Any electricians out there? Breaker box wiring

[QWIKFIX]

I have a 50 amp GFCI for my hot tub...secondary to my main breaker panel in my garage. After 15 years of use I started tripping the breaker. I did some checking and found that my breaker overheated and actually partially melted at one of the inputs. One wire going into the breaker was a 6 gage wire that was too big for the breaker and the electrican cut down the wires to make it fit...not too many wires strands were left. That wire was also burnt a bit on the insulation. So I bought a new breaker and cut back the burnt wire. I then bought a wire reducer to put on the 6 gage wire then on the other end connected a short section of 8 gage to go to the actual breaker. I used heat shrink wrap to cover the reducer.Now I'm wondering if this breaks any "codes" or if this is kosher. Granted this may not be the actual problem...but i needed a new breaker to start with. Here a shot of it before the shrink wrap. (the bad wire was the orig black wire going to the left input) Thanks for any info

 

[Wes06]

im not entirely sure, but is the 8 gage wire big enough to carry the required current through?

that guy did some shoddy ass work if he just clipped off strands of the wire until it could fit in

 

[Premium08]

Im not sure on codes as i haven't done residential work in a few years, nor have I ever seen a wire reducer like that. i would assume heat shrink is within code. We always used split bolts for bigger wires and wrapped them with a layer of varnished cambric tape, followed by a layer of rubber tape, followed by a final layer of electrical tape.
I know for sure you need to swap out that white wire for a black one or wrap it in black tape. So are the other white wire and red wire done the same way with strands being cut?

 

[QWIKFIX]

Im not sure on codes as i haven't done residential work in a few years, nor have I ever seen a wire reducer like that. i would assume heat shrink is within code. We always used split bolts for bigger wires and wrapped them with a layer of varnished cambric tape, followed by a layer of rubber tape, followed by a final layer of electrical tape.
I know for sure you need to swap out that white wire for a black one or wrap it in black tape. So are the other white wire and red wire done the same way with strands being cut?

Thanks for the info...I will wrap that short section of white wire to make it black. The only wire that had the issue was the black one. I will do some extra wrapping with some electrical tape on the reducer just to make sure its all insulated.