Coolant hose clamps

If all those clamps leak then you have other problems. Dried coolant creates deposits and there are likely some between the hose and what it connects to. Also check the metal where the hose connects to make sure that it is not pitted. Since you are going to have to drain some coolant I would consider replacing the hoses.

 

All clamps will "weep" when exposed to extremes in temperature the clamps expand at a different rate than the cast that they are clamping the hose to. The clamp will stretch a small amount with repeated temp changes. Using a quality clamp will reduce the effects but it is just preventative maintenance to tighten your clamps once or twice a year when the engine is stone cold.
Using emery cloth on your fittings when you have a hose off to clean deposits including micro bits of rubber also helps to reduce weeping leaks.

 

I can't tell if your clamps have the springs to keep constant tension. Almost everytime I change hoses/clamps I have to retighten after a few days and usually again when the cold weather comes. Try a different type of hose. Good luck

 

I’ve found retightening them when hot, works best. If they’re silicone hoses, they’ll seep for a while, especially when cold, till the hose gets “glued” to the metal. I’ve never tried it, but often thought about a thin layer of permatex #2 on the metal before putting the hose on. Might help initial seal. I wouldn’t use the clamps pictured. Those are missing the spring needed to be considered constant torque clamps. Use the good constant clamps made for silicone hoses. Must be large enough for the inner ring to completely wrap the hose, then be tightened and re tightened as needed while good and hot. Eventually the leak should seal up. The smaller the clamp, the harder to get tight enough, because of the full wrap design. Go easy little at a time, to avoid stripping the threads.

 

Have any pics of the clamp placement?
That can have a effect on the sealing of the hose.

 

Might be worth looking into clamp tite tools.
Some places you just can’t get them on.

 

We’ve always used this to help tack coolant hoses on nipples and on bolt threads that their threaded holes are tapped and open to a water jacket/passage.