sprinkler valve leaks

deck hand

First I had a continuous running sprinkler ( rain bird ) last month
I replaced the top half of that zone's valve (exact ) same kind eight screw model rainbird 100. $ 35.00
I'm having trouble setting the screws down all the way because of some sand in the screw hole, I washed it out and used air pressure to blow out the holes, but it still dribbles,
Now another valve head leaks a bit too?
Is there a way to run a drill throught the bottom opening the bottom to clear the sand out of the holes, enough not to ruin the threads?
To change the whole valves would require me to dig up the whole valve systems and pipes. 4 per box,

deck hand

Kap

How about trying a battery powered dust vac to get the sand out?

You could put a straw or tubing in the vac opening and duct tape around it to close off the rest of the opening to create more suction through the tubing.

I install all my valves with unions for ease of repair/replace/maintenance.

downunder

Not familiar with this specific head but any chance you could use a thread tap to clean them out and/or maybe run the threads just a little deeper?

swade

Deckhand, I got your pm, couldnt reply by pm since I dont have enough posts. I left this response in your profiles visitor message area.

Hope it helps

I dont have nearly enough posts to send a pm. Im not familiar with that model valve, it doesnt show up on the rain bird website. If the valve is leaking between the bonnett or the body it is one of the following things. 1 The diaphram isnt sealing properly either by defect or as your re-installing the bonnett it is moving off the diaphragm. 2 there is a hairline crack in the top or bottom of the valve. 3 you are missing the small O ring that seals the solenoid to the port on the body of the valve, ( i have lost many in the hole while taking the vavle apart.

If it were me I would buy a complete new vavle and try replacing the easy parts one at a time. What you have left you can save for future repairs. If parting it out doesnt work, replace the vavle itself.

**After reading your post I havent ever tried to drill out the hole, you most likely will hit a thread and damage it, I have used pipe cleaners, we used to keep our trucks stocked with a few and they help.

Keep in mind you should never overtighten a valve, the weakest part of the bonnet is at the thread holes. If the valve still leaks with all the screws "hand tight" then my guess is the bonnet has a small crack in it.

Another thing, when you tighten the screws are you going in a star pattern like when you change a tire?? if not you may not be sealing the top evenly and hence the leak.

Let me know how it turns out