It works! Thanks again g1!
The tricky part for me was missing the fact that the replacement part I purchased for Q9 had a metal backing, where as the original did not. See attached photo.
Any book recommendations for Electronics Repair / Troubleshooting?
Thank you again everyone! I look forward learning more here

So far so good with the dummy load.
Variac at 120VAC
Sinewave at input
Very clean sinewave at output
Drawing 0.5 Amps at 50% Volume

I think I'm ready to try with the speaker next.

Thank you! Things are looking much better!

Replaced Q4, insulated Q9.
Shorted input
No Load
Variac at full AC voltage 120VAC
1.03VDC across R97
0.29VDC at output

Is there anything else I should check before testing again with the 8ohm load?

The heatsink is a large aluminum fin style with Q7, Q8, and Q9 attached. When I received the amplifier for repair it had what looked like white lithium grease between the transistors and the heatsink and no mica insulators. I cleaned and replaced the grease with Arctic MX-6 Thermal Compound when I replaced the transistors. Could that be the problem? Does Q9 need to be isolated?
Small update: The version of the Q9 D600K that I used has a metal backplate that is connected to pin-2 the Collector (the original did not have an exposed backplate). I'm going to make an insulating wafer and will update soon.

ah!, you are correct, I swapped R97 and R98 while typing.
Q9 has fresh thermal paste and seems to be tight to the heatsink.

R97 is 100 ohms
When voltage across R98 is 5VDC then R97 is 0VDC and the voltage across R41 is 7.4VDC

Thanks g1 and saturated. When the VARIAC is at about 28-30VAC there is 5VDC across R97, and -1VDC at the output. Current draw is still negligible.

I am measuring current as well, so far it stays very low. I'll try upping the AC voltage today. I'm just worried about R97 burning up, or Q4 shorting again. What do you think I should look for next?
Also, what I am experiencing is almost identical to this post: https://www.ssguitar.com/index.php?topic=4235.msg42173#msg42173
Thanks again for the help

Greetings, I am having an almost identical problem with a Hartke A35 here:
https://www.ssguitar.com/index.php?topic=5343.0
Thanks for any help with this

     - Jesse

At this point I have tested and/or replaced most components in the output section. With the input shorted, I am seeing about -1v DC at the output when the VARIAC is at about 45VAC.Any thoughts on where to look next for issues?

Schematic for Hartke A35

Greetings, I have been attempting to repair a Hartke A35 amplifier.
I am using a Variac, and an 8ohm Dummy Load during testing.
When I received the amp, Q8 and R51 were clearly damaged. I have replaced Q7, Q8, Q9, R50, R51, D13 & D14.
After replacing these parts I slowly powered it up again, this time causing Q4 to fail (a short from Emitter to Collector), and R97 is starting to burn up.
I then replaced Q2, Q3, Q4, Q5, Q6, as well as C23, C61, & C64, (R42 measures ok).
Something is still drawing too much current through R97 and causing it to overheat. (R98 seems ok)
With R97 lifted I have + 33 & - 33 volts on the V+ & V-
Does anyone have any ideas of what else to check, or what could be wrong?
Thank you for any assistance!

     -Jesse