Hose clips???

[scopeusa]

I have been off the radar for a while sorting some legal stuff but have been wanting to address my rusty constant pressure hose clip issues. I was considering a number of options and have hunted high and low. primochill.com have a steel offering which may suit some applications at 89 cents a pop. (see link)

http://www.primochill.com/?post_type=product&s=steel+spring+clamp

The problem with these is you need to separate the hose connections to slide them on not so easy at the bottom of the engine right at the back. You can get a similar clip from Norma

http://www.normagroup.com/norma.nsf/id/Products_EN

Then there are the Breeze SS constant pressure clamps which backed off all the way would alloy your to open it and fit it around the hose with the pipe still connected.

http://www.breezehoseclamps.com/breeze/constant-torque/

I then stumbled across these again at priomchill.com said to be good for pressures up to 200 PSI an open clip with double ratchet teeth available in 3/8, 1/2, 5/8, 3/4 and 1" in different colors. Operating temp 225F with occasional peak at 340F. No rust problems here.

Any thoughts anyone???

 

[jcyamaharider]

Any of these maybe another option.

http://www.mcmaster.com/#standard-hose-clamps/=118ly1u

 

[tdonoughue]

I would question a 200 psi rating on any clamp. Looks like most of the metal bands measure their strength in in.-lbs., not psi. If the clamp is purporting to hold in that much pressure, on a line, that would seem to also depend upon the type of connection you had and the materials used in both the hose and the mating, in addition to the clamping strength. Most of the places I see them sold are for fish tanks, which is a far lower strength requirement and a far less critical application (your fish tank won't sink if it fails).

So, it is intriguing. But I would want more research on its strength before slapping it on my boat. IMHO.

 

[scopeusa]

Thanks for the heads up to McMaster.com they certainly have a wide selection and decent prices of both types. I thought about buying some plastic ones and putting them on decent reinforced plastic pipe and connecting them to an air tank at 150 PSI and leaving them for a week to see what happens. I am not expecting them to stand up to 200 PSI I cannot think that the cooling water pressure runs at anything like 150 PSI, if it does by the looks of some of mine I should have sunk by now. Everything that tdonoughe says is well thought out and makes a great deal of sense, but as he says intriguing.

 

[tdonoughue]

So, let's brainstorm here a bit:

If you were going to test one of these clamps somewhere in the engine that would subject it to the highest pressure of a clamped hose, but hopefully something not too tragic (e.g. if it blew, you would not sink (I know--the boat won't sink anyway, but like, let's not ruin the engine)), where would you put one or a set to try them out?

 

[Gym]

Thanks for the heads up to McMaster.com they certainly have a wide selection and decent prices of both types. I thought about buying some plastic ones and putting them on decent reinforced plastic pipe and connecting them to an air tank at 150 PSI and leaving them for a week to see what happens. I am not expecting them to stand up to 200 PSI I cannot think that the cooling water pressure runs at anything like 150 PSI, if it does by the looks of some of mine I should have sunk by now. Everything that tdonoughe says is well thought out and makes a great deal of sense, but as he says intriguing.

You won't see pressures anywhere near that in an open system. What you will see is shock and vibration. I would be concerned with plastic clamps in that environment. Stainless all the way for me.

 

[robert843]

I think it could be great to keep on board as a quick emergency back up. Better then what I have now it could easily be changed out.

 

[scopeusa]

The first thing I am going to do is purchase some from a couple of different outlets to see if I am buying different product from different manufacturers. I will conduct my own series of pressure tests on suitable hose and connections. I will then see how much force the clamp will withstand from pulling and twisting on the pipe with the clamp off the pipe and then with the clip installed. Whilst not conducted under test lab conditions it will give me a degree of confidence. I a not worried about vibration. One place I would install, given the chance today, would be the tell tale hoses that pump the water out to show the engines have cooling water circulated.

 

[scopeusa]

Well the plastic clamps finally arrived and I tested one at around 18 mm on a standard barbed airline quick disconnect. It was a rubber airline and was a loose fit on the pipe, you could remove one from the other with just your thumb and forefinger. I used the same constant pressure tool from Draper to tighten the plastic clamp working in reverse. The upshot is that I applied air pressure at 130 PSI and the hose stayed in place for a week before I pulled it apart. No it did not grip as tight as a screw clamp but I think it is pretty close to the standard constant pressure clamp when squeezed. I have no worries about using these on any of the engine bay water system pipes. I can also just use the Draper tool to loosen the old clamp and slide it down the pipe and then open the new clamp fully pass it over the pipe and tighten. The old clip can hang on the pipe but this allows you to replace the clip without pulling the pipe off the connector and at the back and bottom of the engine bay that's a huge reduction in four letter words. Bye bye corrosion.