e39 m5 thermostat?

[irish boy]

anyone ever have any problems with this? my car has recently has started only heating up to the first dot....then coming on up to half way in traffic only to fall again on the road!

rang bmw....they told me it definately needed a water pump despite my arguments. so, despite the full bmw history, i've left it into my local specialist for a stat. i've heard its a bigish job so not looking forward tothe bill just after christmas!

[rassi]

Not a huge job, think I paid €100 at a BMW dealer. The thermostat should open at 79 degrees C, you can check this in Test 7 in the "secret menu" - have a look here:

http://kinmak.com/?page_id=14

[mikey-r]

Just had my thermostat replaced. Exactly the same symptoms as you describe. My Indy did it for around £250 all in. I phoned two local dealers for prices and they both came in at just over £400.

[irish boy]

i was going to leave it but apparently it causes rich running which long term can harm fuel economy and power!

[mikey-r]

irish boy said:

i was going to leave it but apparently it causes rich running which long term can harm fuel economy and power!

I think, if you don't get it done, you also run the risk of carbon build up.

I did notice the fuel economy come back straight away... it is now "concerning" as opposed to "horrific"

[Neil.D]

Changing the Tstat is not a hard job, its just hard to get it right. It is very fiddly and you run the risk of a fairly decent coolant leak if its wrong. I did and had a fairly grotty time trying to rectify it. Eventally I got a garage to sort it all out. Ended up having a busted weater pump too which didnt help.
Bravo for taking it to a garage, got to be the best idea.

Why have they diagnosed the water pump out of interest?

[irish boy]

lol without seeing the car they said it was a water pump because they 'always' go.

bear in mind this is the same main dealer who said i needed a power steering pump. i got a specialist to check it out and a J clip had slipped iff one of the hoses....20p to fix and no charge. i think i actually despise them, but my car had a full service history from them when i got it and i said i was going to keep it up. not so sure now tho.

[AC Motors]

irish boy said:

lol without seeing the car they said it was a water pump because they 'always' go.

bear in mind this is the same main dealer who said i needed a power steering pump. i got a specialist to check it out and a J clip had slipped iff one of the hoses....20p to fix and no charge. i think i actually despise them, but my car had a full service history from them when i got it and i said i was going to keep it up. not so sure now tho.

Time to try elsewhere methinks ! Check out the indy's listed on the BMW car club website for any in your area.

[Neil.D]

Waterpumps dont always go. The weep from the bearings before they acually fail. If you just have a low tempreture then its the Tstat - very common. If you have a coolant leak then you could be inclined to believe the garage. If its not losing coolant then its just a common mechanical Tstat issue.

[broster]

rassi said:

Not a huge job, think I paid €100 at a BMW dealer. The thermostat should open at 79 degrees C, you can check this in Test 7 in the "secret menu" - have a look here:

http://kinmak.com/?page_id=14

genuine price on the stat is around £70-80

it of a fiddle to do, did mine and economy have improved by 2mpg.