gearbox mounted compressor

[Jacques Reed]

Good Day All,

The attached should answer all questions on where the oil goes in lubricating a transmission driven tyre pump.

Taken from Ford "Special Pattern Vehicles" book. Note passage "A" and wick and non-wick versions and elbow oiler as mentioned by Lang.

The lubrication must be very slow as my pump, missing the oiler, sat for years on a working vehicle in my driveway. Never saw a drop of oil on the driveway under it.

Cheers,

[Lang]

Just at a rough guess I would think the pumps I have, which are mirror images, are for either Ford or Chevrolet application. Both manufacturers probably used the same pump suppliers.

CMP vehicles would not have had exclusive pumps and they would have been a carry-over going back 20 or more years for all sorts of applications. I bet an air pump was offered as an after market accessory for most trucks at the time.

I would think Phil is correct in assuming these particular pumps were not for continuous operation and designed for idle speed tyre filling only. Trucks operating air pumps continuously for air brake systems would certainly have much different gearing.

I have no idea, but I think there may be a physics equation giving the optimum speed of a particular pump design and that is why modern high capacity pumps are screw systems which maintain the flow in a continuous direction rather than pistons.

Lang