Rob; wasn’t avoiding the question,
just hadn’t gotten to it. But also don’t have “the”
answer because it is too general – different clamps, different sizes, different
hose materials, different applications. Probably the main difference in
application is the pressure you expect it to hold. Rely on your good judgement.
I’d say in general for cooling
system applications, you tighten the clamp about as tight as you can make it
with a one hand on good size screw driver (how’s that for precise);
squeeze the hose some, but not to damage it. The torque will be in the range
of maybe 10 to 30 inch-lbs. Then make sure it doesn’t leak under the
pressure you want it to hold.
On my cooling system I have reinforced silicone compound
hoses (blue stuff from McMaster-Carr). My system is set up with dual caps in
series with the potential of 38 psi max pressure. I put the hoses on, tightened
them to what seemed right, then pressurized to system to 38 psi. A couple of
the connections leaked, so I got my ¼” drive ratchet with the appropriate
socket, and tightened the clamp until the leak stopped. I’m guessing it
was about 30 – 35 inch lbs. I checked them a few weeks later and found I
could give most of them another partial turn to about the same torque level. Haven’t
touched them in the year of flying since, and there have been no leaks, and the
hoses still look as good as when they went on. I’ll probably replace
most of them within the next year - just because.
Al