Recently purchased used 03 Discovery II mechanic special.
Previous owner stated bad head gasket job, and it would not hold coolant. I had it towed, got it started, small leak at waterpump.
Replaced the waterpump, hoses, and thermostat. Drove fine for 3 weeks.
Then one day it overheated, i pulled over and noticed coolant in tank bubbling and streaming out small tube.
I let it cool down, re-bled, ran it idle for 20 min, no overheating, so continued driving.
5min later, same overheating again. repeated cool down and bleeding twice to get it home.
Once home, another overheat, and then white smoke out the tailpipe.

I most likely will need head gaskets replace, although I would like to know...

What are the main causes of coolant bubbling in expansion tank...???
combustion gas in coolant ?
from leaking head gasket ?
slipped liner?
cracked block?
or something else that causes bubbling coolant in tank...
Please help...

...and glad to be back in Rover Land again

Fault Codes
P1300
P0306
P0135
P0155
P0130
P0327
P0302
P0301

 

Bubbling in the cooling system is usually the sign of a blown head gasket. Sorry for the bad news. It's actually a very common failing on the Rover V-8, and has been for decades. It's not the end of the world, and it can be repaired.

It's possible to have a head gasket failure that doesn't leak much at idle, but then blows lots of gasses into the coolant under load. It's also possible that you have a cracked head, although that isn't as common. Still, when you get the heads off, get them checked for cracks and check them for warping too, since they'll be off the car anyway. You can also check your liners at the same time.

Good luck,
Scott

 

Overheat with white smoke is pretty much a head gasket, to get the white smoke you need coolant in the combustion chamber. More coolant that you generally get with a cracked block, so the "Good News" is it is likely a head gasket.

Not a hard job but time consuming.

 

Thanks, I'll report back once i get the heads removed...

 

...well started the HG job today.
Already signs previous job was not proper...

 

Lord why do people do that kind of stuff with RTV??? What a mess!

 

So. MUCH. RTV,

I wonder it blocked the intake and maybe there was is some floating around the block causing your overheat?

 

Is that a broken bolt? The would explain (but not justify) the mess of RTV.

 

...down to the lower intake today.
The lower intake bolts on the passenger side were not torqued properly, two of them did not require a socket(only hand tight)
When I moved it forward to disconnect the fuel line, I heard coolant drip to the ground.
Also previous mechanic left a small bolt and tire cap underneath the back of the valley gasket :|
Is it normal to have coolant in this area during removal...?

Tomorrow, rockers, SAI, exhaust and heads. Front SAI removal was smooth, the rear spinning. Will need to hold inner to tackle the rear tube.



Gift from previous head job

 

Get rid of that factory thermostat while you are redoing everything.