns (track).

Hopefully in this pic you can see the transition to poly at the fender bolt line.



Here's where the poly line exits (above and forward from the battery)

[Solamar]

Originally Posted by 917_Langheck

Any appropriate hose will do (withstand brake fluid and is 1.5 mm id [is it really 1.5mm id? Another thing I need to check into my mental database]).

I learned when I redid my car that Porsche PET lists hose sizing in an odd way.

IIRC it's 4mm ID with a 1.5mm wall (7mm OD).

[fintstone]

Do a search for N023531. That is what I used on my '74. 3.5/7.5MM.

Some sell it by a fixed length and others by the foot or meter. It is used as vacuum line on a lot of European cars including VW. It looks/works like the original IMHO.

[KNS]

Originally Posted by Solamar

I learned when I redid my car that Porsche PET lists hose sizing in an odd way.

IIRC it's 4mm ID with a 1.5mm wall (7mm OD).

Thanks for posting - that makes sense!

[fintstone]

This is what the part number I posted above looks like.