Coolant leak from left side of engine block running down oil pan.

It's unlikely that there is a freeze plug in that area. The most common sources of coolant leaks on BMW E46 3-Series models are the expansion tank and the radiator. However, there are a few other possibilities that could cause a leak in that area:

1. Heater Core: The heater core is located inside the dashboard and circulates hot coolant to provide heat to the interior of the car. If the heater core is leaking, coolant can drip down onto the motor mount.
2. Coolant Pipe: There is a coolant pipe that runs along the left side of the engine and connects the engine block to the heater core and radiator. If this pipe is corroded or damaged, it can leak coolant onto the motor mount.
3. Head Gasket: A failing head gasket can cause coolant to leak externally from the engine. While this is less common, it's worth checking to see if there are any signs of coolant leaking from the head gasket.

It's recommended to have the coolant system inspected by a qualified mechanic to determine the source of the leak and to make the necessary repairs.

You will have to clarify behind the oil pan. Front of engine towards fan. Rear of engine transmission side. Or above the pan towards engine side. If there is coolant leaking from behind the engine (between the engine and trans) and is not running down from above eg head gasket or hose connection, chances are good that there is a frost plug leaking on the rear of the block.

Most radiators have a drain plug on the bottom tank the engine block also has a drain plug . Remove the radiator cap ,open both drains ,let all the coolant run out, if there is no radiator plug remove the lower hose , remove the heater demister hoses, with the heater control on hot flush out all the coolant from the heater radiator. with a garden hose, till the water runs clean, tighten the radiator plug or re fit the hose,put a garden hose into the radiator and flush out till the water at the block plug runs clean ,refit the heater hoses, refit the block plug, fill the radiator from the hose leave the cap off , If it has a overflow tank clean and flush it. start and run engine for 5 minutes top up radiator if needed . stop engine and drain out all water. most important that all old coolant is drained out, only buy the best coolant you can . If you make up your own use only distilled water. keep some to top up with never mix with another brand. Fill radiator with coolant top up over flow tank, run engine top up coolant as needed, refit radiator cap run for another 10 minutes check for leaks,

It could be due to age. Split hoses aren't uncommon.
However, it could be due to either a radiator blockage or a cylinder head problem - which is allowing exhaust gases to find their way into the cooling system via a leaking head gasket. When this happens the cooling system becomes pressurised by the exhaust gases.

To check if your radiator is blocked, run the engine until it is hot. The coolant goes into the radiator via the top hose and into the engine through the bottom hose.

Carefully feel the top and bottom hose. If the bottom hose feels much cooler than the top hose, then that indicates a radiator blockage. If the bottom hose feels 'flat' and 'squashed' that is another indicator - though it also can point to head gasket problems.

To check if there are head gasket problems, first check the oil on the dipstick. If it is a 'creamy sludge' then that indicates coolant has found its way into the lubricating system via a leaking head gasket.

Also remove the cap from the raditor expansion tank (where you fill it with coolant/water). Is there any sign of oil/sludge in the expansion tank? Another sign of head gasket problems.

With a COLD engine, remove the cap from the radiator expansion tank and then fire the engine up. Watch the coolant as the engine ticks over ... at first bubbles will appear as air in the coolant escapes. The bubbles should stop after a few moments as the engine warms. If the bubbles continue -or there is 'violent bubbling' that's teling you there is a head gasket problem.

I presume that your car hasn't been overheating or 'running rough' at times, as you haven't mentioned that. Overheating and 'running rough' can also be symptoms of head gasket problems.

All being well .. no radiator blockage or apparent head gasket problems, it is more than likely that the hose burst due to age/mileage.

Hi!!
On the bottom of the radiator, there is a drain valve, just open it and drain fluid into a container, if you want faster drain, remove bottom radiator hose.
NOTE: DO NOT OPEN SYSTEM WHEN HOT, COOLANT IS POISONOUS FOR PETS, KEEP IT AWAY FROM THEM.
Good Luck!! Rate this post!!

hello. on the drivers side of radiator is a drain. here is a picture and the instructions for draining the coolant out.

Install a tube on the radiator drain. Place the end of the tube in the drain pan.

After the engine cools down, remove the radiator cap.

Completely open the radiator drain ****.

Allow the coolant to drain from the system until the flow stops.

Place a drain pan under the block drain hole plug.

Remove the drain hole plug from the engine block.

