Does anyone have any suggestions for what to use to prime the pump and hose for a high PSI mix? I run a Olin 540 that likes to plug up every now and then when using a high PSI mix. I have never used any sort of primer. Does anyone have any tips?

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get a sack of lime and mix it up creamy, as i put it into the line i roll it out in a loop so the hose is coated on top and trough out the lenght.

get the pump wet and prime to the reducer into a bucket with a gallon of water, then pour it off into another bucket to separate the rock out then add to your line. sometimes i go 100 ft most times i get 150 and have to clear the tip hose but when it was freezing out i would get 200 ft, using hot water off the truck. that was one of my best days.

some guys just water prime with a little down the hose so they turn the pump up and ram it, all sounds like fun except the no reverse on the ball pump.

i have had some small crushed rock mixes that adding water made slurry.

slick pac tends to not flow past the second hose and thats right where the plug is, if i could get it right i would use it but it has not worked for me. 

I use mortar clay. It's cheap and it works wonders. Depending on how much system I have out I usually put 5-10 gallons of water in the hose first then mix my primer to the consistency of oatmeal, throw it in the hose and you're pumping. My best yet is 850 ft. all the way no plugs!

slic-pac all the way,wet the hose's first.works every time.

Powdered bentonite is great,but add some commercial mortar mix to it! The 3 things you are removing from the concrete slug when priming out are water,sand and cement! Bentonite provides a slurry,but you still need the other two.Making a sloppy slurry and adding some mortar mix works EVERY time! I've primed 600' of 4"pipe and hose with 20 gallons of this kind of slurry and the afore mentioned newspaper wad!