Looking for SA-8500II Advice

They aren't exactly open, but they're in megOHMS kind of jump around a lot? Maybe the caps doing weird stuff. I checked the good side to and it was similar. Is that as good as open?
 
looks fine ..
check power supply voltages .. its a dual supply so right side might be bad
check at power supply board
 
Okay... I know I'm asking a lot.... But I think the supply voltage should be 24.5v and I could check at pin 63. Does that make sense? Or am I looking for AC voltage coming from the transformer?
 
Pete thanks for your help tonight.... At least ruled some stuff out right? I'm going to try to get back into it tomorrow. Let me know if you have any visions or anything. Thanks again!
 
How's the STV diode, the one that has a horseshoe shape and twin leads coming out from it at the top of the amp board? Be VERY careful in checking the leads as replacements are next to unobtanium. That has an effect on the bias as things heat up to keep voltages in check. If it's bad you could get the heating you're observing as the outputs are running too hot. The differential pair (single 5 legged transistor) could also be bad, but doesn't sound like it since you don't have wonky offset readings.

Does the amp heat up when the pre and amp are isolated (jumpers pulled)? If not, you could do comparison voltage readings between the good board (L) and bad board (R) to see where the problem might lie.

My SA-8500II restoration. Might provide some useful photos, etc to help you fix yours.
 
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Yes, but be extremely careful with the leads. They are very brittle. This diode screws down onto the heatsink and adjusts as temp increases.
 
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