Having trouble with my Hydrominder 506

[Kirb]

I thought my soap was being diluted so I changed the foot valve. When putting the soap supply line back on the hydrominder I notice when I pull down on the chain it sucks the soap up but when I let go it spits back a little from the tank out of the eductor. I rebuilt the hydrominder and did not solve my problem. I put a brand new 506 in and it still does the same thing. I checked my other 506 on the wax, foam brush, and presoak and they don?t do this. Can any one help?
Thank you in advance,
Kirb

 

[DiamondWash]

Drill a small hole into the tube going into the solution tank.

 

[MEP001]

There definitely needs to be a hole in the drop tube off the eductor to prevent siphoning in case the foot valve fails. It needs to be below the yellow or brown ring inside the hose and above the diluted product.

 

[Kirb]

Thank you for the replies. I will try it this morning.
Thanks again,
Kirb