K4600 c625 cap keeps bulging

curtislv426

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When I got it the screen had full max brightness and the C625 capacitor with bulging. I gave it a full cap kit and the monitor looked great for a couple hours and then it got brighter and brighter and brighter as that c625 capacitor started bulging again. And I replaced the capacitor again and it bulged a third time. I replaced the neck board and that didn't help and then I replaced the flyback and that also did not help. Has anyone else experienced this or has an idea of what might be wrong with the chassis? Thanks.
 

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it probably means it's exceeding the voltage rating or something shorted.

I never needed to analyze K4600 schematics so I don't know if there's anything inline there that could be shorted and causing this.
 
it probably means it's exceeding the voltage rating or something shorted.

I never needed to analyze K4600 schematics so I don't know if there's anything inline there that could be shorted and causing this.
Yeah, I agree. Bulging is overload - it's gassing. So either a bad lot of caps, or you have a short pulling too much current in the circuit.
 
Yeah, I agree. Bulging is overload - it's gassing. So either a bad lot of caps, or you have a short pulling too much current in the circuit.
had a 6100 exploding caps in the HV cage years ago. it got sent off to get fixed, the wires were basically empty insulation. so if this monitor was extracted from a swamp somewhere... lol
 
had a 6100 exploding caps in the HV cage years ago. it got sent off to get fixed, the wires were basically empty insulation. so if this monitor was extracted from a swamp somewhere... lol
You never know.

Generally, when a wire is used as a fuse, the magic smoke comes out really fast.

Years ago (late 1970s) I was riding in a parade in a friend's antique fire truck go cart. It had a Harley Davidson transmission, and had a siren on the front. My friend ran a wire to a battery that he dropped into the back of it.

He ran it across the engine.

Yep, you guessed it. He pushed the button, the insulation had burned through on the hot exhaust, and ALL the insulation burned off the wire in around a second.

That was it for the siren.
 
You never know.

Generally, when a wire is used as a fuse, the magic smoke comes out really fast.
ive heard .22 rounds work well 😀, I cant remember what happened that myth busters episode.

Some craziness ive seen is shady operators taking the blown fuse and then just wrapping solder around one end, strand it to the other end and wrap it around that end and put it back in lmao. Seen it on a Cyclone redemption game, and I think a pinball before.
 
which board had the board marked backwards for a cap on top and correctly on the underside?
 
I believe I found the problem. R634 is completely open and has the battle scars to prove it. It's supposed to be a 2.2 ohm resistor and is in line with the bulging cap. I'll fire it up tomorrow night and report back
 

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New r634 fixed the problem. Ran it for 11 hours straight with no problems. Thanks to those who chimed in.
i just saw this and i had the same problem many years ago but i have been out since i had surgery last week and still have another five weeks of restricted duty but that was the same resistor i found too.
 
i just saw this and i had the same problem many years ago but i have been out since i had surgery last week and still have another five weeks of restricted duty but that was the same resistor i found too.
I hope you are recovering well, Peter. I didn't know you went under the knife
 
I hope you are recovering well, Peter. I didn't know you went under the knife
yeah its been a rough month with a navicular fracture of my foot playing hockey, then two weeks later MRI and more work on it, the colonoscopy the following week then 5 days later hernia surgery. i have had about enough of this shit.
 
yeah its been a rough month with a navicular fracture of my foot playing hockey, then two weeks later MRI and more work on it, the colonoscopy the following week then 5 days later hernia surgery. i have had about enough of this shit.
I'm sorry man. I hope this annoying chapter in your life is over soon.
 
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