Plugged drain - frost free hydrant

[PJH]

Anybody have any tricks to unstop a plugged weep hole in a frost free yard hydrant? Other than digging it up, that is. . . I have four hydrants out of seven that are plugged and won't drain. All of them are bedded in open graded gravel. I've dug up one, and it won't even drain with nothing around it. It seems to be corrosion - we have lots of minerals in our well water. I actually don't mind digging, but there's a hundred other things that are also calling for attention.

Paul
 

[wilamayb]

I dont have any thoughts on repair without digging it up but some folks install the hydrant with a short exension on the drain with a tiny street L on the end, pointed down. This may or may not help. If it is hard water plugging it up I think this may just be a regular occurence for you.
 

[Greenday]

With the hydrant in the off position plumb up a fitting to screw onto the hydrant with a schrader valve so you can put air pressure into it and see if it will clear the drain back
 

[Dusty MI]

[showcrop]

Water doesn't drain quickly through gravel like it does through sand or stone, so some of the water draining out can get higher than the drain then carry fines with it to the drain point. The correct procedure is to use some stone under and around the drain to enable the water to drain quickly down and away.
 

[Justin SE IOWA]

I agree 100% with Greenday
 

[PJH]

I tried 125 PSI yesterday on three of them. No luck. Gonna take one apart tomorrow. I'm wondering if the rubber/leather shutoff can deform and block the drain hole.

Thanks,
Paul