Coolant Expansion Tank
 

Can someone give me the idiots guide to replacing the expansion tank? Just received a quote from indy dealer for $371 to replace the tank - a tank that can purchased for less than $80. I like to tackle as many of the projects on the X5 that I can within reason. Any tricks or special tools required?

Thanks

no tricks or special tools beyond a (IIRC) 13mm socket and flat-tip screwdriver.

basically, disconnect the attached hoses and pull the 2 mounting nuts, pull the box up and disconnect the temp sensor (twist and pull down), pull off the cap, toss the old one, and reinstall new one in reverse, then fill back up with 50/50 antifreeze and distilled water, and you're done.

Took care of mine not too long ago after the old one developed a crack down the corner, including time to lug tools and cycle coolant into the system, was done in about a half hour :)

E

Thanks. Looks like I've got a project for this weekend.

Search the forums there are some good threads. I would order the hard plastic tubing that circles the top of the tank, and a new bleeder screw, and a new filler cap as well. What I found is when you pull the hose off the plastic tubing, because it gets brittle over time it can break very easily. Also make sure you have about a quart of antifreeze on hand cuz you will spill about that much. When you remove the hoses have something to catch what little fluid comes out of them to save wiping it up later or risk your pet dog or cat getting into it. If you break the plastic tubing you will be dead in the water until that part comes in so spend the $12 bucks or what ever it costs before hand.

Once you replace the tank and fill it, start the car and idle it with the heater on high and the cap off the tank. Once the bleeder hose starts pissing back into the tank it will be correctly pressurized and you can put the cap on and you are done. There is a thread that shows the correct part numbers mentioned above. No special tools required.

So long as your fill cap is not damaged, I wouldn't bother ordering a new one (According to realoem, it's a charge + core), and the expansion tank I receieved had a new bleeder screw attached already.

YMMV, though

Erik

Recently at the dealer, I paid the $371, which included the $105 diagnosis fee. I was about ready to do this myself somehow (post evaluation) when they also noted the OSV issue and suggested that it be replaced. I produced a copy of the original service order (Feb. 2010) and they, under BMW Warranty (2 yr/Unlimited miles), replaced it no charge. That "saved" me around $900 or so. While I typically don't like to go to dealer as I question their labor hours per project. It was nice to know that that warranty is as good as it is and is transferable for cases like mine. Good luck. BTW, I got check coolant levels often about the tank. The service adviser was also upset to hear that I replaced the lost coolant with 50/50 Pre-diluted Prestone. It did fine and I am not sure why he was really upset. Homeboys still charged me $25 for BMW Coolant on this incident.