With the recent below zero F weather and having replaced both the radiator and all hoses last fall, I found myself dealing with coolant leaks again on the 1" radiator hoses. Also switched from the Evans coolant to 60% dexcool.
After much observation, diddling, studying, it appears the problem is caused by component shrinkage due to extreme cold and since the hose clamps don't change, allows a leak to occur as the other components shrink with the cold. While I found it is entirely possible to (experimentally) eliminate the drips by overtightening the clamps that is not an option I care to practice as the hose can be damaged from such things.
The local Fastenal store catalogs constant pressure clamps similar to what Darinh mentioned that he got from Mcmasters. Got 10 of them today. Attached is a photo of the CP clamp and standard clamp for comparison. The manufacturer is Ideal (same as who manufactures standard clamps) described as #16 ( for 1") Series 47 - 13/16" to 1 1/2" HD Constant pressure hose clamp. As the photo shows, they have 6 belville washers and a smaller flat washer at the end. Tightening compresses the belville washers which allows for automatic adjustments with temperature changes, I was really looking for some spring clamps like the ones Rotax uses on the small cylinder head hoses but could not fnd anything the right size. A Spring clamp is also a constant pressure clamp but should be cheaper (if one does not buy it from rotax) - but no joy. On the Ideal Constant Pressure Clamps the band is 9/16" wide so a little wider than a standard clamp. The band also has an entirely smooth inside surface so the hose does not end up getting shredded by the spiral slots.
They are a little pricey - $7 each with tax.
Don't have then installed yet but hope to get out to the hangar real soon.
Dave S
Kitfox 7 Trigear
912ULS Warp Drive