One other weird thing.. All of the coolant I have seen to date just seems to be rusty water. Is that what Dex-Cool looks like when its gets old (I assume thats what's in there)?

 

So you know you have a coolant leak on the head gasket to the outside. That could actually be good news insofar as it seems less likely that you have a cracked block. I wouldn't assume that the leak only goes outside because that leak is to the space between the deck and heads and if it is bubbling out it is probably interacting with exhaust gas (it is getting some exhaust gas pressure). So I'd go ahead and either find a shop or order a head gasket kit.

The head gaskets keaking, alone, do not cause overheating. The lack of coolant causes it, along with the air in the system resulting from a lack of coolant. Air blocks coolant from circulating properly and gives room for water steam to separate from the coolant. That makes more pressure and etc.

The temperature is read from a sensor on the front center of the engone, so if it is shooting up when you start moving I'd say there is a water circulation problem. It is probably air in the system, but the impellers on our water pumps are super small... I wouldn't worry about that until after you replace the head gaskets and fill up with coolant. It might go away.

Best,

Charlie V

 

Dexcool does look like orange water.

 

I knew that DEXCOOL was orange. I guess orange + rust = rust color? Wait, if this an aluminum engine, where is the rust coming from?

I bled the system so there shouldn't have been any air in the coolant, right?

Ok, so my next step is Head Gaskets? How do I figure out if the heads are salvageable and test the block? If its more than a head gasket then its LS time. I figure gaskets and bolts are going to be about $200.

 

pull the heads you will find that one cylinder is trash, that is where the rust is coming from.
Your block and heads are aluminium, so unless you have the worst water impeller in the world, you have a bad cylinder.
rust is cause by iron or steel, the only part of your cooling system that iron or steel is the water pump impeller and the thermostat.

 

If an LS is in your plans, GET ONE... put the HG's on the rover engine and sell it to pay for the LS, then post a detailed how to and be a legend on the forums!

I haven't had Dexcool in my engine for so long I can't recall what it looks like except straight out of the bottle; sorry I missed your (OP's) reference to a rusty color. Dexcool can congeal and do all sorts of odd things but I don't know what causes it to turn rusty colored. EDIT: I googled it and found "Dex-Cool is a normal red, however, when not completely filled, when there is air in the cooling system it turns into a nice rust color and gets a tad thick."

You can do the HGs on a weekend with some basic tools, with the engine in the truck (actually, in the truck you need tome little joints to attach to your sockets for the back bolts--available at harbor freight or any tool place). 200 bucks should just cover it including the new head bolts, plus maybe some new fluids. If you are going to all of that trouble you might consider converting to green antifreeze. DexCool has some great properties but in an older rover engine (which is prone to head gasket/heating/malaise), the green stuff might be better--I've used it in my rover (for at least a decade) with no issues.

 

dexcool is light orange/ pinkish

 

Hmm... If take all of the trouble to replace the HG and that is all that is wrong, I might as well drive it for a while. In that case, would have purchased the car and gotten it on the road for about $1000, plus some routine maintenace from DiscoMike's list. I guess I wouldn't feel right selling someone a motor that may or may not work, unless I at least drive it a bit so I can accurately represent its condition. Do you think swapping the HG will add more than $200 in value? Right now it could be sold for someone's core charge turn in at least.

I guess to summarize, if fixing the head gaskets isn't enough to fix the engine, then why bother with them? Then engine would (could) still be screwed.

About coolant. I get that DEX-COOL is bad (Dex Cool). It is an Organic Acid Technology (OAT) formulation. The green stuff is Silicate formulation. Has anyone tried Hybrid OAT coolant (G05 / yellow)? The problem with silicates was supposedly water pump and pump seal wear. Although I guess a low silicate green coolant (like Zerex Original) would be better than old school green stuff (High silicate formulations)?

Anyway, speaking of water pumps. My current theories on why my truck is overheating are: corroded/eroded water pump impeller, blocked coolant passages, or cylinder pressure entering the coolant circuit and reducing/stopping pump flow.

Blocked coolant could be anywhere, since DEXCOOL was in play. Radiator, block, pretty much anywhere. This is partly why I'm trying to get the invoices from the mechanic I got the truck from, so I can see what was replaced. I can see all of the coolant hoses are new, they are nice and shiny and still have the Land Rover stickers on them.

How can I test oil pressure? Is that readable via OBDII or do I have to buy and rig up a gauge? No oil pressure light currently, but it would be nice to know what I am dealing with.

 

Just get a cheap screw in mechanical gauge. There's a couple ports on the side of the front cover that you can screw in to. There are block off bolts on them that you'll have to remove.

 

I bought a very nice 2003 for 900 bucks because it had an exhaust only head gasket leak. Most people get a couple of estimates on HG repair from a shop and just run away from Discos. The engine might have value to someone in the know, but not knowing for sure whether the block is cracked, I doubt you would get much for it.

I have used Prestone for years without problems (green).