Good Day Forumers,I'm a newbie and have already introduced myself at the newbies section - so I thought I'd stop by here and enquire a few things.I am rather new at this forum so I hope I have came to the right section to post my enquiry.Actually, I'm curious as to what the so-called "infamous" Expansion Tank in E46 is all about. I did take the liberty to search through this forum to find out about the expansion tank but so far most of the infos I got is that it needs periodical replacement, when to replace it, the costs of it, etc. etc.Perhaps I might have overlooked since there are plenty of threads in this forum - but I would really appreciate if there would be someone kind enough to help enlighten me on what is an Expansion Tank?** One more thing if you don't mind, does anyone know if there are any independent BMW workshops (maybe even those that are mentioned in this forum), that have their own website? I know it's "against regulations" to post URLs in this forum but perhaps (if there are any) - maybe you could just let me know the name of those workshops?MANY THANKS
Expansion Tank
- Thread starter jazz1011
- Start date
-
Click here to become an Official Member of BMW Club Malaysia Download Form
Mouse
Club Guest
- Joined
- Jan 1, 2006
- Messages
- 1,679
- Points
- 38
i think he's asking the fuction of the expansion tank. from my understanding, its a reserve tank for your radiator, it flow and direct your coolant to your radiator acting like a topup spare tank. imagine if your radiator is very hot after long distance travel and needed more water after 'dehydrating' and there is no spare tank to conserve the water for him when he is thirsty. your radiator will eventually dry off and cause the engine to die coz there is no coolant circulation between your engine block to cool it. your engine gasket will be blown off and all your valve will bent after hitting against the piston. hehehehe, any sifu here, is my explanation correct, did i manage to con jazz?
Thanks a lot for the info, guys.
Well, one might be a short answer and another a rather detailed one - but it's better than no answer at all.
At least now, I have some idea on what this "infamous" expansion tank is - as some of you guys call it, lol.
Thanks again. I really appreciate your assistance.
Well, one might be a short answer and another a rather detailed one - but it's better than no answer at all.
At least now, I have some idea on what this "infamous" expansion tank is - as some of you guys call it, lol.
Thanks again. I really appreciate your assistance.
planta
Club Guest
- Joined
- Sep 17, 2007
- Messages
- 508
- Points
- 0
Under the expansion tank, there is a secondary thermostat and this thing needs to be replaced, if I am not mistaken at ~100k km and cost about rm250.
If the thermostat is jammed, it may cause the expansion tank to burst or leads to overheating issues.
planta
If the thermostat is jammed, it may cause the expansion tank to burst or leads to overheating issues.
planta
planta
Club Guest
- Joined
- Sep 17, 2007
- Messages
- 508
- Points
- 0
Hi Jarance, my best friend fix cars and his passion is BMW. I help him to fix cars or BMW on weekends for free, coz I am gear head I guess. The more you "touch" a BMW, the more you love it and I just had to buy one and did that in June 2007. Thus, I do my own servicing and maintenance for my E46 with the help of my friends.
Earlier this year, there was customer at my friend's work shop who had an overheated E46 318 1.9. The root cause was jammed secondary thermostat that also led to a crack at the expansion tank. He paid thousands to fix it coz as everyone knows, overheats leads to serious damage.
As for the expansion tank burst due to jammed thermostat while driving, I read about it in another forum. (UDMowners.com).
When I first bought my pre owned E46 mileage was 180k km, I changed the secondary thermostat too. After a month, I also brought it to a BMW service agent for a thorough check up. Another best friend is working there and the first thing he asked me to do since my milage is high was to change the thermostat. He said, he had seen many owners paid thousands for overheating due to the thermostat failure which only cost ~rm250 to change.
Hi Daniel. The expansion tank does not come with thermostat. It is sold separately, I changed the thermostat only as my expansion tank is still ok.
planta
Earlier this year, there was customer at my friend's work shop who had an overheated E46 318 1.9. The root cause was jammed secondary thermostat that also led to a crack at the expansion tank. He paid thousands to fix it coz as everyone knows, overheats leads to serious damage.
As for the expansion tank burst due to jammed thermostat while driving, I read about it in another forum. (UDMowners.com).
When I first bought my pre owned E46 mileage was 180k km, I changed the secondary thermostat too. After a month, I also brought it to a BMW service agent for a thorough check up. Another best friend is working there and the first thing he asked me to do since my milage is high was to change the thermostat. He said, he had seen many owners paid thousands for overheating due to the thermostat failure which only cost ~rm250 to change.
Hi Daniel. The expansion tank does not come with thermostat. It is sold separately, I changed the thermostat only as my expansion tank is still ok.
planta
planta, thank for clarifying the burst tank due to jam thermostat. basically, a thermostat when jammed in closed position will stop the hot water from being diverted to the radiator but circulated within the engine block and the water pump. In cool condition, the thermostat will be closed and water is recirculated within the engine block and the water pump. this will bring the engine to the optimum operating temperature in the shortest possible. As the water temperature heat up, the thermostat will open at a preset temperature and diverted the hot water to the radiator where the heat is extracted via convection (air passing thru the radiator via cooling fan).
If the thermostat is jammed, the consequence is that the engine will overheat and other part like water hose or plastic casing will give way due to the extreme high temperature. This will causes a rapid loss of coolant and absolute NO cooling medium for the engine. The consequence is that engine will lose power and visible sign of smoke will come from the engine bay. (gasket most probably blown due to overheating)
Many people will usually topped up the engine with cold water without letting the engine to cool down first. This will further caused the engine block to warp and add further damage to the engine.
Hence, DO NOT FILL THE RADIATOR WITH COOL WATER WHEN THE ENGINE IS HOT.
That why a lot people tends to spend a lot of money when the expansion box burst but have to do top overhaul due to engine warp or blown gasket.
If it any consolation, I seen that the E90 have the expansion seperated from the radiator. (just like the Japanese car)
If the thermostat is jammed, the consequence is that the engine will overheat and other part like water hose or plastic casing will give way due to the extreme high temperature. This will causes a rapid loss of coolant and absolute NO cooling medium for the engine. The consequence is that engine will lose power and visible sign of smoke will come from the engine bay. (gasket most probably blown due to overheating)
Many people will usually topped up the engine with cold water without letting the engine to cool down first. This will further caused the engine block to warp and add further damage to the engine.
Hence, DO NOT FILL THE RADIATOR WITH COOL WATER WHEN THE ENGINE IS HOT.
That why a lot people tends to spend a lot of money when the expansion box burst but have to do top overhaul due to engine warp or blown gasket.
If it any consolation, I seen that the E90 have the expansion seperated from the radiator. (just like the Japanese car)
Hey Guys,
Thanks a lot for all the great infos. Very much appreciated.
I wasn't wrong when I made the decision to join this forum - even though I do not own a Bimmer - yet. But then again, knowledge is power and I could certainly use it one day.
Cheers and Many thanks!
Thanks a lot for all the great infos. Very much appreciated.
I wasn't wrong when I made the decision to join this forum - even though I do not own a Bimmer - yet. But then again, knowledge is power and I could certainly use it one day.
Cheers and Many thanks!
