Practically Classics Forum

Hi all

I have a query about knowing how tight to tighten up cooling hose clips, so that they do not damage the hose but do not leak.

I have read somewhere that jubilee-type hose clips should be tightened so that the clip is flush with the rubber of the hose, and no tighter. However, this is a fair bit before any stiff resistance is met when tightening, and I have had a couple of clips leak when trying to do it like this.

I ask because I have changed all the hose clips on my modern (10 year old) car for Jubilee clips as several of the original spring-type clips leaked, and so want to make sure that I now don't get leaks but also don't wreak the hoses.

On my Austin Allegro, which has clips with 'two wire-coils', I used to simply tighten them up as hard as I possibly could. I had removed and refitted all the hoses many many times like this without a problem, although I once had a leak when the very end of a hose split (to be fair it was 30 years old!).

Any helpful pointers on how hard to tighten up Jubilee clips?

Regards all, Bolin.

A Lot depends on the quality of the clip, cheap ones will strip the thread before its even tight.
If possible buy the stainless steel ones for under the bonnet.
If your not sure how tight they can go clamp one around a piece of wood and tighten it as far as you can that will then give you an idea of what that brand of clip you have will take.
Its also a lot to do with experience and how it 'feels' to you as you tighten it.
I do like the idea of going until its flush with the hose,seems a reasonable starting point to me.

Tighten 'em a bit until they start to squash the hose, not too much, run the engine, if it doesn't leak then it's tight enough! Handy hint- use a small socket, it's better than a screwdriver, and put a bit of coppergrease on the threads, it will make your life a lot easier next time.

Often on an old engine a brand new hose will leak, seemingly even after tightening it. This can be down to the surfaces of tubes and elbows which do not allow the rubber to bed down. Chief culprits are light alloy castings such as stats and waterpumps - I NOW always examine these before fitting and all traces of corrosion or deposits are dressed with abrasive paper. It is also possible to crush small bore tubes if overtightening which again will give a leak - old style brass rad elbows are also vunerable to damage and an unoticed "dig" from a carelessly applied tool can form a good escape route for the coolant however tight the clip is.
My tip apart from the above, is the same as Mr Rusty - use a good quality socket head worm drive clip (not the cheap ones from Autojumble stands) and final tighten with a socket, a new hose on to a good surafce will seal if the clip is just depressing the rubber. An extra tweak may be necessary if leakage is apparent after warm up - any need to really graunch the clip means it's probably not a hose prob

PS. After replacing all the hoses on my Princess 2200 last year most of them leaked! They all had to come off and I then did it properly

Many thanks for the tips guys.

I had bought a set of genuine Jubilee stainless steel clips, cost a lot but as I want to keep the car for a very long time I saw it as a wise investment, having had problems with rubbish clips before. I didn't bother with copper grease as the stainless shouldn't corrode.

I have tightened then with, erm, a tool that's like a cross between a socket and a screwdriver (can't for the life of me remember what it's called!). I find that ordinary screwdrivers jump out and wreak the head. The seating surfaces are all in fairly good nick.


The hoses are a bit squashed, just enough for the clips to be roughly flush, and as I have no leaks then I'll leave then as they are for now. Only a couple of the clips are tightened to the point where stiff resistance is met, but as there are no leaks at the mo I'll leave them like that.

Bolin wrote: I have tightened then with, erm, a tool that's like a cross between a socket and a screwdriver (can't for the life of me remember what it's called!)

Nut spinner

I never use the OE type wire ones. I don't like the way they bite into the hose.

That screwdriver/socket tool is a good bet for tightening. Normally a 7mm socket will fit, but they are so easily over-tightened and stripped using a socket wrench.