BMW Genuine Radiator Expansion Tank E46 E53 E83 17117573781

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Second one, 3.5 mm width, 22 mm id: This fits the heater hoses, plus the smaller of the two fittings at the bottom of the expansion tank, so i think that makes 5 per car. One of the primary areas of issue for the BMW E46 cooling system is the expansion tank. This is actually a very common issue on most BMW’s up until the late 2010s due to the material used for the tank itself. Both the BMW M52TU and M54 used a plastic expansion tank that had thin walls and was prone to damage. If coolant pressures within the tank reached a particularly high level, or if the tank has been overfilled, they have been known to explode in some cases. Good diagram of the hoses (someone else already posted the diagram, but here's a url anyway) is at: Doing the same job. That tank was beyond difficult to remove - I thought it was glued. Looked thru every post, you tube, I could find. Still nothing that tells

The difference in the aluminium tank was that the flow from upper connector was being pushed directly into the tank. This led to a situation where: Second one, 3.5 mm Width, 22 mm ID: This fits the heater hoses, plus the smaller of the two fittings at the bottom of the expansion tank, so I think that makes 5 per car. Installation meant some modifications: I drilled two holes into the plastic parts under the expansion tank, and used few screws to connect the new tank. An OEM replacement expansion tank is the best choice as while they are known to fail near the 100,000-mile mark, you’ll know that an OEM replacement will last equally as long. Another option would be to upgrade to an aluminum BMW E46 expansion tank. Reputable manufacturers like Mishimoto make an aluminum alternative to the OEM expansion tank and they are unquestionably stronger. With that being said, they are also significantly more expensive. Since the main belt and pulley assembly is responsible for so many vital systems, it is extremely important that it stays well maintained. The primary belt is guided by a pulley that contains grease to keep it lubricated. Typically this grease dries up around the 60,000-mile mark. When that happens, the belt can either become misaligned, slip off, or snap. At that point, you’ll be without power steering, an alternator, or a cooling system. E46 Belt and Pulley Failure SymptomsThe job of a thermostat is to regulate the flow of coolant through the engine by opening or closing a valve in response to changes in temperature. When the engine is cold, a thermostat remains closed to allow the engine to warm up faster. As the engine gets warmer, a thermostat opens gradually to keep the engine at a consistent and safe temperature. It will open all the way if the engine is overheating or the engine temperature has gone beyond a certain threshold.

Do not remove the expansion tank cap while the engine is hot. Coolant or hot steam may escape and will scald you. To do any work on the cooling system, wait until the engine has cooled off. I thought this is unbelievable, why, how is this thing (tank) still in here? Pull, Pull and wiggle, pull some more! Man. How to pry it off from the lower connection? Nothing fits to do that, Pry bar from the frame to the bottom of the tank almost works. Remember the slow and easy pulling, you will break the thermostat in the bottom if you man-handle it. I think it's like an egg shell, touch it and it will break.

E46 M3 Aluminum Expansion Tank by Moroso

This issue is very similar to the water pump failure problem that we discussed above. Failing thermostats have been a problem for BMW 3-Series since the E30. While it is one of the most common cooling system components to fail on BMW E46s, they don’t usually fail unexpectedly. Most of the time, BMW E46 thermostats fail at the expected intervals of around every 60,000-75,000 miles. Reinstall the coolant level sensor electrical connection. Make sure it is properly routed under hoses so the tank does not pull on the connection when installed. When you get this completed, assuming it works, could you please give details of location. with measurements, of the bung on the Moroso aluminum tank? I'm assuming you'll simply replicate the location from the OEM plastic tank to the aluminum (pronounced AL-U-MINI-UM for our British brethren) Moroso tank. This rids me of another fail point (split OEM tank) on the race car. Radiator part number 17119071519 (depending on the brand be sure to get a proper adjustment screw for manual or automatic transmission) These next pics show...that the expansion is simply "Hung" on piece 10, with bottom hose connections snapped into place.

As with any significant cooling system repair, it is also important to bleed the cooling system following the replacement of your E46’s expansion tank. If you don’t bleed the system, air bubbles can get trapped, causing excessive heat and pressure to build, leading to potential damage to the system again.

As an overview, the process of replacing the pulley includes the following: remove the four expansion rivets from the intake air duct, remove the intake air duct from the radiator support, remove the radiator cooling fan shroud from the vehicle, and extract the alternator drive belt (it is important to also mark the direction of the belt’s rotation). With the engine running, loosen the bleeder screw again. You should get more air bubbles coming out until there is a steady stream of coolant being pushed out of the bleeder hole. Tighten the bleeder screw.