Hi there all!  This may have been answered already somewhere, but I couldn't find it.  Quick question...Is the oil pump for an 01 Vitara located in the oil pan?  Can it be accessed easily to be changed by someone who knows what they are doing without having to drop the motor or tranny?  (clearly not me!)

What engine do you have in the 01 Vitara - it could be a 1.6 or a 2.0 - the 1.6 oil pump is on the front of the engine, the 2.0 oil pump is underneath it.

In either case you need to remove the oil pan, and removing the oil pan is going to be a pain in the butt if you have 4WD - the front differential is in the way - it's probably easier to pull the engine.

Sorry, I guess I should have included that information.  It is a 2.0 liter, 2 WD. 

Well - like I said, on the 2.0 the oil pump is below the engine, you do need to remove the pan - however with 2WD, you might have the clearance you need to drop the pan without pulling the engine.

Question for you though - what makes you think the oil pump needs changing?  They sit in a pan full of oil, are typically well lubricated and rarely give trouble - chances are if the oil pump is worn enough to need replacing, you probably need to replace more than just the pump.

If you are having a problem with low oil pressure the pump should not be your first suspect.

I took it to a garage to have it evaluated so they could tell me what was wrong and they said the oil pump is bad.  It is pumping at about 10# of pressure rather than at about 60# when at an idle.  They said the top half of my engine isnt' getting the proper amount of oil, hence the knocking.  I paid a mechanic to put in a used motor for me last year because mine blew up and there are many things that he did not do correctly.  So, now I am having to have them taken care of.  I thought if it was something that could be done here at home, then that would be cheaper than the $900 the garage wants to do it. 
That is just one of the things that is going on with it.  Or at least the major thing so the mechanic says.  Who knows.  I appreciate your replies though.

The thing about oil pressure is that it can vary depending on a number of factors, rpm, engine temperature and oil weight (or thickness) all play a part - saying the engine has 10 psi at idle and not 60 is only telling you half the story - was the engine hot or cold when the measurement was taken?

The factory specification for oil pressure on the 2.0 engine is 55.5~66.8 psi at 4000 rpm, with the engine at normal operating temperature.

Based on my experience, 10 psi at idle is on the low side if the engine is hot, between 20~25 psi would be normal, but this will vary both the grade of oil used and also the ambient temperature of the day.  The only way you'll see 60 psi at idle is if the engine is cold and has just been started.

Those oil pressure measurements need to be retaken correctly, and I still don't think the pump is the problem - but without being there to see what the pressures are like with the engine cold & warm, at idle and at higher rpm, all I can do is guess.

I would be glad to change you oil pump for half that $900, even 4wd.  So save your money and get oily.  With a used motor, I would check the condition of valve cover to see how often oil was changed.  I bought a parts engine with known knock and the oil pickup was almost all the way gummed up.  (No wonder it had spun a rod bearing.)  Fordem is right pumps usually last a long time, just like motors, when they are taken care of.
Are you sure the knock is in the upper end?

Yes, the knock is on the upper part of the motor.

You might try a can of Seafoam to see if it won't loosten up some
of the junk that might be lurking in the oil system.

About $10 at Autozone, and then get the oil changed after a few hundred
miles with a good quality oil, I like Castrol, always left my engines clean inside
but you can choose whatever you like

Wild

I agree with Wild,

Bought a 4x4 pick-up for a "Job Beater" that had sat for 3 years, (Estate Sale).
No one was interested as it had "Little Knock" in it.
I did what Wild said, and the "Lifter Knock" disappeared. 
It flat towed my Sammy 1681 miles to Nevada AND BACK and is still going.
Also I am a firm believer in Castrol Oils!!
2nd choice is Valvoline.

CAPT

I did the Seafoam stuff and the oil change already to no avail.  One of my friends here recommended that, too.

Well then, the best additional advice I have is to do a real oil pressure
check/test, with a real gauge, cold should be high like 40+ PSI and warmed
up at idle I would not be surprised to see only 10 PSI, but at highway RPM
you should see 40+, a good rule of thumb was 10 PSI of oil pressure for
every 1000 RPM of engine speed, this is not a hard and fast rule, but way
outside that range would indicate a bad oil pump, but more likely a bad/stuck
oil pump blow off valve.

Let us know

Wild