Silicone hoses clamp loosen up

[glasgow]

Noticed today the mikalor clamps of most of my silicone hoses are loose. I upgraded to silicone hoses 3 years ago. In the first few weeks after installing them  I checked the clamps and re-tightened them a couple of times but never checked them again for over two years.

Is it the mikalor loosen up by time because of the vibration and heat? or the silicone hose gets "thinner"?

- is this one of the side effect of silicone hoses or I never tightened them enough 3 years ago?

- how often would you check the clamps? Any recommended torque please?

Thank you

Ahmed

[SM25T]

I think the silicone must expand in each heat cycle .... then contract. I check mine every month or so .... they all tighten a turn or so. Don't miss any .... as the one you can't get access to win be the one that drains the system. Been there.

[SM25T]

I use a socket on a 1/4" drive ratchet ... and do them up tight ... with the short handle of this ratchet. You get much more torque than with a screwdriver ..... but not enough to strip the thread.

[Jonathan Kay]

What SM25T says: little and often. But i wouldn't worry at all about what you discovered.

Note that point about the socket. Most clamps can be done up with a screwdriver or a socket tool. Using a screwdriver is notorious for slipping off and spearing it into the next available object, whether man-based or man-made.

I do mine up less tight: screwdriver handle and wrist tight. But I do put a bit of silicone lubricant on the thread and where the band clamps the hose.

Jonathan

[elie boone]

Despite they look good it is difficult to obtain a good seal so i don't use them, a normal SS hose clip works so much better. However on a fuel hose i do use a Mikalor style hose clip but then simply zinc plated.

[glasgow]

Agree, they look of a good quality metal and they are expensive but don't do a good grip and have a narrow working diameter. Should look for something else.

[DJ.]

Using zinc plated jubilee clips on the Caterham silicone hoses, I've found that they need tightening over the first couple of weeks, but then stay tight after that. It seems that a few heat cycles is enough and then they stabilize. I use the socket technique with 1/4" ratchet, but only use two fingers to tighten.

[Martin J]

Are silicon hoses really worth the extra expense over standard ones? Apart from being available in a range of colours what are the advantages. 

Standard nine year old & 30plus k miles hoses on my caterham from when I built it. They still look perfect & I never have to tighten any jubiliee clips.

[Jonathan Kay]

For our sort of applications I think the only relevant differences in practice are looks and longevity.

Jonathan

[7 wonders of the world]

9 years out of CC OE hoses................

 

After just 6 months mine were shot, total carp surface cracking all over on all of them, god knows who made them but they were truly shocking quality,

Quick phone call to Lee @ SFS sorted the problem though.

 

 

[DJ.]

Silicone hoses were standard on my kit in 2011, I wouldn't have paid extra for them

[glasgow]

One of the reasons for using silicone hoses is they can easily be remove and re-install when doing modifications in the car, but on the expense of they don't provide a tight fit

[Martin J]

My hoses must be a lot better than yours were Seven wonders. 6 months life is rubbish.

I'm not aware mainstream car makers fit silicone hoses & do we hear of tin tops suffering regular hose failures?

I think sometimes it's easy to become paranoid about our little cars.