They were very smooth runners. In good condition, they are as dependable as any other motor. They have the advantage of no water pump, thus no impeller to wear out. The pressure suction cooling system was well proven by the time 1930 rolled around. Have never owned an A65, but have owned both A50’s and A70’s. There might have been some slight differences in things like exhaust cut-outs, carbs, and so forth, but I don’t immediately recall anything that was a HUGE difference.
One thing I have found with these is that the internal crankshaft bearing gets worn, and when that happens, they are very hard to start & run. Also, if compression is at all below 60 PSI you need to re-ring it to bring it back up above that level. Below 60 PSI they will start out of water, but not in it.
Hope this helps.
best,
PM T2
He's livin' in his own private Idaho..... I hope to go out quietly in my sleep, like my grand-dad did..... and not screaming, like the passengers in his car...
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