overheatin issues, need help / advise please
 

Hello guys and gals, i am calling on the collective knowledge of this forum for some help. i have an 03 disco that started overheating shortly after i purchased it. Initially i had the slushing sound under the dash due to what i believed was a due to coolant leaking from the throttle body heater. Changed that and everything seemed fine but then it ran hot with steam coming out of tank and needle pegging out. got it home, bled system using vacum airlift tool. Truck ran fine for awhile but started overheating again. I believed it was the head gaskets as i read on here that they are a common problem and i also observed what seemed like a small coolant leak from the rear portion of the drivers side head between head and block. i replaced both gaskets, water pump and thermostat. The heads were checked at a machine shop and was told they were not warped however they did not have the jig to machine them. after getting it all back together, the truck still over heats. :mad:. The coolant system boils over and no heat from dash. I pulled all plugs and put each cylinder to TDC then pressurized with approximately 140psi from air compressor. No air or liquid was expelled from the coolant tank. whenever i use the vacuum tool, the system hold vacuum forever so i cant pinpoint a problem that way. When i run the truck, there are bubbles in the tank and coolant is pushed out. I ran a chemical test which indicated compression leaking into coolant system but i have no clue as to where it can be from. I am prepared to pull the engine out and disassemble but how can i locate my real problem? my other dilemma is that once the engine is out, do i rebuild it all together or should i look for a replacement? which way would be cheaper?

The no heat from the dash sounds like low coolant. The D2 normally runs coolant thru the heater core 100% of the time, there is no on/off valve. Bleeding can be a real problem in these. Do you still have the water under dash gushing sound?

A cracked head or block can introduce stuff into the the cooling system, and shoot temps high, make hoses rock hard. However, I'm not sure how a cracked block behind a cylinder sleeve might work at TDC when you are testing. With engine torn down you can do a block pressure test with plates to bolt off various ports. Of course now the coolant cap needs to be 100%, if it is wimpy you can overheat. Usually this is followed with coolant loss.

Be real sure you examine the serpantine belt route twice. A paper towel or plasic trash bag should get pulled against the grille, not blown away.

Some guys put a green dye in coolant, then look for green flecks on the plugs.

We have had postings about stats that were not oem not opening up. The stat is different sort of beast. If you wanted to test it out of the truck, you would pour hot water in the top center opening (you'll see small holes on a disk). When the main stat reaches temp, the water would pour out the bottom fitting. An aftermarket 180F stat is also available.

Here is the water route from the RAVE manual.

i double checked the belt routing and it,s good. there is no more water fall noise under the dash. Is there a common spot where cylinder sleeves may fail?

see posted by one of our members showing what is involved in a block pressure test.

It is said that HG leaks are more common on the outboard cylinders, and that inside cylinders when leaking could be cracked block. I'm not sure what the percents of chance are. Blocks can be shipped off to be reworked and resleeved with "top hat" liners, or redone blocks can be purchased. There are posts about each of these paths, which are more than the cost of a used D1 and some D2s. If cracked block you are most likely looking at another block.

Then there are the $199 u-pull-it engines from a boneyard, pretty well figure on HGs as a minimum for those. Some boneyards have short warranty.

It is possible to warp test a head without machining it, there are specs in the overhaul section of the RAVE, .002 inch for flatness. So shop could have checked it and found it within spec.

And there is always Kseal, which is a block sealer. A tool of the "must get home from this road trip" or the "I've tried everything else" situation. And perhaps the lower temp 180F soft spring thermostat might operate the engine below the temp where the crack opens up.

And the existing block can become part of the man cave.

also see JE Robison Service — the blog: The last word on Land Rover liner failures - I hope!

where can one buy these " top hat " liners and rebuild parts at a descent price?

Also i found out that the previous owner used the block seal trick since tons of the stuff came out of the radiator when i was fixing it. may need to replace raiator since pro flush cost isnt cheap so may as well just replace

looking for a place to buy engine rebuild components or does anyone know of an engine swap kit say for a chevy engine or something along those lines.

what about a 4.6L range rover block or complete engine? any ideas if it would work?

If you spend some time searching on line you can find a complete 4.6 for around$3000. Just spoke with one of out members today and he found one, still in the totaled Disco with 23,000 miles.
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