Did you change your expansion tank cap?

[PABLO]

hey guys, i was reading the 7 series forum and i found that the original expansion tank cap didnt release the over pressure. Does this happens with the 5 series? Did you change it? Should I?

Click here (http://www.homeofsbc.com/Hints/Replace_The_Expansion_Cap/replace_the_expansion_cap.html)

[Dan in NZ]

I had mine changed about a month ago. Despite the dealer assuring me that if it needed to be changed it would have been done by now, and having it in there for repairs all the time, they still hadn't picked it up. I got the service manager to check the original recall notice, and mine was on the list. It wouldn't hurt to take your VIN number into the dealer and get them to check if it needs replacement, it doesn't cost anything. The new caps are flat across the top, wheras the old ones had a bump.

[Bill R.]

notice about it or the previous owner. Yes you should change the cap if it doesn't have it already. Its not that it failed to release the pressure, its that it wouldn't release the excess quick enough and the worry was that the potential to blow out the connections at the heater core could cause someone to get scalded...








hey guys, i was reading the 7 series forum and i found that the original expansion tank cap didnt release the over pressure. Does this happens with the 5 series? Did you change it? Should I?

Click here (http://www.homeofsbc.com/Hints/Replace_The_Expansion_Cap/replace_the_expansion_cap.html)

[PABLO]

why did you have to take your car every time to the mechanic, blowing hoses and leaks every where? Because this is my problem. The hoses are very tight so they blow. Did you change the cap for this reason? Was it useful? Shuld the hoses be so tight?
Thanks for your reply

[PABLO]

but is it normal to get excess pressure in the system? Beacuse my hoses are very very tight and this week i'm taking the car to the mechanic to take out the head... to see if its cracked or something because we think that compression is blowing air into the cooling systam

[Dan in NZ]

My car was in the shop for various other reasons, nothing to do with exces pressure in the cooling system. As far as I know there was only one radiator cap related incident, a woman in the states drove her car around while it was overheating until the pressure was so great her heater core exploded, burning her legs. If you always have excess pressure in the system I would guess there is something wrong with your head gasket, I think there are easier ways to find out than removing the head.

[632 Regal]

Pablo, My friend, this has been bothering your car/system for wuite a while. At first you werend straight about your questions intention but I grasped it. The hoses will be almost un-squezzeable except fot the almighty Big D to work em. If you are busting stuff you have a severe problem which could very well be a blown headgasket not completely uncommon to this engine. Good luck with your mechanic and I hope we helped you to understand some of the issues.