1996 Land Rover Discovery XD Eco-Challenge build

preacherman

Explorer
Coolant Leak

Over the next few weeks I discovered I was unquestionably loosing coolant somewhere. I spent time after every drive looking under the truck for signs of a leak. Checking all the likely culprits (hose connections, the throttle body heater etc…) to no avail, I started to get frustrated. Since the entire cooling system had been replaced, I knew there was only a few places it could be, none of which I liked to think about…The confusing thing was that the truck was not overheating, only loosing coolant. My constant coolant checking and measuring probably helped, as I never let the truck run a bit low on coolant.

I decided to park the truck and do a full run up. Enough was enough; it was time to figure out what was going on once and for all. First I ran a compression check following the RAVE procedure. Engine cold, WOT, I was so surprised by the result I ran it twice, just to make sure I didn’t screw something up. Compression was a very consistent 165-172psi in all cylinders! The truck only has 81,000 original miles, but I was still pleased the engine was in such great shape. The spark plugs also looked good with no signs of “steam cleaning” that would come from a leaking head gasket between cylinders.

Next I ran a pressure test and pressured up the cooling system. I did this several times in several conditions. I did it with engine cold, engine hot, after setting hot, after setting cold and at warm up. I really wanted to make sure I got a good test under all conditions. I used a small camera bore scope and stuck it anywhere I could get it in, around, and beside the engine. It told me quite a bit. (the camera I was using did not have the ability to take screen shots or I would have grabbed a few)

I found a leaking freeze plug and that both head gaskets where starting to ever so slightly weep at the front of the engine on both sides. The freeze plug was behind the motor mount and was 90% of the leaking, but there was a “weep” between the head and engine on both sides in the front. I talked with a few other mechanics that all suggested I just replace the freeze plug and “see what happens with the head gasket” but I just couldn’t let it go. Since this truck is going to be driven in the backcountry I decided I could not let it go. I also had some oil leaks from the upper end I wanted to address so I called up Atlantic British and ordered a full upper end kit with all new head gaskets, seals, gaskets and head bolts. When everything came in, I called a buddy and we took a Saturday tearing everything down.

Getting started (check out how nasty that intake is!)
 

preacherman

Explorer
Head gasket rebuild Eco-Challenge Discovery

Tearing everything down I found what I have come to expect, a few surprises both good and bad. Overall I was pleasantly surprised by the internal condition and shape of the engine. Originally I had thought I would do the teardown and rebuild in a single day, but after I got everything open and apart, I decided to slow down and address a few small issues while I was in there.

First, I discovered a layer of sludge oil in the heads and valve covers. While it was not enough to be a problem, it was enough for me to take everything up to work and use the industrial parts washer to clear it out. After everything was cleaned out well, I took my time inspecting everything for wear, cracks, and damage. The heads, rockers, rocker arms, springs, pushrods, lifters and hardware all looked great. We have a machine shop at work, so I threw the heads on our leveling slab and had our machinist mike them with a dial caliper. The first head was only .005 off, but .002 was factory spec. I took the heads up to an engine machine shop and had them give them the once over to make sure I didn’t miss anything. In the end, they didn’t find anything either and they shaved off .008 on both heads to get everything squared up and back perfectly flat.

Checking Heads for warp


After getting shaved


While the heads were off and everything was exposed I made sure to closely inspect the pistons, cylinders, sleeves and block. The head gasket was starting to thin and narrow where I saw the weep, but there was no full breaks or compromises. I was glad I changed it, but I was hoping for a bit more of a sign it was bad. In the end, I really think it was at the very early stages of going out, which is a good time to catch it, before any damage was done. I honestly think if I did not have the leaking freeze plug, I would not have noticed the Head gasket for several thousand miles. I think it worked out well that I found it early. The gasket looked fine everywhere else and it was obvious no coolant was leaking into the engine or combustion chambers.

Inspecting Engine before cleaning it up



The visual inspection of the cylinders confirmed what the compression test told me, the engine was in great shape. After closely inspecting the pistons, block, sleeves, and cylinders, I have no worries about the shape of this engine. It was worth the peace of mind to crack it open just for that.

