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Weep vs non weep guns

mac

Well-known member
In the warmer parts of the country below the frost line, a lot of operators use non weep guns. Some don't even know there is a difference. If you want a good demonstration of why you should use weep guns, try this on a non weep gun. Turn the bay on a high pressure function and just let it run for about a minute. Then try to touch the pump head. Be very cautious. I did this for a customer yesterday, and you could have cooked an egg on the thing. It's pretty common for a customer to finish a wash, just hang up the gun, and drive off with time left.
 
I never really thought of it like that. Great point! I try and tell everyone to press the stop button when they are done, but very few people do it.
 
One of my biggest pet peeves is when people leave the spray gun on when not in use!!!

Once in awhile my employees do this. I fire them on the spot!


Just kidding.:)
 
Mac that is an interesting point. What temperature does the head have to reach before it starts damaging the pump? I was always told the only reason for weep guns was the freezing. I am in So Calif. it is suppose to be 103 at my office today lol I don't get a lot of requests for non weep guns. I am sure on hot days like today would compound the heat factor for the pump.
 
This is from the Cat web site: "Operation above 130 F is permissible, however, additional precautions should be taken to protect your pump. Special Seals and O-rings or a lower pump RPM may be necessary. Booster pump feed is generally recommended. For each degree above 130 F, the inlet pressure should be increased by ? PSI. Special consideration should be given to handling the by-pass liquid. Proper sizing of the holding tank is necessary to accommodate for elevated heat in the by-pass liquid. In systems with the by-pass routed back to the pump inlet, the installation of a Thermal Valve is necessary. Special FLUSHED PUMPS are best in applications from 180-200 F. The flushed pumps feature a specially ported inlet manifold that permits an external flush for lubricating and cooling. Contact CAT PUMPS technical staff for further recommendations. I don't know how hot this pump got in about one minute, but it took me about 3 microseconds to touch it, assess its temp, and fling my hand back. If any of you with a remote temp sensor have an opportunity, do a reading and get back to us. When you consider that the seals are rubber and there are plastic pieces that hold the valve guides together, let your conscience be your guide.
 
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This kind of makes an argument for the dump guns that allow flow through at the gun when the trigger is released.

These are the only type of guns that we have ever used since we started using triggers back in the nineteen seventies.
 
Using a regulating unloader with a non-weep gun will prevent the pump head heat-up problem. A normal bypass regulator just dumps the pumped water right back to the pump, and since the pumping generates heat it's no surprise that the manifold gets hot. I had to disconnect the bay washdown switches when an employee kept leaving them on and I'd walk in several hours after she left to find a pump clattering like a penny in a dryer and making no pressure. One was so bad it even melted the plastic cages of the valves as well as the seal retainers. This was with weep guns in use.
 
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