When you have an engine with a good differential pressure in the crankcase, the pulse type vacuum pumps work great. Also they draw virtually no HP from the engine since the moving parts are driven via crankcase pulses instead of a mechanical means. Also factor in that magneto type charging systems put out virtually nothing at idle, so the fuel pump running at idle will pull the battery down a good bit at idle. i know my old 140 would put out less than an amp at idle, but push 9 amps or so at 5K. The thinking was if you didn't need a better mousetrap, why re-invent the wheel.
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2011 SUNDANCE B20CCR SKIFF, 2011 YAMAHA 90HP 4 STROKE, 2011 KARAVAN SINGLE AXLE ALUMINUM TRAILER, LOWRANCE ELITE-7 HDI, MINN KOTA RIPTIDE TROLLING MOTOR
2000CC HYDRA-SPORT 225+HP EVINRUDE SOLD 
AND THE PINK JEEP!!!! R.I.P.
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