After seeing how much gunk was in the intake I decided to clean it as well as I had the heads. Taking the intake completely apart, I put the elbow grease and industrial parts washer to good use. I also ordered a complete set of matched, rebuilt fuel injectors. The end result was amazing. The intake looks like new and the new matched injectors smoothed out the idle and got me some power back.

Clean intake!



I had an oil pan gasket left over from my first parts order so I dropped the oil pan and cleaned it out as well. While the oil pan was down, I cleaned out the pickup screen and checked the bottom end of the engine. It was as problem free as the top end. I also discovered that a major oil leak I had was from the oil pan and the crankshaft position sensor. I cleaned and resealed both of those. While I had the pan off I checked the rear main seal and was glad to discover it was bone dry.

Oil pan before cleaning


The last problem I addressed while I had the heads and intake off was an issue I had been experiencing with an O2 sensor. I had replaced both front O2s sensors, but my ultra gauge kept getting a reading that the O2 temp sensor was out of temp range during the preheating warm up cycle. I had run enough tests and chased enough ghosts to feel like it was a wiring harness problem. The issue was that the harness was on the back of the engine by the transmission and almost impossible to reach. Now that the top end was off I was able to peal back the wiring loom, inspect the wires, clean everything up and made better connections. The extra job paid off, as the problem went away after everything was cleaned up. I also cleaned up some wiring from when I had replaced the engine temp sensor a few weeks before.

The last thing I did was replaced the leaking freeze plug with a new one from Atlantic British. The ease that the bad one popped out was a little disconcerting but after inspecting all the others, I feel confidant the problem is solved.

My buddy came back the next weekend and we took our time buttoning everything up, following the RAVE the whole way. After getting everything back together the Land Rover purred like a kitten.

Before (check out the sludge and dirty intake)


After (no sludge, and look at that intake)


So how do you test a truck you just rebuilt? You take a road trip of course!
 

pdXDisco

Observer
This is both intimidating, and inspiring. I probably should do the same, but frankly have never done anything so involving with an engine... thanks for the great write up!
 

preacherman

Explorer
Road trip test

Heading out the next weekend we took a road trip down to Leaky, Tx for a weekend on the Frio river. At only 4 hours away it would be a great short road trip to test out the rover. Since we were traveling with other friends, it would also provide some backup if we had any trouble. On the way down the temp stayed 195 deg the whole time and got 11mpg.

The abandoned town hall of Stiles, Tx.



Land Rover by paul talley, on Flickr

The Frio river low water crossing.
Land Rover by paul talley, on Flickr
Land Rover by paul talley, on Flickr

On the way back, the Rover started running a little hot. At 205 deg I wasn't worried but it was only 75 deg outside and I thought it would be running cooler. 10 miles from home it spiked and jumped to 212 deg. It never got above 212, but the ambient temp was only 75, it should not be running 212.

I was stumped, I had replaced almost everything in the heating system. The radiator, coolant tank, all hoses, thermostat, fan clutch, radiator cap, even the hose clamps. The only thing I had not replaced personally was the heater core and the water pump. I was told that the water pump had recently been replaced and it looked new. I had also pressure checked the heater core while replacing everything and it flowed well and held great pressure.

The crazy part was that over the next few days I could get the system to run hot (between 210 and 215) but when it ran hot changed. SOmetimes it was at idle, sometimes it was at highway speeds. I started thinking I was crazy. I spent hours under, around and in the engine bay with a laser thermometer trying to figure out if I was actually running hot or if I was getting false readings. I tested the thermostat and it was stuck closed. That must be my problem. I replaced the new Land rover brand thermostat with a “failsafe” brand 185 deg thermostat and thought my problem was fixed. A quick test drive proved I still had a problem…. I was at a loss.

Finally, I decided I would put a new water pump on and just see if the newer pump was bad. I ordered up a water pump and dug in. When I got the water pump off, I felt the bearing and it felt fine. Turning the water pump over, I heard something rattling inside. Upon close inspection, something was jammed in the impellers of the pump. Pulling it out with needle nose plyers I discovered this.

Untitled by paul talley, on Flickr

Untitled by paul talley, on Flickr

It was some type of rubber gromet. It looks like someone must have dropped it in the open cooling system while working on the rover. Since I had a new water pump in my hand I went ahead and replaced the water pump. The rover now runs at 185 deg in almost every condition.

