Hose clamp tightness

[Dave R.]

This may seem like a very basic question but, I am rather new to the mechanical side of collector car ownership. I recently installed a reproduction upper radiator hose and the repro Wittek clamps. How tight should I tighten these clamps? I am afraid of damaging the new hose by tightening it too much but I also don't want it to leak.
I am in the process of changing my anti-freeze and, after running the engine with the radiator flush, I noticed that there was some minor leaking / bubbling and one end of the hose. Stupid question; should I tighten the hose more or is there something else going on?

Please bear with me; I'm new to this game.

Thanks, Dave

[Duke W.]

Re: Hose clamp tightness

Remove the hose and check both the hose and nipple for exfoliation, pitting, material transfer to the hose and nipple roundness.

Only tighten the clamps enough to prevent leaks. I would call this snug, not tight. Inspect after some heat cycles and tighten any that show evidence of leakage. Overtightening can damage the hose and distort nipples. I also use a thin (emphasize THIN) film of silicone grease on hoses where they contact nipples. This helps seal and will prevent the hose from seizing onto the nipple.

Make sure you thoroughly flush the system to remove all traces of the flushing chemicals.

Use Zerex G-05 antifreeze. Research the archives using key words HOAT, OAT, and IAT to understand why Zerex G-05 is best for vintage cars than originally had "green".

The archives will explain what those acronyms mean.

Duke

[Joe L.]

Re: Hose clamp tightness

Dave-----

The best plan: tighten the hose clamps to the torque value for the particular hose clamp shown in the AIM. If there are any leaks, tighten further, as necessary, to quell the leak.

[Terry M.]

Re: Hose clamp tightness

The original Wittek tower clamps used a screw that was designed by the manufacturer to sheer when max torque was reached. Unfortunately the reproductions use a larger screw (detectable by astute judges) which will exceed the torque limits. this IS a case where size really matters.

[Alan Drake]

Re: Careful on tightness!

I purchased date coded Wittek clamps - installed one on the lower hose, noticed it leaked just a drop (one per hour) and a pain to find.
When I removed the water, clamp, hose, and a few more items to get at it the problem became known. When I tighted the clamp the screw went through the bottom, thourgh the hose and marked up the water pump. Understand others make some good strong Wittek, however not date coded. Just be careful! An old trick is to put some (not much) Indian Head gasket shellac compound (brown stuff)that can still be found in a 2Oz bottle. Don't let is show.

[Terry F.]

Re: Hose clamp tightness

Consider a very thin coat of sealent on the inside of the hose before clamping it together. Let it sit a couple days before filling. It will not leak. Terry

[Keith M.]

Re: Hose clamp tightness *NM*