A good indicator with an airseeder of having to replace boot springs is when it is folded. When pretty bad, the back part of the boot where the seed flap is connected is hanging making a noticeable gap, where the better ones will be barely off the disc if at all. For box drills or the middle row of a seeder you should here it snap shut against the boot and should be a bit hard to be able to wedge your fingers between the disc and boot to pull it away. Bad springs you can grab the boot easily from the boots rounded top and pull it away.
I'd say to rebuild a full opener arm which includes all joints and a shaft that is not seized where you can hammer it out with wood buffering the hammer, takes from 2 to 3 hours, which is considered a minor rebuild where only seals are replaced. If you have to pull it to press out the shaft then it could be 5 hours especially if you have to go as far as cut out the shaft and replace it and the spindle. Or if you have neglected it so bad the hub also needs attention then add another hour. So, best case 1.5 hours to worst 5 hours. And that is one skilled mechanic at the same speed as two half experienced ones or four drunk farm hands.
A good indicator with an airseeder of having to replace boot springs is when it is folded. When pretty bad, the back part of the boot where the seed flap is connected is hanging making a noticeable gap, where the better ones will be barely off the disc if at all. For box drills or the middle row of a seeder you should here it snap shut against the boot and should be a bit hard to be able to wedge your fingers between the disc and boot to pull it away. Bad springs you can grab the boot easily from the boots rounded top and pull it away.
I'd say to rebuild a full opener arm which includes all joints and a shaft that is not seized where you can hammer it out with wood buffering the hammer, takes from 2 to 3 hours, which is considered a minor rebuild where only seals are replaced. If you have to pull it to press out the shaft then it could be 5 hours especially if you have to go as far as cut out the shaft and replace it and the spindle. Or if you have neglected it so bad the hub also needs attention then add another hour. So, best case 1.5 hours to worst 5 hours. And that is one skilled mechanic at the same speed as two half experienced ones or four drunk farm hands.