I was now ready for the ultimate road test. A week long 4x4 trip through Colorado with my family.
 

preacherman

Explorer
Lights!

Now that the Rover was running well I could finally move on to the fun stuff. We set a date to go out to Colorado to spend a week around Ouray wheeling the high passes and Alpine loop. With the mechanicals done, I focused my attention on items like the lights, CB, ham radio, on board air, high lift mount and shovel mount. Basically the items I would need for the trip.

I started with the lighting. The roof rack had all of the original lights but they were not wired up. I first checked the individual lights themselves by taking a small 12v battery and making sure they all worked. Next, I planned out my wiring. I wanted to run the hard to find factory aux light switches but had trouble finding the switch themselves. I needed three switches (one for the 2 spot lights, one for the 2 flood lights and one for the rear back up light) but could only find the bezel holder and not the switches. I knew it would be a tall order to find the switch as they dried up years ago, but I was determined to try. After searching for weeks, I had to throw in the towel and get some aftermarket gauges.

The next problem I had was I wanted to keep the originality of the Eco Challenge and not modify the dash in any way. I spent hours trying to find a suitable place to mount the light switches, ham radio and CB radio. Eventually, I found that I could mount the lights in the location of the factory dash pocket. The light switches are fit in using modeling foam and can be easily removed but gently prying out the switches if desired.

Dash switches
Land Rover by paul talley, on Flickr
Land Rover by paul talley, on Flickr

Once I got the light switches worked out I started wiring the lights themselves. I wanted to use relays for each pair of lights as well as with them to be key on so that if accidentally bumped when the car was off, they would not turn on and drain the battery. I bought a few spools of 100ft wire and got to work.

Roof rack wiring
Land Rover by paul talley, on Flickr
Land Rover by paul talley, on Flickr

I had the same problem with wiring the relays and running the wires as I did with the dash. I wanted to make sure that I cut no new holes or changed anything about the truck at all. It took a long time to figure out how to run everything but I finally made it work. For the relays, I ran one relay for each lighting pair. I made a bracket that used existing bolt holes in the firewall to mount the relays. I had 4 relays even though I only needed three. I went ahead and mounted all four relays, that way if I blow a relay, an extra is already mounted and can be switched over by simply unplugging one and plugging in the other.

Untitled by paul talley, on Flickr

After almost 200 ft of wiring and 65+ connections, I had working lights!

Front
Untitled by paul talley, on Flickr

Rear
Untitled by paul talley, on Flickr
 

El Matador

New member
Now that the Rover was running well I could finally move on to the fun stuff. We set a date to go out to Colorado to spend a week around Ouray wheeling the high passes and Alpine loop. With the mechanicals done, I focused my attention on items like the lights, CB, ham radio, on board air, high lift mount and shovel mount. Basically the items I would need for the trip.

I started with the lighting. The roof rack had all of the original lights but they were not wired up. I first checked the individual lights themselves by taking a small 12v battery and making sure they all worked. Next, I planned out my wiring. I wanted to run the hard to find factory aux light switches but had trouble finding the switch themselves. I needed three switches (one for the 2 spot lights, one for the 2 flood lights and one for the rear back up light) but could only find the bezel holder and not the switches. I knew it would be a tall order to find the switch as they dried up years ago, but I was determined to try. After searching for weeks, I had to throw in the towel and get some aftermarket gauges.

The next problem I had was I wanted to keep the originality of the Eco Challenge and not modify the dash in any way. I spent hours trying to find a suitable place to mount the light switches, ham radio and CB radio. Eventually, I found that I could mount the lights in the location of the factory dash pocket. The light switches are fit in using modeling foam and can be easily removed but gently prying out the switches if desired.

Dash switches
Land Rover by paul talley, on Flickr
Land Rover by paul talley, on Flickr

Once I got the light switches worked out I started wiring the lights themselves. I wanted to use relays for each pair of lights as well as with them to be key on so that if accidentally bumped when the car was off, they would not turn on and drain the battery. I bought a few spools of 100ft wire and got to work.

Roof rack wiring
Land Rover by paul talley, on Flickr
Land Rover by paul talley, on Flickr

I had the same problem with wiring the relays and running the wires as I did with the dash. I wanted to make sure that I cut no new holes or changed anything about the truck at all. It took a long time to figure out how to run everything but I finally made it work. For the relays, I ran one relay for each lighting pair. I made a bracket that used existing bolt holes in the firewall to mount the relays. I had 4 relays even though I only needed three. I went ahead and mounted all four relays, that way if I blow a relay, an extra is already mounted and can be switched over by simply unplugging one and plugging in the other.

