Silicon Vacuum hose

[onesea]

Any reason it should not be silicon vacuum hose?

 

For a long whilst one of the gremlins in a Triumph Trophies fuelling system has been the vacuum hose.

Traditionally it runs between #3 Carb and the Peticock valve on the fuel tank.

The attachment to the valve is not a great design. Attach hose and straight into 90 Deg turn around frame.

Replacements are available at £25 each after afew years they all go same way perished.

 

This time I have spent afew pounds on a length of 3mm Silicone vacuum hose. Will it stay rigid at temperature?

[Mr Fro]

Yeah, that's one of the handy properties of silicone.

 

The down side is that it swells badly when exposed to fuel or fuel vapour.

[Mississippi Bullfrog]

Get yourself some model aircraft fuel tube. Thick walled silicone that works great as a vacuum hose and won't be affected by fuel.

[Stu]

It wouldn't matter if it stayed rigid or not as once its vacuumed if it collapses then it will stay vacuumed and the fuel tap should stay open anyway 

[Trooper74]

You will need a fluro silicone lined hose for use with petrol.

It will also have to have a steel wire helix embedded between the layers to prevent collapse due to vacuum or have a wall thickness equlivent to the bore for the same reasons.

Very specialist, quite expensive .... 

I can supply it .... but it would be made to order. Minimum 10 metres ....

 

 

Stick with Nitrile ... possibly Viton 

 

[Mickly]

The Trophy Cafe racer I’m working on does away with a vac tap & just has a on / off / res

I’ve blanked off the vac hose.

It’s an option ?

[husoi]

I quite like the stuff from merlin motorsport

 

https://www.merlinmotorsport.co.uk/

 

Not the cheapest but top quality

[Trooper74]

2 hours ago, husoi said:

I quite like the stuff from merlin motorsport

 

https://www.merlinmotorsport.co.uk/

 

Not the cheapest but top quality

Indian quality, but not fuel proof...

[Mississippi Bullfrog]

https://www.sussex-model-centre.co.uk/accessories/engine-accessories/fuel-tubing

 

Used this stuff for years, much better than the usual hose fitted.

[Trooper74]

6 hours ago, Mississippi Bullfrog said:

https://www.sussex-model-centre.co.uk/accessories/engine-accessories/fuel-tubing

 

Used this stuff for years, much better than the usual hose fitted.

Used it with petrol ?? Or methanol ..?

Edited March 17, 2021 by Trooper74

[Mississippi Bullfrog]

2 hours ago, Trooper74 said:

Used it with petrol ?? Or methanol ..?

Both. You can buy fuel tube for glow motors or larger petrol engines.

[fastbob]

This should be interesting then .