My First Month of Land Rover Ownership: Oil Leaks and Mission Creep

I discovered my Discovery's oil leak! Well, one of them, anyway.

Joy of joys, after a thorough cleaning at the DIY carwash and a few minutes laying on my back with a flashlight and a rag, I found the source of my Land Rover Discovery’s oil leak! Though, bummer of bummers, slight complications soon followed.

When I last updated you, dear reader, I was stoked on blasting off something like thirty pounds of caked-on mud from underneath this 1997 Disco I picked up for a few grand. I really went to town with the wand at my local DIY carwash; woe betides the filtration system that had to deal with it all after I left.

At first I was a tad lost; I found the leak but didn’t know what to call its source.

I could tell it was a sensor, but, couldn’t quite pick which one. One of the first things I’d in my research was a camshaft position sensor O-ring, so initially I ordered that for something like $1.95. Though upon closer inspection of a very hard-to-read diagram, and asking around on Facebook groups, it actually turned out to be the oil pressure switch. Eh, whatever, it’s all cheap. The sensor’s O-ring cost a whopping $0.95, and the company I ordered it from has a warehouse not terribly far from me in Simi Valley, California. The cam position sensor’s O-ring will probably give up the ghost at some point anyway, so I figured I might as well have it on hand.

While I was in there, meaning while I was on RoverParts.com ordering the proper O-ring, I figured why not also order a new switch for $9, a new oil pan gasket, a front main seal, and two oil change kits. All of these parts netted me something like $70 all-day shipped, so… why not? All of this seemed pretty cheap all things considered, and I’ll be well-prepared for future oil changes and leaks.

And yet, my $2 order had already ballooned pretty dramatically. Oh well.

My First Month of Land Rover Ownership: Oil Leaks and Mission Creep
You sneaky little bastard. – Image: Peter Nelson

After some minor annoyances, I replaced the oil pressure switch and its accompanying O-ring, and sure, enough no more leak!

By “minor annoyances” I mean that it was really tight quarters for wrench-turning. I had to remove the oil filter and use an open-end wrench to loosen the switch something like three millimeters at a time, and doing the reverse of removal in the same tight quarters. Also, the new sensor required a 22mm wrench, whereas the old one required a different size that I didn’t have, so I had to run down the street to AutoZone. But I got it! After driving it around and inspecting a tad closer, the area around the block below the switch is dry as a bone.

However, I still saw some spots on the cardboard below my parked, up-to-temp Disco. I crawled underneath to inspect and saw that there was some very light seepage from the oil filter and the front main seal. Good thing I’ve got a front main seal on deck. The source of my oil filter might not be the filter itself, so I’ll have to continue my research.

Sigh, all the jokes about Land Rovers leaking oil are, well, no joke.

Meanwhile, there’s about half a can of Seafoam coursing its way through the crankcase at the moment (for non-car people, it’s not actual ocean water—Seafoam is a detergent additive that’s popular for dumping into fuel tanks and crankcases). I plan to change the oil sometime in the next week or two to drain it out and replace it with thick, quality, conventional 20W-50. Apparently these engines run best on the thick stuff, and hopefully this’ll also help stave off future leaks. Though, hot oil is still pretty darn viscous when it encounters presumably-old-as-hell gaskets, so we’ll see.

I’ve still got other stuff to tackle, too! I have to to re-instate the disconnected power steering system, inspect for leaks, and replace stuff as necessary. And track down a light ticking at idle, low in the RPMs. I’m stoked on being able to tinker on stuff after years of flawless reliability with my Mazda2. Though, I’m crossing my fingers that this’ll all go well and I can finally enjoy some quality off-road rascality soon.

Peter Nelson

Peter NelsonPeter Nelson has been wrenching on and playing with cars since he started driving them quickly between the cones at Chicagoland autocross events in his late teens. Nowadays, he can be found wringing out his Mazda2 at tracks all over California. His writing background includes Winding Road, Donut Media, and Autolist.com. He's also an avid cyclist and '80s/'90s action film connoisseur. Contact the author here.