[paraklas]

Just bought a 01 330ci convertible. Was only driven 30 min a month for 2 years. Dude was topping off coolant with water. Starting to notice small pool on ground so I'm going to replace hoses, thermostat and expansion tank. As well as flush the radiator.
Question: Should the radiator just be replaced? Also, if I flush. Can I do this with water or should I use a flush cleaner?
Does anyone know if someone makes an expansion tank that doesn't crack?😅

The genuine BMW ET will probably outlive the car if you replace it now. I replaced mine a few months ago after 15 years of usage as PM.

• don't forget the expansion tank cap. Personally I use the stock 2.0 bar cap, again genuine.
• clean aluminum mating surfaces on the engine
• Perhaps do the expansion tank bracket, especially if the expansion tank is stuck on it
• New crush washer for the engine block drain plug
• new bleeder screw (should come with the new upper hose kit)
• lubricate o-rings with undilluted bmw coolant, makes them slide in place easier
• lower radiator hose has temp sensor, get a new o-ring for that sensor
• if the radiator is still the original, check it at the lower section if it's still straight. Also if the hose ends of the radiator feel that are about to crack, replace the radiator too.
• What about the water pump? Ever changed? These have the bearing go or leak through the o-ring
• hard coolant lines below intake? They also tend to rot and leak
• auto or manual? different radiator drain screw that should be replaced too
• Read and perform the venting process precisely to avoid overheats and other issues.

 

[paraklas]

^Was about to say this.

It is actually less time consuming and less effort to take out the bracket with the expansion tank as one instead trying to separate them while on the car.