Allow the coolant to drain from the block until the flow stops. There may be more drainage from the radiator at this time.

Install the block drain hole plug.

Close the radiator drain ****.

Volvo 1990-1998 Repair Guide
Radiator - REMOVAL & INSTALLATION
Perform this work only on a cold engine.

1. Disconnect the negative battery cable.
2. Set the heater control to MAX heat.
3. Remove the expansion tank cap.
4. Place a suitable drain pan into position. Open the **** on the right-hand side of the engine block. Fit a hose to the **** to collect the coolant. Open the radiator draincock.
5. Close the drain cocks when the coolant is completely drained.
6. Remove the cooling fan.
7. Remove the cooling fan shroud.
8. Disconnect the upper and lower radiator hoses

9. On vehicles equipped with automatic transmissions, disconnect the transmission oil cooler lines at the radiator. Plug the lines immediately. Catch the spillage from the radiator in a separate pan.

10. Some vehicles are equipped with a temp sensor on the drivers side top of the radiator, if equipped remove the connector.
11. Remove the radiator retaining bolts and brackets.
_
12. Remove the radiator assembly from the vehicle.

On 850/C70/S70/V70 models, the radiator comes out the bottom of the vehicle.
To install:

1. Place the radiator into position and install the retaining bolts.
2. On automatic transmission vehicles, connect the oil cooler lines.
3. Install the fan and shroud.
4. Install the lower and upper radiator hoses.
5. Connect the expansion tank hose. Make sure that the overflow hose is clear of the fan and is free of any sharp bends.
6. Fill the cooling system through the expansion tank, with a 50 percent antifreeze, 50 percent water solution.
7. Connect the negative battery cable.
8. Run the engine until normal operating temperature is reached.
9. Bleed the cooling system.
10. Check for leaks.
11. Top up the cooling system, as required.
12. Replace the cap.
13. Check and top up the automatic transmission fluid level.

Hope thats help (remember comment and rated this).

We have had some similar problems with some BMW's,the last one we replaced the expansion tank.Before we attached the upper radiator hose to the radiator we filled the engine with antifreeze through the hose.Install the hose and fill your expansion tank to the proper level and run the engine to operating temperature.

The water (coolant) in the expansion tank will rise and fall with the engine temperature. What the expansion tank does is collect and return coolant to and from the engine. When the engine warms up the coolant gets hot, builds up pressure and opens up the radiator cap. The coolant then goes into the expansion tank. Now when the engine cools down the pressure drops in the cooling system and the pressure drop (vacuum) pulls the coolant back into the engine via the radiator cap. The radiator cap allows the cooling system to build up pressure and by doing so increases the boiling point of the coolant, but when that pressure exceeds the caps rating the cap opens and the coolant goes to the expansion valve. The cap has another part to it that when the engine cools down and a partial vacuum is created in the cooling system a "valve" in the radiator cap opens and allows the coolant to be drawn back into the engine. I would look at your radiator cap to see if any gunk or build up is on it, and check the rubber gaskets for cracks. It's easiest just to replace the cap because they are inexpensive and easy to replace (2-10 dollars). The expansion tank should have two hoses on it. The one on the bottom comes from the radiator and the one on the top (possibly part of filler cap) runs down and is open to the ground. That way if it is overfilled or becomes overfilled it will slowly leak onto the ground. When and if you change your radiator cap, make sure the engine is cooled down, remove cap and start engine and turn heater to full blast, full heat. Leave the cap off and let it run until engine warmed up. This should burp out any air pockets that may have happened when coolant was changed. Also top off the coolant in the radiator while it is running. Hope this helps and good luck

there can be a yellow light in the cluster that looks like a small radiator or box with waves inside of it to indicate water. This light means that the coolant level sensor has detected a low coolant level. Typically the expansion tanks inside of these cars will crack from heat and age. A simple diagnosis is to check your coolant level and top it off. Do not forget to bleed it by unscrewing the bleeder screw found on the upper radiator hose while filling up the reservoir found on the right hand side of the radiator. once the coolant has been filled, tighten the bleeder screw back down but be careful not to over tighten. and finally screw on the expansion tank cap. run the vehicle to operating temperature and use a flashlight to inspect the engine bay for leaks. If there is a leak, it will need to be repaired. possible leaks are a cracked expansion tank, leaking radiator hoses, or a leaking water pump or thermostat.