WG K7000 keeps blowing 3 Amp fuse in Ultimate Mortal Kombat 3 Base

toploaderleo

Member
Joined
Jul 21, 2014
Messages
106
Reaction score
0
Location
New Jersey
WG K7000 keeps blowing 3 Amp fuse in Ultimate Mortal Kombat 3 Base

Hello, I'm working on an Ultimate Mortal Kombat 3 machine for a friend. I replaced the 25" Wells Gardner K7000 chassis inside with one I bought off-line that someone had rebuilt, a mouse had nested in the original one & instead of rebuilding that one & cleaning off the droppings & urine I opted to go with buying one someone had already got up & running.
So I get the rebuilt chassis, pop it in & it works fine. I move on to work on some of his other cabinet & let it run for about an hour before adjusting anything. I start adjusting the contrast, brightness, horizontal everything with no problems. The picture was still a bit darker than I would've liked & the text was a bit blurred so I decided to adjust the focus & brightness on the flyback. I adjust the brightness & get a better result, it's still a bit blurry though. So I try adjusting the focus & as soon as I do the whole cabinet shuts off. The 3 Amp fuse at the base of the cabinet had blown, so I replaced it & there's a buzzing sound & after a couple of seconds the fuse blows again. I tried to make sure I didn't short anything on the chassis or check for any sign of something blowing on the chassis & nothing. When I disconnect the power to the monitor the cabinet works just fine.
Is it possible the flyback just went? The flyback was definitely replaced before I bought this chassis & the chassis worked just fine prior to trying to adjust the focus. I was using a metal screwdriver when adjusting it so there's a chance something arced or shorted but I don't know. I know when the flyback goes on a K7000 it blows the fuse on the chassis but the fuse on the chassis is just fine it's just the 3 AMP fuse int he MK3 base that goes & it's definitely related to the monitor some how I'm just not 100% how & wanted to check with everyone before replacing the flyback.
 
the focus is an extremely high voltage component of the flyback. with so many crappy reproduction flybacks out there it's entirely plausible that it was just a dud. if you look at the caps on the chassis, are they blue Richey caps? if so, the parts probably came from Bob Roberts, and he circulated a lot of bad K7000 flybacks for a long time.

did the flyback make any kind of hissing sounds when you adjusted the focus? that's a major tell that it's no good.

I've never heard of this happening before, but like I said, a lot of duds out there. I would buy from security0001 or Buffett.
 
I had the exact same same issue with my SF II with a 25" K7000 after installing new cap kit and flyback. It still wasn't right so I kept mucking with it and had to move the whole cabinet at one point, which is when the 3 Amp fuse started blowing. Went through a 4 pack of them and was at the end of my rope. I finally realized that the ground wire that goes to the marquee light fixture had been squished by the edge of the metal monitor frame and it must have been severed completely when I moved the cabinet. Once I repaired the severed ground wire the cabinet fired right back up and no more fuses have met their end.

Not certain that this is the cause, but might be worth checking the wires to the marquee light to make sure they're not damaged. Good luck!
 
The flyback did not make any kind of hissing noise & didn't appear to have any sort of cracks or leakage. I do have a spare K7000 flyback I can pop in there to try out, wont do any harm in trying. I'll also inspect for shorts once again.
 
Back
Top Bottom