Outer Limits 4x4 Board

I've got 2 rocky A/C's floating around, I will never be bothered enough to hook up AC to mine, so I want to make one into an endless air. Mounting should be a piece of cake cause I have the original bracket for them.

But basically, anyone know the specs on the rocky one? Is it worth using it or if I'm going to the bother of plumbing it up should I use some other (better) pump?

Pull it apart and check it out. IF its VANE - I think you already know the answer....

If its Axial piston then take the opportunity to grease up the friction points and fit a grease nipple as per endless air.

See. I don't know what half of what you just said means, and "pull it apart" scares me

But seeing as I have two not attached to anything I'll pull one apart and post pics up here, unless someone else already knows and can save me the hassle.


Actually. Would a vane pump be anything like the pumps on pressure washers? They have like a circular shaped thing that turns, but its surface is undulating on one side, so as it turns it pushes pistons up/down.....?

A van pump has a rotor with carbide impellers mounted slightly offset from centre in a round cylinder. The impeller blades are not fixed so that they are able to slide in and out of the rotor piece as it rotates. This is neccessary because if you take a fixed point on the rotor, as it turns, the distance between this point and the wall increases and decreases.

Oil is important to lubricate and provide a seal between the impeller blades and the wall.

Does that make sense?

The vacuum pump on the back of the alternator in the diesel rockys uses the same principle, just smaller.

As far as I know the axial piston types have a few pistons arranged in a circle. The cylinders run axially (parallel, along) the pump body. The input shaft directly drives a cam plate (round plate with lobes on one face)which, as it rotates, pushes the pistons back and forth.

If anyone knows different and can set me straight, let me know.

Cheers

Close tabrocky....

The ones used on Applauses and Feroza's dont actually use a rotor - the vanes themselves oscillate in a shaped housing - but you have the operating principle correct. They are very dependent on oil for lube and sealing....

As for axial piston units - your spot on. They are normall oil lubricated but can be converted to grease lube very easily ( some are run "as is" with some oil added every now and then ). They usually have teflon piston rings so don't need oil to seal and don't pump much oil as part of there operation



IF you have an axial piston compressor - then you have struck gold, but would spend the time to grease lube it.

"Endless Air" compressors are simply axial piston aircon compressors converted to grease lube and seem to last very well.