Beware of hose clamps

[Buick35]

I thought I'd connect my under dash heater box on my 35 Buick,I really won t need it but I was bored. Anyway I bought the correct heater hoses,bracket and clamps(the tower type) probably made in China.I hooked every thing up and filled it with water and noticed a leak which I thought was my heater core. Today I took a better look and found out the upper clamp going into the box wouldn't tighten down correctly.I replaced it with a worm type now all is good(knock on wood).Greg

[Grimy]

I learned a long time ago that correct-type clamps aren't good for leak-free performance when installing new hose--could be the current rubber formulation, I don't know.  I put the correct clamps in the center of the hose snugged up just enough so they won't flop around, then use worm clamps on the business ends for the initial installation.  After 20 or so heating-cooling cycles, the hoses have bonded, more or less, to the pipes.  Then I unscrew the worm clamps all the way to create a gap, an incomplete circle, that will clear the hose, slide the OEM-type clamps down to the sealing point and tighten.  I've had almost no luck reshaping OEM-style clamps so that they work properly if I've stretched them to go over the closed hose--and that's why they go in the middle before connecting the ends of the hose to the pipes.

[Terry Bond]

That's a great technique. Works like a champ everytime.

Terry

 

[Gary_Ash]

There are reasons why worm-drive hose clamps are now universally used and the other types have mostly disappeared.  Spring wire clamps are used by OEMs because they are very cheap and OEMs can afford the special tools to install them.

[zepher]

Not only are spring clamps cheap, they are quicker to install and they keep constant tension on the hose so even as the rubber shrinks the clamp still maintains maximum clamping pressure.

I don't like spring clamps but every car manufacture uses them so I purchased the tool needed to properly remove them and reinstall them.

 

As for the tower clamps, Grimy's trick works like a charm.

[Bloo]

The typical worm type clamps found in the parts stores do not have a round cross section, and are begging for a leak because they don't push on the hose in anything even close to a perfect circle. NEVER use them on fuel.

 

Those US-style worm clamps were pretty stout in the old days, but I remember in the 1990s they got so cheap and soft you couldn't even tighten them without stripping. If they survived tightening there were instances where, after about a week they would go "TINK!" and the tab would just fall out of the worm. They are a little better now but lets face it, it's a bad design because the clamping surface isn't round. They also extrude the rubber through the worm slots. Almost anything else is better. Look for a round clamping surface. A little more width is better within reason. Wire clamps tend to dig into the hose more than I would like, but at least they are round.

 

 

 

 

[zepher]

Stainless worm clamps designed for use on silicone hoses will not eat into the hose and extrude rubber through the slots because they have a band under the worm portion.

These clamps are far superior to the normal worm gear clamps.