X5 E53 ENGINE OVERHEAT

[jakpan2004]

Hi, just bought my fairly use X5 E53 3.0i and it started overheating from day 1, I have changed the Expansion tank which was leaking from the valve, fan clutch I discovered was faulty and was change, Thermostat housing was leaking and changed. I have bled the cooling system according and the engine is still overheating. What could actually be the problem any assistance will be appreciated.
I even had to remove the thermostat from the housing hoping the hot climate may compound issues, it only slowed down the heating time against when it was installed. The radiator is not leaking and it was flushed. will there be a difference to change the radiator from single vane to double vane

[UCrewX5]

Has the water pump been checked? That is the next thing I would replace.

[motordavid]

Originally Posted by UCrewX5

Has the water pump been checked? That is the next thing I would replace.

...and make sure your coolant fill is the rec'd 50-50 coolant
and distilled water.

We have run our '01 3.0 is some serious warm summer temps, in
hours of stop and go driving and the needle has never budged
from straight up, dead center. This isn't Nigeria, I realize, but
something is amiss...if no leaks, the water pump is the obvious
try, imo.
GL,mD

PS: you didn't mention whether or not your aux cooling fan is coming on; it should
on any kind of condition where your engine is warmed up and the ambient temps
are just "warm", imo. Without that aux fan to pull air across the radiator space,
you are fighting an uphill battle to maintain the engine's proper temp.

Oil "cools" the "bottom"/lower end of the engine and the circulating coolant cools
the "top" end of engine, to be poetic...but without the upper cooling, the entire
engine can get past the tipping point of proper operating temps.

[reg]

The 3.0i has a plastic propeller water pump. They usually fail around 90,000 miles. check or change it now because very bad things can happen it the engine overheats (HEAD GASKET)...

[jakpan2004]

Thanks Guys for the reply and suggestions. I have actually checked the water pump, the water is circulating while the vehicle is steaming, this you observe while bleeding the system. All this is kind of leading to the head gasket..
Question??? if the top head cylinder is affected by the overheating, what other signs can I expector observe apart from the over heating. There have being suggestion from friends that the top is gone or the gasket and the top head cylinder is damaged

[jakpan2004]

Originally Posted by reg

The 3.0i has a plastic propeller water pump. They usually fail around 90,000 miles. check or change it now because very bad things can happen it the engine overheats (HEAD GASKET)...

My X5 is 98,000 miles, I will physically check if the plastic propeller has broken vanes

[jakpan2004]

My observation here is that, pressure is pushing the water out of the radiator, with observation of bubbles from the system, as if the water us boiling or steaming from inside the engine.

Originally Posted by motordavid

...and make sure your coolant fill is the rec'd 50-50 coolant
and distilled water.

We have run our '01 3.0 is some serious warm summer temps, in
hours of stop and go driving and the needle has never budged
from straight up, dead center. This isn't Nigeria, I realize, but
something is amiss...if no leaks, the water pump is the obvious
try, imo.
GL,mD

PS: you didn't mention whether or not your aux cooling fan is coming on; it should
on any kind of condition where your engine is warmed up and the ambient temps
are just "warm", imo. Without that aux fan to pull air across the radiator space,
you are fighting an uphill battle to maintain the engine's proper temp.

Oil "cools" the "bottom"/lower end of the engine and the circulating coolant cools
the "top" end of engine, to be poetic...but without the upper cooling, the entire
engine can get past the tipping point of proper operating temps.

[UCrewX5]

Originally Posted by jakpan2004

My X5 is 98,000 miles, I will physically check if the plastic propeller has broken vanes

If you have the water pump off then you might as well go ahead and replace it.

[alpac]

Originally Posted by jakpan2004

My observation here is that, pressure is pushing the water out of the radiator, with observation of bubbles from the system, as if the water us boiling or steaming from inside the engine.

Several possible reasons but I would try to rule out a possible blown head gasket first. Do you have white smoke from your tail pipes? Check your oil dipstick and look if the oil has a milky aspect from being contaminated by water. If you have one of these conditions then stop using the car and get a compression check at a garage.

[Weasel]

The waterpump is easy to remove, only 4 screws on the pulley and 4 nuts on the pump. But if it did overheat bad enough to cause head gasket problems what usually happend is the higher expansion rate of the aluminum head stretches the head bolts and pulls the threads from the block. What we do to test for that at the dealer is pull the valve cover and try to re-torque the head bolts. If they have a problem, they will strip out rather than tighten.