How clean does the inside of the boom pipe have to be? Shinny clean or does a few rocks and a little bit of grey slurry going to hurt. I wash sucking back a sponge.

alot of ppl suck back with just one sponge an it leaves a little grout in the pipe but i always suck 2 back with a bucket of water in between them pipe looks brand new everytime

The cream inside the pipe will normally stay wet for a couple days, if you have a good ball and suck it back real slow, you shouldn't have a problem. But the two balls and water between works like a charm.

Good subject, I use one sponge (wet) and have never had trouble. I primarily run a 2002 36Z Putz and have to raise the boom so that sections are at least running down hill to suck the sponge back, this is not the case with the 2001 46X that I fill in on, what makes the roll and fold different from the Z, any insight?

p.s 36m usually takes 8 strokes in reverse to get the ball back, 46m takes anywhere from 13-18 depending on the slump of the concrete (obviously the lower the slump the more it takes to get the ball back)

Well I generally water wash.But when I do suck a ball back,I will take off the tip hose and lay the fourth section almost flat behind the pump.Squirt in a bunch of water.run my RPM's pretty low,set the volume on about 30%.start suckin my ball back and stand the 47 up,Make about 8 strokes and start bringing her back down.I look for all the water to come back into the hopper and then listen to the end of the pipe,She makes a very distinctive sound when the ball gets into the swing 90..Pipes are generally spic and span after that But as for the little bit of slurry your talkin about as long as we are not lookin at like half an inch in the deck pipe and every 90 good and coated your good.Like stated earlier it will stay wet in the pipes for a while and generally scrubs out an the next job..Only to be replaced at the end of the job

Lately I have been sucking back with the boom in the cradle (thanks to the advice of a fellow cp.com member), great way to suck back through a Z boom. I believe this method cleans better as the sponge comes back at a slow consistent rate, rather than being pulled slowly up one section and then rocketing downhill through the next. I use two round sponges roped together with a couple gallons of water in between.

But if your getting rocks left behind that tells me that you are suckin your sponge back to fast and its pulling over the top of some mud,,,start changing your swivel gaskets and turn your pump speed down when bringing the sponge back,Also..Are you recirculating to get the concrete good and wet'ish before you pull your sponge??

I suck back with a damp 8X8 square sponge slow is the key it takes me about 1min. to suck back I do this the same with our 32m roll and fold and our 38m Z fold as long as its in the A frame it sucks back gr8 no residual cream on the pipe never had a problem in 7 yrs. I've never heard of sucking back with it in the cradle don't really see the need and I would not trust that water wash stuff suckin back a sponge is allot easier in my opinion but different STROKES for different fokes no pun intended.

As clean as you can possibly get it ! Clean pipe is golden. Works everytime. Kinda clean works most of the time. but it's bit me in the ass before. Last job on Saturday evening always think of how much you want to have a nice start on Monday morning!

suck up a little water out of my bucket.then a sponge.i never set the boom down without sucking back a sponge

I still raise the 3rd and 4th in the air if I can to let gravity help out. I do the 2 spon ge method with a little water in between. It cleans them very well and suck back slow so you dont colapse the sponge and suck threw it instead of against it. I would bag my sponge as well. That way your sucking against a solid object and not threw it. Also if your bag doesnt come back on the sponge you know your pipes have buildup in them and it would be a good time to check them.