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## Main Question or Discussion Point

I am trying to determine rod bearing load when a 90 foot pound torque starter motor stalls. I have drawn the geometry in the picture below. I am figuring using a 10 tooth starter gear & a 153 tooth flywheel, so I calculate 15.3 x 90 ft lbs = 1377 ft lbs torque at the flywheel. So if I consider the distance traveled by the flywheel at 12 inches from it's center during a transition from 5 degrees BTC to TDC I get 1.04687 inches. During this same transition, the piston moves .00864. To calculate the effective leverage, I divide 1.04687 by .00864 to get 121.165, then I take 121.165 x 1377 lbs at 12 inches to get 166.844 lbs, and divide it by 2.704 square inches or rod bearing area to get 61,703 PSI on a rod bearing. Where did I go wrong? is the load really that high? A soft metal bearing could not endure that load could it?

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