Cracked radiator/ Heater blowing cold

[derbycityjoe]

Just developed a crack in the plastic (drivers side) of the radiator on my 2002 4.6is .. didn't realize it until the heater started blowing cold and saw steam coming from under the hood .. water Guage showed normal, so I drove the half mile from the off ramp home.. what am I looking at for repair?

[David.X5]

If you overheated the engine, the damage could be substantial. And there is a question of why the radiator cracked - lots of possibilities including a leaking/failed head gasket causing over-pressurization.

Without considering any of that, the actual radiator cost isn't too bad.

The Behr version of that radiator (I have installed it without problem) is available for about $210 online. A couple gallons of BMW coolant is another $50. Not a bad DIY, but probably 2 hours for a shop to replace and refill it if you are paying someone. Depending on where you are on your mileage and maintenance, may be a good time to replace some radiator hoses, thermostat, etc. which will increase parts cost.

[bcredliner]

Not that unusual for a radiator to crack when there are no other issues especially if it is the original radiator.

If you are concerned that some other problem caused the radiator to crack and depending on how bad a leak you have, you could refill the system with water to see if it runs without overheating. How many miles on your X5?

[lo_jack]

R&R the radiator is not a hard job. Just make sure you didn't overheat the motor irreparably because of that. The radiator itself is somewhat pricey. People have spotty success with off brand units.

[derbycityjoe]

It has 130000 miles... I'll try filling it with water and troubleshooting that way..curious if the thermostat will open and the heat will.kick on

[derbycityjoe]

How do iknow Iif the engine overheated ?

[David.X5]

Use jugs of distilled water from the supermarket and not tap water to avoid introducing minerals into the system. I did a bunch of engine work on mine at the 140k mile mark (still had good looking blue coolant in it) and there was zero mineral deposits and the engine internals showed no signs of corrosion.

[David.X5]

Hopefully when you start it up again you won't see new problems - the fear is something like warped heads which would cause problems like leaking fluids, smoke in the exhaust, poor compression, engine roughness, hard start, etc.

[derbycityjoe]

Roger that.. thanks ! Super cold here today.. had to ride my BMW adventure to work this morning.. going to wait till I'm off friday and it's warmer- I'll post results..

[g300d]

As I understand your coolant temp never went up, and you only noticed the crack when the heater started blowing cold and some steam started coming out?

If so I doubt you damaged anything.

I would consider overhauling the entire cooling system while you are there. Radiator, distribution plate, cooling system and heater hoses, expansion tank.

It might seem excessive, but it has been my experience on an 03 4.6is that when I replaced leaking hoses, the expansion tank started leaking soon after. After the tank, the radiator distribution plate started leaking.

Do check your fan clutch too while you are there. On both a 4.6is and a 3.0i leaking but not totally dead fan clutches have caused elevated average coolant temps for me. Replacing clutches brought average coolant temps down significantly on both.