I have been bedevilled by poor hose sealing of late. I recently experienced a worm-drive clip that looked tight, felt tight, seemed to be tight when tested with a 7mm socket, but in fact had jammed, so it was not tight. Took me ages to find it as it only started leaking very slightly at just a touch over 12 psi in the system!
So did some research on clips and came up with these little items - rather expensive each - but allegedly good for huge pressures in turbo boosted applications etc etc, as used in space, as used by World Rally Championship teams, tested in Death Valley etc etc!

They are Murray Constant tension clips, Pics attached. https://www.murraycorp.com/clamp/con...al-clamps-tss/
As you can see they have a double ridged inner, and a separate outer that looks like a normal worm drive clip, except that it is convoluted, so when it is tightened, the outer is sprung loaded to take care of any expansion and contraction and "give" in the hose and spigot. I trust that these may put an end to the troublesome weeps from the crossipe/waterpump/lower radiator hose joins that on my car seem to require retensioning quite often. Not put on the car yet, but here in France we I have a minimum of 3 months lockdown, so plenty of time!

 

Interesting. They look very robust.

Cheapo clamps can be a real headache. There are a number of really good clamp designs out there but they'll usually have to be special ordered. The local neighborhood parts supply usually won't have 'em because they're too expensive

Cheers
DD

 

Greg you mention a regular leak from the bottom radiator hose. Is this common as I have a leak in that area but feared it may be the rad?

 

Brinny
In my opinion the bottom hose is the worst bit of design and execution on the car. First of all the ends should be the same diameter - which they could be but are not because the spigots are not and they should be. Second the shape is not sufficiently moulded to ensure no rubbing against the engine; third the hose clips on both ends are hard to access; fourth the cross pipe to pump spigot is a piece of junk and not properly round. etc etc /rant over.
Right now I have top quality Mikalor T bar clips on the hose both ends, and these are Ok but need tightening very frequently, at least every 6 months. I am hoping that these new clips will prevent leaks and render regular tightening unnecessary. We shall see.
Leaks are common in the entire HE system, usually shown by annoying coolant loss, mainly as a result of leaks under pressure when hot from the many pipes. The hoses at the bottom of the rad, particularly the heater return hose, can leak a bit, ditto the main hose and ditto the other end of the bottom hoses where it joins the water pump inlet.
In the end I bought myself a radiator pressure testing kit, which is the best thing I have bought since OB's mains impact gun! It was this that enabled me to find my latest leak - which was the B bank top hose clip that had jammed and seemed tight, and only wept at 12 psi or above. These reliably in a couple of minutes show all leaks and will tell you whether it is the rad or the hoses, eg:
https://www.ebay.co.uk/p/1354129720?iid=253740152138
I did float the idea on the forum of getting Viper performance to make us a run of bottom hoses from their guaranteed for life kevlar stuff, but nobody was interested in anteing up for the tooling etc. But entire area is something I am going to think about sorting out something better.

 

WHAT! Theres a company that will do high end hoses for the car we just have to bribe them??

 

The Murray clips are excellent, especially on applications with plastic pipe joints as used on newer vehicles to maintain constant tension. Oetiker clips are also good for maintaining constant tension across various temperature ranges.

 

For a while I had a special cupro-nickel bendable convoluted metal hose between the rad and the pump, and had Viper Performance make me a reducer from their kevlar/nomex stuff for the water pump end, with a normal hose piece to join the other end. It worked really well. I discussed with them the cost of a kevlar entire hose, with a decent reducer built into the thing, and shaped so that it did not hit or touch anything. (Quite how I would send them that shape I am not certain, but I am sure it could be done). The real cost is making the tool (ie the former for the hose) and this we would have to pay for as a one-off. Thereafter the hoses would be at normal cost.
From their website:
https://www.viperperformance.co.uk/p...ium-pipes.html

NOMEX reinforced hoses

NOMEX (aramid) is ideal for high working temperatures and higher pressure.
Particularly well suited for turbo / boost applications.
Working temperatures from -50 °C to +220°C , peaking at +240°C

Nomex reinforced hoses are NOT suitable for oil or fuel.
Ideal for:

• Water
• Air
• Coolants
• Turbo boost
• High temperatures
• Higher pressures
• Small amounts of oil mist.

 

I know i'm probably on my own in thinking this but i've always quite liked this style of spring hose clip:
https://www.banggood.com/100Pcs-10-S...r_warehouse=CN
Super fast to fit, Easy to remove so long as you have the correct tool (angled long nose pliers usually), keep tension for 20+ years as seen in all the 1990's Toyotas that still run perfectly.

 

[QUOTE=Greg in France;2211049]Brinny
In my opinion the bottom hose is the worst bit of design and execution on the car. First of all the ends should be the same diameter - which they could be but are not because the spigots are not and they should be. Second the shape is not sufficiently moulded to ensure no rubbing against the engine; third the hose clips on both ends are hard to access; fourth the cross pipe to pump spigot is a piece of junk and not properly round. etc etc /rant over.
Right now I have top quality Mikalor T bar clips on the hose both ends, and these are Ok but need tightening very frequently, at least every 6 months. I am hoping that these new clips will prevent leaks and render regular tightening unnecessary. We shall see.
Leaks are common in the entire HE system, usually shown by annoying coolant loss, mainly as a result of leaks under pressure when hot from the many pipes. The hoses at the bottom of the rad, particularly the heater return hose, can leak a bit, ditto the main hose and ditto the other end of the bottom hoses where it joins the water pump inlet.
In the end I bought myself a radiator pressure testing kit, which is the best thing I have bought since OB's mains impact gun! It was this that enabled me to find my latest leak - which was the B bank top hose clip that had jammed and seemed tight, and only wept at 12 psi or above. These reliably in a couple of minutes show all leaks and will tell you whether it is the rad or the

Where do you connect to when you test greg?

 

[QUOTE=brinny;2212211]The kits have a selection of caps, just place the cap onto the crosspipe spout or the header tank, connect the pump to it and pump. You will hear the hiss or see the fluid running out.