Transformer heat to hot?

[dvbme]

So the rocket i built sounds great but gets to 62c after a couple of hours or faster depending on the volume i use it at. I'm assuming that the NOS Mallory, CDE caps i bought off ebay 40uf-450v and 20uf 450v might be to blame. can i test this or might something else be wrong?. i used the BOM and layout 3-9-9.

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[sluckey]

A good filter cap will be room/ambient temperature. A cap that is passing current will be warm of hot.

[Stevem]

What's getting up to 145 degrees, the PT or the filter caps?

How close are the 4 output tubes to the PT?

[maxkracht]

What is the environment like? Does the cabinet have adequate air circulation? Is the room itself hot? I am very weary of old electrolytics, regardless of being NOS, but they usually give you hints when things are going bad.

[2tone]

These power trannies run hot.. AC 30, Matchless DC30, Trainwreck Rocket etc. A decent transformer can stand 190 degrees F fine.. Old AC 30's had the wax melt from the power trannies often..Still ran fine..

[Stevem]

Just keep a eye ( meter ) on the PTs secondary voltages, as there will come a temp where due to heat related added resistance that the voltages will start to sink and the heat will just keep climbing.

Then it’s fan and ventilation time or a PT with more mass and higher current output.

If you find your heater voltage gets below 6.1 then your already in Shark infested waters!

[dvbme]

I'm using it through a v4 cab 8ohms one creamback 75 amongst the eminence 50's with a drummer on the third hour it gets the outside of the power tranny hts-9144 62c i put a fan on it and it keeps it to 50-55c. so last night i took it out of it's shell and played through a single 16ohm 75w for an hour got up to mid 40's C caps were room temp. the tranny is 4 inches from tubes.

[dvbme]

A good filter cap will be room/ambient temperature. A cap that is passing current will be warm of hot.

While probing the 20uf cap on the left i heard crackle, chopsticked the cath and lo and behold looseness. more soldering, now no crackle. i just need to get a practice for three hours and test the heat. Thanks for the guidance.

[TUBEDUDE]

Used electrolytics are as risky and desirable as used condoms.
Not the place to go cheap. New is always better in this case. Metalized film is better but new electrolytics
are the minimum acceptable.

[Reeltarded]

Used electrolytics are as risky and desirable as used condoms.

11 years later and you just can't let it go. I was joking.

I put together a JTM50 about ten years ago and could not complete startup without increasing the HT fuse by .25A. The PT was ANGRY hot. I rebuilt the power string where I had found no fault and the temp dropped to warm. Never figured out where the current draw was. I think I remember reading about batches of bad cap cans from mid 2000s and decided that was likely my problem. I can't remember which brand I stopped using. I'm old.

And I never tried to buy or trade used condoms. It's a damned lie.

[TUBEDUDE]

I did buy a NOS sports car, that was about as wise.