Originally Posted by mrrblass
do i have to go to a 40 amp fuse for the circuit with two lines running out of it?
No single fuse or breaker should have more than one wire connected to it. It is ok to have one short bit of wire on the fuse and use a wirenut to pig tail this to two lines.
The breaker or fuse size is based on the smallest wire connected to it in that circuit. Do Not increase the size of that fuse. If the wires connected to it are number 14 use a 15 amp fuse. If they are number 12 use a 20 amp fuse.
If this causes the fuse to overload and blow, then you will need to add more circuits to what ever that circuit feeds.
Also you did not say if your garage is attached or detached. It matters here in determining if your grounding is done correctly.