I have 2 A-70s. One to run and a pretty one to hang on the wall to get oohs-and aahs. a little bit of Mothers Metal Polish cleans them up really nice.
Bullet proof magneto, not so fun to start when the temp approaches freezing (fuel doesn’t want to atomize).
I have Ks and Js of the same era and I notice in my (cold) lake they carbon up in the exhaust outlet on the bottom of the powerhead — it effectively prevents scavenging of exhaust gases. Maybe that’s a place to inspect before you spend hours of pulling to produce a few pops.
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