I've got the rebuilt '56 235 into my '50 3100. The sheet metal is off so I can get to everything easily. I had to drill & tap the end of the crank to install a retaining bolt on the balancer. The balancer was slightly loose when I reassembled the engine. As discussed in prior threads, I had to install a modified fan spacer on the stock fan then "tweak" the fan very carefully to get clearance between the fan and radiator in the front and the balancer bolt at the rear. My question is what is the minimum safe clearance between the radiator & fan and the fan and the balancer bolt? I've test run the engine only to break it in and had no problems but am not sure how much the stock 235 fan flexes under a load and RPM when driven. Thanks.

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