This is my first attempt at writing a DIY but i couldnt find any DIY involving the thermostat on the m62.
This was done on a 1998 540i/6 i think they changed the cooling system a little in 99, but im not sure.
This is a very easy job and you dont have to remove the fan clutch.
11531437526 - Thermostat (includes housing and O-ring) - $90 at my local dealer
1 Gal of your favorite antifreeze
Phillips head screwdriver
Flat head screw driver
2" 3/8" ratchet extention
3/8" socket u-joint
CRC MAF cleaner (optional)
1. jack up the front end.
2. remove the splash guard by undoing the 9 1/4 turn phillips screws
3. remove the radiator drain plug and drain about 1 gallon of coolant then replace plug
4.loosen 2 hose clamps and undo the 2 clips holding the Maf housing and intake tube.Disconnect Maf harness by twisting it.
5. disconnect ICV elbow at intake tube.
6. pull out Maf and intake tube (while you have the MAF removed you should consider picking up some CRC MAF cleaner and spraying it down)
7. remove 10mm bolt holding in inake resonator then remove it.
8. loosen hose clamp holding lower radiator hose to thermostat then move it out of the way (put papertowels under the thermostat to catch cool ant)
9. remove harness on thermostat then remove 4 10mm bolts holding thermostat to water pump.
10. pull out thermostat, some more coolant will pour out so be ready (I had to knock it loose with a screw driver)
11. Put in new thermostat and reverse and repeat.
12. refill radiator and bleed.
Real nice writeup. Just had a question....How did you bleed the system?
Thanks for sharing.
2003 E39 M5 www.mym5.net
Sold: 1997 E39 540
Sold: 2004 E60 525
thank you! I will be doing mine soon and this certainly will help.
Ive herd a bunch of different ways to blead the system. the two i can remember is putting heat at full and fan at min opening the bleeder screw and the cap and slowly fill till its at max and doesnt go back down
another is to slowly open the bleeder screw while the engine is hot and close it when a steady stream of coolant comes out without bubbles. just be careful beacause the coolant will be hot
it couldnt hurt to do both.
make sure to check the level the next few days and top off if needed.
Sorry to bump an old thread, but I'd rather bump a related thread than start a new one.
I'm replacing the water pump on my '97 540i tomorrow and am thinking I should replace the thermostat as well. From talking to the BMW dealer it seems like the thermostat is only sold with a new thermostat housing on the 540. What is the reason for this? Seems to make more sense to re-use the old housing and just buy a new thermostat to put in (IE much cheaper!). I know I didn't have to replace the housing when I did the thermostat replacement on my 528 so I'm wondering what the reason is for having them sold as one for the 540?
Bottom line is, should I buck up and spend $100 on a thermostat that comes with the replacement housing or would re-using the old and just dropping in a new thermostat from the autoparts store work just as well?
I just got the entire new unit from bavauto for like $75ish? I figure since its plastic it may break when you swap out the parts or down the road.. id just replace it and know its taken care of.
Just dont get the aftermarket aluminum housing, they leak!
Great write up! I replaced the thermostat and my engine temp is still running 1 tick passed operating temp. I followed both ways to bleeding the system. I add coolant as needed. But it still runs hot. Can anyone help me trouble shoot this? Help! Thanks in advance!!
As for the question near the end about replacing just a thermostat without the housing, I faced the same question when replacing my thermostat on an e39/m54 engine. Bottom line is that the theremostat is integral to the housing on some of the newer engines (also there is an electric sensor), so you can't keep the old housing and just change out the thermostat. I got the best price at autopartswarehouse.
Not sure if this is relevant to every car but I looked up the whole water pump and thermostat change. this directed me to this link http://www.bimmerboard.com/forums/posts/199986 On this link they talk about drilling a 1/16" hole in to the thermostat itself to relief air pressure. Does that sound correct? Has anybody done this before? Would this not affect the thermostat function?
This is a really old thread but since I'm doing my own search i figured id answer that last question incase someone else came across this post and was wondering the same question.
OEM thermostats do come with a whole on the thermostat. It serves 2 purpose's #1 directional: the bleed whole must be positioned in the direction facing upward. #2 it allows a small amount of coolant to be transferred when thermostat is in closed position.
If the thermostat dose not have a vent whole @ the top it is not an oem product & will be opening & closing a lot more which may bring the thermostat live span down.
image links are broken...do someone have the images????