How you guys are primed out, if it is necessary to pump indoors, and there is no possibility for А-pattern of boom?

My english is too bad?

If I have system hooked up, I get a  yard of grout. If no system, Tight Z or A Frame. I use water. Goes right through.

prime out into the back of the mixer, you have to know about how many strokes it takes. mine takes about 7 so when I am on stroke 6 I tell the driver to put the drum into full charge. then you have enough mud in the hopper for a couple strokes to get to the good mud. after you have mud out the end of the tip hose kink it off and swing over to your system . dump your slurry/ primer into you hose, hook up and pump it in slow. it is the same as priming a line pump once you get the boom and first hose primed into the truck. have done it this way for a long time with few problems. the best way is to get a 1/2 yard or so of gout and prime the whole system at one time... where I pump the contractors rarely make that possible so I use this method.

we never use h2o,either slikpak ,drilling stabilizer fluid,or 9 sack grout, we use the grout only in situations where we have 80 ft or more off the end of the boom or 150' or more off our linepump,we mostly use a product we get from one of our customers that do drill shafts called novagel it works great and a bucket lasts about 1-2 years on a pump and if you charge a prime charge the profit margin is way up there