Untitled by paul talley, on Flickr

After almost 200 ft of wiring and 65+ connections, I had working lights!

Front
Untitled by paul talley, on Flickr

Rear
Untitled by paul talley, on Flickr

Great freakin job brother!


Sent from my iPhone using Tapatalk
 

preacherman

Explorer
Ham and CB radio

Next, I turned my attention to the ham radio and CB radio. I again wanted to mount them so that they could be removed without any sign of the installation. It took me a while to figure out how to run all the wires, antenna and radio without cutting any holes or drilling into anything.

Land Rover by paul talley, on Flickr

I really don't like CB’s especially since I have my ham license, but since I would be traveling solo and in an area that many people off road in, I thought it might be a good idea in case I needed anything or had any problems. I mounted the antenna via a mag mount Wilson, then placed the radio between the passenger seat and center console. The radio has a front mounted speaker so it worked great.

CB
Land Rover by paul talley, on Flickr

The ham radio was a bit harder. The dual band radio I have is a Yaesu ft7900r so it has a remote mount radio face. This allows many different mounting possibilities. I mounted the body of the radio under the passenger seat and the head control via a remote face head mount. I then put an external speaker under the driver's side seat.

Ham mount

Land Rover by paul talley, on Flickr

Everything at night
Untitled by paul talley, on Flickr

I wired the radio alongside the aux fuse block I mounted for the lights.
Land Rover by paul talley, on Flickr

Next, I mounted my shovel and co2 to the roof rack.

Untitled by paul talley, on Flickr

Like before, I mounted everything in a way that it could easily be removed with a trace if I ever want to change anything.
 

preacherman

Explorer
Land Rover Discovery Eco-challenge on the Alpine loop

With everything ready, we packed up and headed out to Colorado for a week of wheeling. Since we were traveling by ourselves, I was somewhat worried about how the Land Rover would do. As we headed out I knew that we would either have a blast or regret taking a 20 year old vehicle on a 2,000 mile road trip.

One aspect I was also concerned about was that I would be pulling a full loaded off road trailer. Even though I have pulled this trailer all over the southwest, until this point I had only pulled the trailer around the block with the Discovery. Hookin up the trailer we headed off to Ouray, CO and into the unknown. .

Driving through New Mexico
Untitled by paul talley, on Flickr

It turns out my fears were for nothing. The Eco-Challenge did fantastic! My first tank of gas netted 9.7mpg fully loaded with the trailer running between 65 and 70 mph through west Texas. I was very pleased. While the small tank did mean we had to stop every 200 miles of so, we settled in and had a blast. Finally we arrived in Colorado and started up the passes.

Highway 550 outside Silverton
Land Rover by paul talley, on Flickr

The next week we wheeled, hiked, rock climbed and lived out of the Land Rover. It was by far the best truck I have ever had off road. We did the alpine loop, including 4 passes over 12,500ft. The Land Rover never missed a beat.

Land Rover Eco-challenge on the Alpine loop
Land Rover by paul talley, on Flickr
Land Rover by paul talley, on Flickr
Land Rover by paul talley, on Flickr
Land Rover by paul talley, on Flickr
Untitled by paul talley, on Flickr


The only problems we had was we lost a bolt in the rear sway bar arm and the ever constant Land Rover power steering box leaks. On the sway bar, my guess was that it was left a little loose when the lift was installed right before I got the truck. Luckily, a ⅝ inch hitch pin fit perfectly and we made it home with no problems. On one stretch of hwy we even got 14mpg!

Fixing the sway bar (don't worry the jack is only unloading the suspension and not holding up the truck!)

Land Rover by paul talley, on Flickr

Over the past year I have spent countless hours and way more money than I intended making this Land Rover a reliable road trip warrior. This trip proved to me it was all that and more!

Final Millage count
Untitled by paul talley, on Flickr
 
Last edited:

preacherman

Explorer
Due to some major life changes, now for sale in the for sale section here on expo.


Sent from my iPhone using Tapatalk
 

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