question thats been bugging me . . .

hey guys .

i have wondered for a while now , and cos Im on here now doing other things Im going to ask now too

on the back of my altenator is some form of device with what appears to be an oil feel line and a drain into the block . . . i have not come across this on the petrol motors i did my time on and it perplexes me . nor is it on the diesel engines around work .

i thought for a second it may be the oil pump but dismissed it cos that's nuts because if you spat a belt you would starve for oil in no time , so that led me to think maybe the oil pump fed this strange thing on my altenator high pressure oil and it drained back . . . Im picturing like the same principle as a turbo . . . so , what is this thing , what purpose does it serve and how does it work ? . i was told on here on my last altenator post that its a vacume pump for the breaks . and if that's the case how does it work and why does it appear to be plumbed into the oil system and not the break booster . . . vacume on petrol motors is sourced from inlet and not lubrication system . . . Im confused ! .

i have been curious for some time i wanna know just what it is and the details on how it works

The unit on the back of the alternator is the vacuum pump for the brake booster (and also various pollution gear) the high pressure oil line feeding it, is there to lubricate the pump and prevent it from seizing, and and the drain line returns the oil to the sump, along with a small amount of air (from creating vacuum)
There should be another hose connected to a banjo bolt on the top. This is the Vacuum line. On my Navara it runs back to the firewall, connects to a solid line that then runs across to the booster

Here is a random diagram i found. Shows the vacuum pump at the bottom. Part 16
http://imageshack.us/photo/my-images/716/001uzg.jpg/

There is not enough vacuum in the intake on a diesel motor because there's no throttle butterfly. Whilst it's on the back of the alternator on the TD, it's built into the block on the QD and the vacuum comes out down low at the front on the driver's side... a much neater system.

Right

after lookin at that diagram and hunting around the bay of that rough and tumble work truck it makes sense

the issue i have discovered tho , and its probably not a problem per sae , but the pipe that actually does run to the booster , runs down , then along the block , under the sump , up behind the battery and along to the booster . . . so with out the extra knowledge you guys provided it looks like its running into the sump . . .

thanks heaps , i get it . . . . its actually really simple now i can see whats goin on , lol ! .

much appreciation Dion and Pinky . . . with it lookin like it was tied into the sump it was driving me bonkers trying to nut it out

Cheers .
Seano .