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Spiderman Pinball was missing +5VDC

Today I revisited the Stern Spiderman pinball that was not booting. When turning on the machine I would have a garbled display and only GI lights were on. The game would not attempt to start if you hit the start button. Metering the Cpu board at J11 I found that I was only getting 3.6VDC at the 5 volt line. I then measured the Power/Driver PCB at J16 and found that I was not getting the 5VDC there either. I had read that the heatsink on the LM338K on the Power/Driver board can cause this low voltage or no voltage. The black paint on the heatsink can cause the screws holding the LM338K to not make good ground contact. I sanded the black paint off of the heatsink, on both sides, where the screws make contact. I reinstalled the heatsink and then the board back into the machine and now have 5.02VDC. I played several games to check for stability and everything seems to be working well. In the near future I will go through this machine and clean, wax, rebuild flippers and make any other adjustments it may need. Pictures attached show the display before repair, heatsink before repair and after. And finally the game fully working. 

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