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Nanao MS9-29A Replaced HOT failed again after an hour

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NightWolfx03:
Lemme preface this with the fact that I am still learning how to fix issues on CRTs. I have had a few wins, but I have this unit and 2 Sanwa's that I still haven't gotten working yet.

Anyways I have a Nanao MS9-29A in a Taito Battle Gear 2, It went to a black screen and was making a squealing noise. Pulled the chassis and pulled out the HOT and found that it was shorted. So I ordered some new ones, checked around the board for anything else that stood out (shorts, etc). Put the new HOT in and fixed up the cruddy looking solder joints on string of surface mount resistors under the board near the flyback. It fired right up, the picture looked great, I let it run for a bit and after about an hour I found it with a blank screen and squealing again, so I guess the new HOT failed.

So now I need to figure out what else is out of spec or bad that would have caused the HOT to fail.

I'm open to all suggestions/information, I'm also working on speaking with a friend that is significantly more versed than I am with CRTs when he's not busy.

grantspain:
normal cause is bad solder joints on the horizontal drive transformer, and off course 90% of high power transistors on the market are fakes
also important to test the caps in the power supply circuit

NightWolfx03:
I'll be pulling the board back out soon, I suspect that the HOTs should be original, I got them USA stock and they have a somewhat unique package style. The pictures of the ones from outside US sources have a different looking package. 

I'll check the caps, or for that matter maybe just re-cap some of that area, from what I do know there is a snubber cap there, and usually a few electrolytics in those circuits that can be suspect.

grantspain:
don't forget the horizontal drive coil, i can see it in the photo and the solder joints do not look like they have been reflowed
you can use 2sc4747 as well as the original 2sc4692, make sure its an original and is a TOP3FM package

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