Hose clamp question

[Charles in SC]

Is there a torque spec for these things? I have just spent some time replacing a lot of the rubber hoses on the cooling system. I just kind of tighten them till it scares me to go any more. It would be nice to know if there is a right way.
Thanks for any advice!

[gus]

I'm sure there are specs but I've never used them. A good rule of thumb is to tighten until the hose can't be moved by hand on the connection. However, some connections are so tight that they can't be moved even without a clamp so that doesn't always work.

I go by what I'm tightening over. Sometimes the hose may be on plastic or thin Alor brass which calls for a delicate tightening. Most bus connections are pretty tough though so probably won't be a problem. Some are even cast steel, plenty tough.

One thing to remember is that they need to be retightened after a short time in use because the rubber will give (set) and loosen the clamp. This may not be true for silicone hoses which I've never used, but is true for rubber.

[luvrbus]

Charles, I use what the plumbers call a no hub torque wrench it is pre set and can be purchased at any large plumbing supply like Ferguson for around $20.00 has 90 degree and a straight head will not strip a clamp     good luck

[Charles in SC]

Gus, thanks for the thoughts. I was not worried about hurting the fittings, they are brass castings about 3/16 thick. I just wanted to get them as tight as possible without stripping the clamp.

[gg04]

Just change to the spring loaded constant torq..on the bus and on my turboed toad...

[Charles in SC]

Thanks luvrbus, I will look into that, there is a Ferguson's about a mile or so from me.

[junkman42]

Charles, a good rule of thumb is to tighten the clamp until the clamp sinks into the hose about a depth equal to the thickness of the clamp band material.  A light coat of 3M weather strip adhesive in the inside of the hose also promotes long leak free hose connections.  Do not use the adhesive on fuel or oil lines.  If you have to tighten the clamp until the hose bulges to effect a leak free joint You should check the condition of the metal surface that mates to the hose.  My two cents.  John

[luvrbus]

Charles don't hold me to the $20.00 I checked and mine 4 years old now    

good luck

[gus]

What is a spring loaded constant torque clamp?

[luvrbus]

A $10.00 clamp that keeps the same amount of tension  hot or cold and recommened for slicone hoses   

good luck

[Charles in SC]

Gus, I think that is the type of clamp that is generally used on turbo system hose connections. There is a nut that tightens against a spring, and the spring holds the pressure on the clamp. They are very well made and cost several times what a regular hose clamp is.
Hope that makes since.

[NJT 5573]

Its not a big deal on a truck, if you have a leak you can smell it. Different with a coach. I like to double clamp everything that has enough room for two clamps.

[kyle4501]

Here is what a Constant-Tension T-Bolt Hose Clamp looks like.

McMaster Carr has them
http://www.mcmaster.com/

[TomC]

At Freightliner, we use Gates Blue Stripe hoses, that are a good alternative to silicone.  While silicone hoses are supposed to last a lifetime, they need to be retightened several time and can cold weather leak more then others.  I replaced my 5/8" heater hoses on my truck a few years ago with Gates Blue Stripe, installed them once and yet to have to retighten them.  On buses, some of the hoses are in such wonderful places, you don't want to have to retighten them down the road.  Good Luck, TomC

[Sammy]

I use these clamps sometimes.......http://www.oetiker.com/content.asp?l=4&idNavig=88