WG25k7191 No Picture

Deadpool66

New member
Joined
May 21, 2009
Messages
1,839
Reaction score
13
Location
Minnesota
I have a k7000 monitor with no picture. The chassis looks clean, Looking for suggestions on where to start.
 
Check the fuse, HOT, and VR, fix all the bad solder, replace the caps, check the flyback for cracks, etc...
 
Well I have a cap kit and the fuse is good.... Noticed the flyback is cracked around the focus knob would this cause the monitor not to fire up? Ive gone ahead and ordered a flyback kit from Bob Roberts should have ordered another cap kit for the working monitor doh!
 
Last edited:
flyback failure is common on these, particularly if the flyback's adjustment knobs are white. if you find cracks, don't turn it on anymore -- everything in the circuit path gets destroyed lol

just wait until you get the new flyback in.
 
I haven't attempted to turn it on since the first test. The knobs are white on the flyback btw I'm hoping for an easy fix.
 
I haven't attempted to turn it on since the first test. The knobs are white on the flyback btw I'm hoping for an easy fix.
Is this from your 6 player X-Men? I think the flyback nobs on mine were originally black, but I replaced them anyway. I was just wondering in terms of when WG might have stopped using those white knob flybacks.
 
Yes its from the X-men 6player both monitors are k7000, However only one has the white knobs.
 
flyback

i have to say this is the best monitor that wells has ever put out. In my experience the flyback rarely went out and i fixed 1000's of these. Of course these are getting older and they are going to fail eventually. White knobs/black knobs? never had any real problem with either flybacks.
If you need one i have one that i have been testing for a few days.
 
i have to say this is the best monitor that wells has ever put out. In my experience the flyback rarely went out and i fixed 1000's of these. Of course these are getting older and they are going to fail eventually. White knobs/black knobs? never had any real problem with either flybacks.
If you need one i have one that i have been testing for a few days.

see, that's what Randy Fromm's flowchart said too, that the flybacks rarely go bad. but that flowchart's probably from the early-mid 90s too... I witnessed a flyback failure firsthand on one of my K7000s and the results weren't very pretty. I had to replace traces on it, and now probably as a result, I have 3 faint black lines on the left side of the picture cause they ran to a side of the C36 cap. almost certain that's what did it.

it looks beautiful otherwise though, it's 20 years old now. back when Zenith made tubes that were worth a shit.
 
I don't replace the flybacks on them unless they are showing cracks or improper function. or if the customer requests it...
 
I don't replace the flybacks on them unless they are showing cracks or improper function. or if the customer requests it...

yeah, mine showed no hints of it, no focus or brightness fluctuations. just normal operation one day, nuked the next (and even more ironically, it happened while I was doing my first flyback replacement on a K7500). even when I replaced it, there were no noticeable signs of cracking or leaking. what else would charbroil the traces of the side of the flyback circuit going to C36?
 
what else would charbroil the traces of the side of the flyback circuit going to C36?

Heat. Whoever made those chassis for WG used the cheapest possible way to adhere the traces to the wafer. They are notorious for having pads lifting or separating during normal cap kits...
 
if you didn't see my thread, my chassis clearly had a hole in it, maybe about the size of a dime, or bigger. it was hilarious. grabbed some diode wires and started hacking and it worked.

the WORST chassis I've ever worked on was a 33K8000. every. single. pad. on the flyback. lifted. off. it's amazing I even hacked that thing back together.
 
The Randy Fromm chart still has good info - but the info on the flybacks "rarely" failing is out of date. These days the failure rate is pretty high.

In my experience, if you have a K7000 with a white knobbed fly, replace it.
 
Alright guys got the new caps and flyback installed plus a new hot. Now I need to know what tools are needed to add the pin connector to the wire on the fly that connects to the neck board. Im also wondering if i should replace the voltage regulator the bob roberts kit didnt include one but i keep reading about it in other repair posts.
 
Now I need to know what tools are needed to add the pin connector to the wire on the fly that connects to the neck board.
I cut the old one off, soldered it onto the new fly, and sealed it with heatshrink tubing.

Im also wondering if i should replace the voltage regulator the bob roberts kit didnt include one but i keep reading about it in other repair posts.

I did, better safe than sorry on a 20+ year old device.
 
at least check the vr and did you check c36?

I honestly truly hav enever ever seen a properly working, NON cracked white knob flyback.

Lik ei said i dont know if its age or build quality or what but every frickin one i have ever seen has at least had a hairline crack in it, sometimes lots and theyll zap you when you go to grab the adjustment knobs heh
 
Any harm in firing it up without replacing the voltage regulator? I have it all reassembled and would like to see if it will live once again but would hate to ruin the effort I put into it thus far. I'm a complete noob when its comes to electrical work Ive got soldering down and the whole continuity thing but I don't know how to test caps, regulators, ect. I do have a nice auto ranging meter so tips are welcome.

I also don't really want to wait for the part to come in the mail as it wouldn't arrive till next week and at this point and I'm tired of looking at all of my games torn apart with pieces all over the floor gotta get this shit put together so I can enjoy them ;-) Plus Im tired of tripping over monitors and sheets of glass in my gameroom.
 
If the VR is bad, it will blow the fuse, so go ahead and fire it up.

I'm gonna bet it won't work, due to some solder issue. If it doesn't, measure the B+...
 
If the VR is bad, it will blow the fuse, so go ahead and fire it up.

I'm gonna bet it won't work, due to some solder issue. If it doesn't, measure the B+...

Cool that wasn't a shot at my soldering skill was it ;-)
 
Back
Top Bottom