Your help NEEDED

[Triv]

Hi everyone

I'm a newbie to the forum but an oldie to BMW's. I really need your advice, I have been to look at a replacement BMW, a 520i (M50) 5 speed, the car is great, very clean and drives very well. My only concern was with the way the temparture guage was behaving.
On the test run the guage never rose above the 1/4 mark (just above the blue), on my 525i the guage goes to the halfway mark and stays there. The heater is the car blew very hot so I ruled out a stuck or slow thermostat.

When I returned I opened the bonnet/hood and checked the overall heat of the engine and it was remarkable cool following a 5 mile drive. I turned on the ignition and the guage jumped to the halfway mark, I started the engine and it dropped to the 1/4 mark again.

Is this a) air in the system or b) head gasket or c) a stuck thermostat
Should I just walk away and find a good one? Although this one is a very good deal. Am I right to be concerned that if the car has been run in this state for some time that head gasket problems due to hotspots, are just around the corner?
Your help and advice is very much appreciated.

Jamie

[632 Regal]

sounds like a stuck thermostat in the open position, shouldnt be anything to run away from as long as the engine drove fairly well during the test.

[Paul in NZ]

sometimes my ar does this(twice) and both times it has been the connection to the temp sender.Since i removed both and reconnected i have had no problems.I tend to agree with jeff tho esp regarding your comment that the car seemed cool

[Kalevera]

I'm going to agree with Paul on this one.

I can't see how the TSTATs on these cars can get stuck open...there's a big ass spring that prevents this. Mine got stuck closed..and it overheated...

Check the temp gauge sender/wiring?

best, whit

[632 Regal]

Lowell, I think it was Bill that said that BMW stats tend to break or stick in the open position. I have seen this on other cars but not one of these in particular...yet. Someone has to post a pic of one (ahem Triv)

[Rory535i]

Was an easy and cheap fix.

[liquidtiger720]

Lowell, I think it was Bill that said that BMW stats tend to break or stick in the open position. I have seen this on other cars but not one of these in particular...yet. Someone has to post a pic of one (ahem Triv)

Too bad I threw away my stuck open T-stat.