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Russell Ashley · 08-13-2018, 10:16 PM

I'll make one more comment on this topic and then I'm done. Only posting this because I don't think most people know that you could tow start a hydramatic equipped vehicle.
Found this using Google:
"The Hydramatic was fitted with two pumps to pressurize its hydraulic control system and provide lubrication of internal components. The front pump was a variable displacement vane unit driven from the fluid coupling housing, which meant oil pressure would be available immediately upon starting the engine. A relatively constant pressure was maintained by moving a slide inside the pump, which had the effect of changing the pump's displacement and therefore the volume of oil being delivered.

The rear pump was an unregulated gear pump driven from the transmission output shaft, which meant it was capable of pressurizing the transmission if the vehicle was in motion. This feature made it possible to push-start a vehicle with a dead battery if the vehicle could be accelerated to at least 15–20 mph (24–32 km/h). At higher speeds, the rear pump provided all the oil volume that was needed to operate the transmission and the front pump's slide was nearly centered, causing that pump to produce little output."

08-13-2018, 10:16 PM	#13
Russell Ashley Registered User Join Date: May 2010 Location: Lawrenceville, Ga Posts: 2,640	Re: Towing a 1954 Chev 1/2 ton truck I'll make one more comment on this topic and then I'm done. Only posting this because I don't think most people know that you could tow start a hydramatic equipped vehicle. Found this using Google: "The Hydramatic was fitted with two pumps to pressurize its hydraulic control system and provide lubrication of internal components. The front pump was a variable displacement vane unit driven from the fluid coupling housing, which meant oil pressure would be available immediately upon starting the engine. A relatively constant pressure was maintained by moving a slide inside the pump, which had the effect of changing the pump's displacement and therefore the volume of oil being delivered. The rear pump was an unregulated gear pump driven from the transmission output shaft, which meant it was capable of pressurizing the transmission if the vehicle was in motion. This feature made it possible to push-start a vehicle with a dead battery if the vehicle could be accelerated to at least 15–20 mph (24–32 km/h). At higher speeds, the rear pump provided all the oil volume that was needed to operate the transmission and the front pump's slide was nearly centered, causing that pump to produce little output."