About 4 months ago a kid in high school sold me his blown kicker zx550.2 for $50. He was in a bind and I thought that maybe it was a decent amp because of the kickers made in the 90's were really nice. I got it apart and it had a lot of damage. I thought I had screwed myself big time but I have it working now. I changed all 10 IRFZ44Ns with IR brand fets ( probably better than the cheap Chinese originals lol ) I also changed all 10 100 Ohm resistors and the main IC (TL494CN). It also had one blown Tip35 in one of the channels. I pulled the Tip 35 and it powered on and played. Checked the Resistors on the channel as well as the other transistors and everything was fine so it appeared. I replaced the Tip35 and reassembled the amp. But this is where I think I screwed up.. I had some thermal grease and thought maybe it wouldn't hurt to apply a thin layer to the transistors and heat sink. Well it sure didn't help so I'm assuming maybe it did not need the grease?? The amp gets hot when played at high volume. It doesn't get hot when its on but not playing or even playing at low volume. It gets warm which I would expect. I powered it on with a 10 amp fuse in the B+ and it didn't pop my fuse. I played it at a decent level on home speakers at full range with the 10 amp fuse still inline. Sounded clear and didn't show any signs of other possible problems. I let my cousin hook it up in his suv on a pair of brand new L7 15s running in parallel @4 ohms mono. Gain was up less than half it could be set. He played it as loud as he could for 2 days ( at least 6-8 hours). He said the amp was getting hot but never shut off and never distorted. Said it was fine.. He did have a bad ground running to it, it was at least 3ft long 8 gauge wire. I know that was not good. Power wire was kicker brand 4 gauge. I guess what I'm getting at is.. I want to sell the amp but I see how people install their stereos around my city and they do the unspeakable.. I don't want to sell it and have someone come back saying I ripped them off but at the same time I spent a lot of time fixing it and I'm probably going to ask $100-$125 for it. (I have the box, birth certificate and base knob also) I live south of Houston and its high 90's everyday lately so is it to be expected the amp would get hot? Thanks for the input.
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