This solenoid box is full of mud, water and roots. I cleaned it out and can see a pinhole leak coming from under the bolt head (not from the gasket). Anyone know how to fix the leak or do I need to replace the solenoid. This is a pain because to cut a long story short I can't turn off the water supply to these solenoids because the owner has a weird temporary watering setup. What type of solenoids are these? Does anyone recognise the brands? Also, there are 4 solenoids but I can only see the need for 3. The 4th one when manually activated doesn't do anything. Could the fourth one be a master valve, how do I tell?IMG_20151027_175721.jpgIMG_20151027_173317.jpg