My 99 with 127K miles has been doing this also; started when the weather got cold. I couldn't get the K&N last time I changed the oil, so used a factory filter. I am due for an oil change, so hopefully I can find the K&N this time. That ATF flush is sounding tempting, since I am not as good as I should be about the 3K oil changes.

 

With the mileage you are getting on your 99, you can't let up on the oil changes. Mobil 1 also makes a great filter.
I would suggest you do a flush and clean up the old engine.

 

I replaced the filter assuggested and added an oil treatment additive that the Land Rover dealer recommended.Thelightstill stays on approximately 30 secondson initial startup.

What should be my next step. I would like to proceed with the lease cost and effort.

1) Change the oil pressure switch? Is there a way to check this before replacing?
2) Check the oil pressure? How do you check it and what are the desired pressure readings?
2) Drop the pan and check the oil pickup tube
3) Replace the oil pump

Thanks for your input.

 

Oil pressure test both when cold and at operating temp, also at idle and at 2000 RPM's.

 

Is it ok to runthe engine with the oil pressure light on for extended periods long enough to perform the pressure tests?
How do I performthe oil pressure check?
Can I use a compressioncheckingguage?
Also, what should the readings be?

 

Yes oilpressures when the motor is hot are a must. This is when my pressure is weakest. For the ultimate peace of mind fit an in cab oilgauge. I don't think the scale will be fine enough for a compression test gauge. Max oil pressure will be 40psi @ ~2500rpm, dropping to ~20psi @ idle. Mine typically runs around 35psi average. Make sure the motor is fully warm (`10mins of run time) for the hot readings. My pressure is highest when the motor is halfway warmed up and doesn't settle down until I've driven a good 5 miles or so in the winter. If you have at least 15psi or so I'd say it was OK for the motor to sit & idle while you're doing the tests. I've seen mine drop to 18psi on a hot day @ idle right after runninghigh RPM.

 

Sounds like you'regoing through what I did last year. I don't think the slight leak will cause you to lose prime. Mine takes few seconds to come on too in the really cold weather. If I left it sitting for a few days and its <30°F I can count toabout 2, maybe 3also before my light goes out. Mine seems better since I cleaned my pick up tube though. I fitted a full time gauge and feel much better now. I kind of gave up worrying about the slow reaction of the oil light in the cold. I'm running thicker oil anyway as I'm in TX (10w40)

 

I just flushed and dropped the pan, with cleaning the pickup tube. Didn't help, but my random tick is gone...

It has been sitting waiting for me to get time, but I did buy a mechanical gauge to check pressure. Did you ever get your tee figured out?

 

Yes I did thanks! It took about two days of running around various places to get fittings that would work and about $60. Even then I had to grind and file parts down to squeak into the space & make it all leak tight. In the end I'm pretty happy with it. I could refine the design some more but that will be a project for some other time. I feel much better being able to check the oil pressure at glance now. I've since found that www.rimmerbros.com offers an oil gauge kit. Next time I'm in the UK I'm going to go check it out. I might see if they'll email me picture of all the parts.

Did you find much crap in the screen of the pick up tube or in the bottom of the pan?