I have a 1996 Discovery SE7. It has north of 186 thousand miles on it. Here are my cards:

I drove the vehicle to a friend's house and everything was fine. I visited with friends for a few hours and upon leaving, went to start the vehicle. The oil light was on and the tick was loud immediately upon starting. I shut the engine off, waited for a moment and tried again. Same problem.

After checking oil levels (they were fine) I pretty immediately determined that it was obviously an oil circulation issue, and my first thought was a bad pump. Further research ruled that as unlikely (though still possible).

I have found through research that beginning in 1996 until 1999 the Discovery V8i engines had improvements that prevented the oil pump issues that had been prevalent before and apparently after though they still have a sludge problem.

I had recently changed oil, but I have since discovered that I probably used too light a weight. I used 10W-30 and I have learned that 15W-40 is probably better. I also used the FRAM tough-guard filter from Autozone.

My current candidate problems are:

1) Fouled Pickup
2) Fouled Filter
and finally 3) Fouled Oil Cooler

I am going to diagnose the filter first this evening by swapping it out with a new one, just to see if that solves the problem.

If that doesn't make a difference, I will pull the oil pan, and inspect the pickup and then visually inspect the oil pump while the engine front cover is still attached. I am hoping that pulling that for inspection isn't necessary, but I am certain that I will not be so lucky.

I would like, to anyone who is willing, some input, thoughts, or ideas on this.

Many thanks in advance!

 

Did you do an oil pressure test? That is the only way to know if the oil pump is good or not. Just because your Disco isn't one slated to have one of the bad oil pumps, doesn't mean it will last forever.

 

Agreed! I am not ruling it out per se, I just find it difficult to believe that the oil pump would have died upon turning it off. An oil pressure test is next on my agenda if, for example a new filter does not solve the problem.

I figure that a pressure check would be an indicator of any of the above-mentioned problems.

 

It very well may have been on it's last legs and the 10-30 did it in finally. What brand oil do you normally use? Do you commute to town, or strictly in-city driving?

 

Also check for clogged oil cooler. It is in series with pickup so suction.. oil pump unlikely to stop like a light switch. See tech area for write up on jumbo low loss oil filter.

 

I think before you run it up again farting around that you remove the pan. You'll see what you need to without screwing your crank further. If you continue to run it you'll see what my other thoughts are.

Not the filter or cooler, c'mon. Yes the oil is thin weight but not so much to reduce pressure to less than 8lbs no matter what crappy condition your motors in.

It's either the pump grenaded, screen or bunged bypass spring. Good luck. Once you fix it then put the gauge on and play around. Loose your crank, go buy another truck, it's cheaper.

 

What this guy said.
The oil pump has a bypass, so if there is a obstruction somewhere the oil will circulate to the engine, clogged filter, oil still circulates to the engine, just unfilterd,the engine does not want to self destruct anymore than you want it to.
Drop the oil pan, clean the pick up screen, put it back together, noise and oil light are now off, if not its the oil pump.
The middle of the line Fram and top of the line Fram filters are good filters, the cheap ones are crap BUT have nothing to do with oil PSI.

 

UPDATE:

I removed to oil sump, and pickup. When I removed the pickup, a gush of oil came out around the mounting point. I was not able to find what was obstructing it but I cleaned it with mineral spirits anyway. I also cleaned out the sump its self.

Upon reassembling it, after the lubrication system established pressure, the oil indicator light went off and the noise was no longer present.

The oil cooler hoses leak terribly, but then, they have for a while.

Thanks to everyone who responded. You were helpful.

 

Take a peek at this flow plan from the RAVE. Looks like oil is sucked up thru pickup into cooler, so when you took off pickup gravity would have drained back what was in cooler. How gunked up was the pickup itself? Any pix of the gory details?

I've always wondered if we could reverse flush the pickup screen by using a garden sprayer and pumping it (solvent of choice) in from the oil cooler port, and out with oil drain and change.

 

@Savannah Buzz

The pickup had a significant amount of buildup on the screen and there was thermal plaque round the linkage and within the pipe itself. There was also a significant amount of loose material in the sump.

I do have pictures but they aren't that clear, and no closeups of the pickup. I thought of flushing the system backwards from the cooler-to-engine line, but I would want to do that with a compressor with mineral spirits and I didn't have the equipment.

When I am not as critical on my need for an operational vehicle, I wanted to take it apart again, flush the oil cooler, and then do what you are suggesting after using oven cleaner or similar chemical to really take off the scored on oil residue on the pickup and the sump. I would also need to re-thread the pan bolt channels in the block as some of the ones I encountered last night had been cross threaded.

As a whole, my experience working on this engine was fairly strait forward and not entirely unpleasant.