Rear 4WS Pump - other uses??

[bazeng]

Hi Guys,

I was just wondering, is the rar 4ws pump a constant pump?
Does it constantly move liquid around?
How does it work exactly?

I was thinking, would it be possible to mount a rear oil cooler and weld some fittings on the rear diff cover, then plumb the 4ws pump to the diff fittings and the oil cooler to circulate the diff oil. I was even considering increasing the capacity of the rear diff by welding the rear cover with some sort of sump.

Is it possible?

Considering oil temps are one of the main reasons that the parts fatigue and die. This may help with longevity.

Opinions?

 

[Dialcaliper]

Sounds like a pretty good idea - It's driven off the diff ring, and it seems to be fairly linear with vehicle speed. I'm sure if you went with a slightly lighter gear oil and ran it through a cooler, the pump shouldn't have a problem.

Here's the flow diagram out of the 3000GT Tech Info Manual

The only problem you might run into is that it's a high volume, high pressure vane pump, just like the power steering pump. The Flow peaks at 6 lit/min (360 lph), at 90 miles per hour, and at that speed it's already hitting 150psi. (it scales at about 50psi for every 30mph). The pressure keeps rising linearly, and the internal relief valve doesn't open until 570psi, so you'd need to plumb in a relief valve back into the diff, or you might end up bursting your oil cooler at high speed. Either way, its going to be moving a lot of fluid.

 

[bazeng]

I wonder if the pump would also work as a water pump (water to air intercooler)..

Thanks for the info mate, your always very helpful.

 

[curtis]

^that would work and at those pressures would remove a huge about of heat. Only thing I can think of that might be a problem is the size of the lines and volumes but with a low volume system like this it may pass the fluid slow enough to remove more heat than a large volume system. Imagine your heater core in your car. Cars that don't really get warm in the winter all benefit from a restrictor placed in the line this would work in the same manner. I had a nissan 240 once that I froze in until I machined out a piece of aluminum at work, nothing special just a cylinder shaped 3/8 chunk of aluminum with a 1/4 inch hole in the middle and placed it in the return line from the core. All 87-93 mustangs have these in the heater core hoses from the factory.

Straight water couldn't be used but a mixture of red line water wetter and antifreeze for lubrication and maybe alcohol in the mix. You would have to break open a thermodynamics text book to see exactly the correct size for the heat exchanger and the IC core but you may be on to something with this. Meziere makes 20 to 55 gph pumps but since there for engines the pressures are only 9 to 16 psi. I guess, can't seem to find a line pressure figure on them.

Now kind of out of context but years ago a company built an air intake for the ford mustangs that went from the mass air meter to the T-body. Inside the tube it had an aluminum tube coiled around the inside super tight and two fittings on the outside. It was designed to place in-line in the ac system and they claimed something like 30 hp. But at Full throttle and the speed of the air moving I really don't believe the tubes really cooled that much but may have rotated the air enough to straighten the flow and thats where the added hp came from......