Installed an UltraGuage in my new-to-me D2, and I'm seeing some elevated temperatures. So, I'm starting my diagnostics and repairs process. I've ordered a 180* thermostat from Rimmer, and I'm trying to bleed the system to see if there's any air (I've also got some water sounds coming from under the dash, though no leaks that I can see).

Using Disco Mike's process, I raise the coolant tank, and remove the bleeder. As I unscrewed the coolant tank cap, quite a lot of coolant came out through the bleeder. I put a catch basin under it and it eventually stopped. There awas very little coolant in the bottom of the coolant tank. As soon as I started to put some coolant in the tank, coolant came out of the bleeder, so I re-installed the bleeder screw, coolant cap, put the tank back in its place, and started the engine and warmed it up. Coolant tank was filling up from coolant coming through the small return line that comes from top driver's side of the radiator.

Does this sound right? I've hardly put any coolant in, so now I'm worried there's not enough.

Both fans appear to work (clutch fan doesn't spin freely, spins in right direction, and aux fan comes on normally). I get heat in the cabin, though strangely not always from the centre drivers side vent.

I just bought a temperature reader so I still need to check various parts of the rad.

 

When you are bleeding the system you don't want the flow of coolant to stop

1) You need to fill the reservoir above the max fill line.
2) Then lift the reservoir and while you hold the reservoir unscrew the bleed screw. I unscrew the bleed screw all the way and let in drain really good for about 5 second, then tighten the screw while the coolant is still coming out. You don't want the coolant to drain to the bottom of the reservoir. Just about an inch under the fill line.
3) After bleeding, top the reservoir up to the max fill line and place the reservoir back where it goes.
4) Turn your heater up to max (fan and temp) and let the car warm up until the thermostat opens a a few times.
5) Let it completely cool down and fill the reservoir back up to the fill line if the coolant level dropped any.

 

Exactly. Also make sure that the stream coming out stays constant. You might have air that takes some time to get out. If the stream coming out shoots up then drops down and shoots up again, give it more time & coolant.

 

Well, I've been opening the bleeder each morning, then closing it and topping off the coolant. Today I noticed that the bleeder screw was actually leaking through the centre of the screw....and lost a bit of coolant in the process. I quickly ran over to my local LR dealer and bought the whole upper hose assembly (couldn't get just the screw, of course).

One of the very few occasions that my local dealer had a decent price for something, so I'm not too put out.

Since the truck as over 200,000km on it, I'm just going to do the whole system over. 180* t-stat should be here in a few days from Rimmer, ordered a water pump and Hayden fan clutch from RockAuto, and a radiator from AutoPartsWay.ca. I'll source an early fan locally...I prefer the older two-piece clutch fan design rather than the integrated unit. Will also have new hoses, and will clean out the expansion tank while everything is apart. I can see a little sludge in the bottom so I think the POs have mixed coolant in the past.

I hate doing big(ger) repairs in my driveway, though. My neighbour has his townhouse up for sale and I'm sure is not happy about me doing my shadetree thing in our shared driveway!

 

Give this a try.
Unclip the coolant tank.
Raise it as high as it will go and put some wood or rags under it to hold it up steady.

Warm up the truck for 10 minutes.

Take off the coolant bottle cap.

Rev the engine to 2000 RPM.

Is coolant coming out?

Stop.

You probably have a blown head gasket.


Is coolant not coming out???

Then keep the bottle up there.
Engine at 1,800 RPM for 10 minutes with heater on HIGH.

OK, now come back to idle.

This gets ALL the air out.

OK, now come back to idle.

Then add coolant up to the fill line.
Put the cap back on.

Engine off.

Put the bottle back into the clips.

And enjoy the ride.

No one agrees with my bleed method.
but, this is HOW a Discovery I works.
A Discovery I works as it self bleeds as it drives.

The Discovery 2 has the coolant bottle too low.

Good luck.

Don't open the bleeder screw.
It will break.
And I don't think that it does a good job anyway.

 

Sounds like you are making the right call with all the new stuff if you found gel/sludge stuff in your fill tank.

Did you get the new style bleeder setup? (new one has the bleed screw in a plastic T; old one has the bleeder in the hose) FYI- The new style is a way better setup.

You might want to replace all of the old hoses instead of just the upper hose. Here is the set from Atlantic british to show you which ones you still need if you decide to get them.

Land Rover Discovery II Hose Kit: Land Rover Parts & Accessories From Atlantic British

Also, you might want to back flush the heater core to make sure none of that Sludge blocks up your heater. If the heater core goes then you really have a big job on your hands (the truck is built around it).

 

Yes, it has the plastic T with the bleed screw. However, I'll likely replace this with a metal T, tap a hole in the top and install a small valve. That way, I can attach a clear hose and bleed it in a cleaner fashion.

Thanks for the tip about the heater core - I'll add that step to my plan. I used to have a Porsche 944, and the saying goes that the engineers started with the heater core and designed/built the rest of the car around it. I believe it, too. I stripped the car out for racing and there wasn't much more than the shell before I got that sucker out!

 

Use a long bungie cord to loop under the coolant reservoir and hang it from some of the holes in underside of the hood to keep it elevated while you are bleeding the system.

Make sure to replace the hose that is really two hoses that are smaller heater hoses at the firewall that go to/from the heater core. The hose come as one unit, and the two hoses cross over each other between the connections on the cooling system at the engine and the pipes coming out of the firewall where they connect and have a connector of plastic or some other material that hold them together as one assembly. I little lubricant of some kind is helpful in getting these hoses back on the pipes. Careful removing the old hoses from the pipes coming out of the firewall. You do not want to kink these pipes, it can make it hard to get a good fit back on with the new hoses. For this reason I recommend the screw-type clamps here, in case these pipe become out of round the lease bit when removing the old hoses (Yes, I did it, and had to replace with screw clamps to get it to tighten up around the oblong pipes after a leak.) I like the screw type clamps for all my replacement clamps as well.