@Steve.
for your pain, you got a good practical idea of what "hydraulicing" was.
Plus you could tell if an engine was rich or lean by the sound of the exhaust. Even more so on glo-plug engines.
Even worked on R2800 with open exhausts (DC-6), but NOT on Convair 440 because siamesed exhausts were fed into augmentor tubes which muffled everything. I was always much better at starting the DC-6 than the CV-440!