[dandg30]

I need the easiest yet still safe and legal way to hook up my hot tub. I have a 200 amp main service in the house which feeds a detached garage, which has its own small panel out there. I am wanting to use an existing 50 amp breaker(previously used for a welder) which has a 3 wire heavy gauge black run of wire that dead ends into a 3 prong receptacle plug.I want to remove receptacle and install the plastic spa pack junction box with the 50amp gfci in its place. My tub has about 10 feet of flex which will connect into there nicely.TUB IS 4 WIRE/EXISTING PLUG WAS ONLY 3. Do I need to run a new 6-8 awg wire all the way from panel ? And if so where does it come from in there? The 3 wire has a blk with red stripe, a solid blk, and an uncoated wire which is connected to a ground or neutral bar in panel. The 2 coated wires go to each main lug there.Can I make this work with only perhaps a jumper wire in my gfci box?It has 2 bars in there, but will I also need to run a ground stake to the gfci box? Only place I am aware of that is staked is the main house panel.
Correct me if I am wrong but its my understanding that the 4th wire I need to add is considered a neutral wire , which when added to the 2 hot wires and the ground already in my 3 wire set up, will give me proper combo of wires to safely hook up my tub. If you need pics I surely can take some but I think I have explained fairly accurately and asked what I needed to ask, hopefully it can be conveyed back either in a diagram form or nice thorough explanation. If all else fails I will call an electrician, just trying to diy and gain a little more knowledge in the area of electricity and how it works. Thanks in advance to any and all who can help out.
Dan
PS: I hooked it up earlier as I thought it would be hooked to just the 3 wires and as expected I'm only getting power to my blower and ozone generator. The pumps and jets have yet to function.I assume that's because of the 4th wire which would supply those items with power which I didn't know where to hook it. Hence my reasoning that perhaps a jumper wire in the gfci box will power that simply... let me know asap . Thanks

[tkrussell]

I need to suggest you do hire an electrician. I am not convinced the garage panel can handle a constant load to heat a hot tub, along with the blower and other hot tub loads.

The wiring serving the tub needs to be #6 copper, 4 wire, with two hots, one neutral, and one equipment ground, ALL INSULATED.

NO GROUND ROD is needed. The one you see at the main service is the only location for grounding.

The garage panel must have the neutral and ground separated. The neutral bar must ne insualted and isolated.

Since this is a hot tub, not a good DIY project to start with .