F.E. Myers Air Blast Orchard Sprayer Information

[r8f1k]

My FMC sprayer had a 3 cylinder piston pump. Just watch your pressure guage as you’re tank gets low, when it starts to flutter shut the pump off . Running it dry after spraying a load for a few seconds shouldn’t hurt, just don’t drive all the way back to refill with it running.
The centrifugal pumps used in some sprayers are the type you’ve really got to be careful not to run dry.

I think the longest it has been run with little to no water was probably 1 minute while it initially primed.

In the searching I am doing, I have found that 2.25" piston cups are very common. My cylinder liners are 2". Is it possible that there should be 2.25" piston cups installed in this unit, giving a 1/8" on each side of "squish"? The piston cups that are currently in the unit are EXACTLY 2", but were they originally 2" or are they worn down to the cylinder sleeve?

 

[Seven Gables]

I think the longest it has been run with little to no water was probably 1 minute while it initially primed.

In the searching I am doing, I have found that 2.25" piston cups are very common. My cylinder liners are 2". Is it possible that there should be 2.25" piston cups installed in this unit, giving a 1/8" on each side of "squish"? The piston cups that are currently in the unit are EXACTLY 2", but were they originally 2" or are they worn down to the cylinder sleeve?

I’d think if ordered them for your model pump and supplier knew the cylinder diameter they’d of sent the correct ones.
Been 30 plus years since I put a set of cups in my old FMC but I do remember when new they were a little larger than the bore of cylinders. That’s why I softened them in boiling water, still had to drive them in with the special tool and hammer.
Are you having trouble getting and holding pressure? When you put the new ones in we’re they real snug fit like I described?
I’m 99% sure you haven’t ruined them from just running them until It primed.

 

[Seven Gables]

Been so long I can’t remember for sure but I think I always greased the cups before installing also

 

[r8f1k]

I’d think if ordered them for your model pump and supplier knew the cylinder diameter they’d of sent the correct ones.
Been 30 plus years since I put a set of cups in my old FMC but I do remember when new they were a little larger than the bore of cylinders. That’s why I softened them in boiling water, still had to drive them in with the special tool and hammer.
Are you having trouble getting and holding pressure? When you put the new ones in we’re they real snug fit like I described?
I’m 99% sure you haven’t ruined them from just running them until It primed.

The new units are exactly 2". They are in there snug, but not super tight. My concern is that they leak a little BEHIND the cylinder head and onto the ground. Water is getting around the piston cups in some way or another. Hence my question on putting in units a little larger than the cylinder bore. They definitely did not need to be heated up or pounded in place. I was able to get them sized by a guy who serviced hydraulic equipment and these units just happened to be 'laying around'.....no real stock of a variety. Dumb luck really.

 

[Seven Gables]

Just by your description of how they went in I’d have to say the cups are little too small, kinda tough call though. Going by memory I’d describe putting the new ones in my FMC as very tight, definitely had to whack that pipe tool with a small 2-3lb sledgehammer pretty good.
I’d call a reputable Myers pump supplier and tell them what your situation is , they should be able to tell you exactly what size the cups should be for your model.

 

[r8f1k]

Just curious, were you guys able to see the video of the control panel?

 

[Seven Gables]

Yeah I could

 

[old and tired]

no problem seeing video. Why did you put blue at the top, when sequentially it should have been after the orange? or do the lights indicate where on the fan the nozzles are set at?

 

[r8f1k]

no problem seeing video. Why did you put blue at the top, when sequentially it should have been after the orange? or do the lights indicate where on the fan the nozzles are set at?

So each light represents a nozzle and the least used nozzles are going to be the upper most (blue) nozzles. Very few of my trees have any canopy at that high of a degree above the sprayer, so I made it the last selection of the panel.

 

[r8f1k]

As I have explored the internet for more piston cups, I have found that there are many available in China. I am not keen on buying Communist made good, but they also offer matching cylinder sleeves to go with the piston cups. My thought would be to get an outside dimension of my cylinder sleeves and then try to order some replacement sleeves and cups. It seems that 2.25" is a very common size, so not too much larger than my unit. I could pull the head off this coming fall and take it to a machine shop if I can't pull the sleeves out myself or resize them. I do have a good lathe, a mill and a press, but I don't think that I could mill the inside of the head to oversize it for a different cylinder. I don't really want to turn down cylinder sleeves either to make them thinner, so I would probably have to outsource that labor. Pressing in new sleeves shouldn't be too bad, keeping the depth correct is about the only thing that seems to really matter. My long term thought would be to get this up and running with a slightly upgraded pump and then have an inventory of piston cups to keep it running.