I just found a 6 inch cap with a female water hose connection attached .This no doubt will clamp up on the back end of the pump.I fortunatly have never had to use this particular cap.I am curious to see how many people have used this system,and how well it works.If I had to use it I would probably put two sponge balls in the 6 inch elbow clamp this bugger up and hope for someone with good water pressure.Anyone had an experience with this?Curious to see how much water pressure it will take to clean a boom,and if the water will go around the sponges and cause problems.Hopefully by opening the back end alot of the mud will gravity feed out of the back end,and also most of the mud will freefall out of the hose end.Probably the only time this would be used is after a catastrophic engine failure..

Oh heck yes,one time.That was all it took.A stieble box shaft failed to pumps.throw ball in,mixer hooked up and off to the races.The tip was to high off the ground for blow out cap.Saved the boom,stayed home one day,shrimp on the barbi and a nice headache.

This is very interesting! Could you post a Pic? Sounds like a 2nd great emergency device!  

my blow out cap has an hosebib w\ a ball valve and a 1/4" air quick cupler /w ball valve, when in dout hook water and air , this little bugger will get even that simi hard  mud out of the boom  it saved my boom more than once

  Thank you for the quick response.Anyone ever have to "steal" air from a mixer,if so ,what was your method?

Hi,well kinda sorta.Over the years several times,a driver would say I only have 20 gal.Far out,when the water is gone his air pressure kicks in.Saved my bacon on many of occassions.

all of our pumps have quick couples and enouff hose to go the to the end of the boom, when you put water in the boom pipe it takes less air to do the job

if you have simi hard mud in the boom i like to blow from the tip in witch u need a 5 in cap or unless u got 4.5 boom pipe,incert the the ball, fill boom pipe with water and shut the ball valve and turn the air on fillpipe, if u run out of air dont panic  disconect air and water and stand boom up  and pump back if it comes back do a second wash waterwash and your safe, if it doint comeafter u stand the boom u got biger fish to fry  boom party

 Many,you are probably a good one to have close in dire situations.............

thanks bisley,I learned many old indian tricks over the years.I did however graduate in the top 10 at the school of hard knocks.Never got the scholarship.

Vasa the Viking,

I did not write a word!

It is like the dunnage deal. Everyone knows, so I will not keep bringing it up ;~)

The best deal was when the mixer had 30 or 40 gal left when you hook up the hose.

Good wrecker drivers make excellent pump operators... they think, then do.