1997 z3/2.9L help needed replacing thermostat

[louge1]

I have a 1997 z3 with 2.9L engine and need help with instructions and pictures if available on how to replace my thermostat and thermostat housing. the space looks very tight and looks like it may require removal of the radiator and maybe cooling fan too to be able to get access with wrenches and hand to do the changeout. can some of you please advise if this is true. if it is true can you supply helpful info. on removing all this stuff ...looks like removal of the radiator should br easy but the plastic snaps on the top are not so intuitive on how to release them, what is the trick to doing this ? are there other snaps that are holding the radiator in and where are they? how many hoses and other connections must be disconnected from the radiator? Looks like a mess to deal with .

thanks

LJ

 

[JGM3E3632]

that car has a 2.8. You must take the fan off. From there four bolts hold the housing on. They are 10mm bolts and are a pain to take off. But with patients the job is very easy. You should order an aluminum housing from AA tuning.com, it is a cheap and great insurance. Those plastic ones like to fail. While you are changing the thermostat you should drain the radiator and the engine block. The radiator drain plug is at the bottom on the left of the radiator. The engine block drain (I think it is a 19mm) is on the passenger side of the engine. The engine block drain is right above the #2 pre-cat oxygen sensor.

 

[louge1]

Jared, thanks for the prompt reply and suggestions ...Any helpful tips on how to remove the cooling fan blade? I see four 10mm bolts in the center of the fan are they the ones to remove for taking the fan off? the fan appears to be on a clutch and its just spins freely by hand.

what do I need to do to hold the fan center still why I back the bolts out? My understanding is they are rotated clockwise for removal. Or is there another bolt or bolts for fan removal.

Looks pretty darn cramp in there to get a socket wrench in to take the fan blade bolts loose as well! this will certainly be much better than trying to remove that radiator with all its connections.

thanks again for any and all help.

LJ

 

[Big Daddy]

Pelican Parts has lots of technical guides

Check them out for articles on DIY:
Pelican Parts

 

[louge1]

thanks Big Daddy great helpful site.....however it seemed a little lacking in instructions for the fan removal....the belt removal/replacement and thermostat/housting remvovt by with e/replacement was very good.

any further details on how the fan blade actually is removed will be good. looks like the belt is a must for thermostat and housing replacement or can I get those changed out with just the fan removed.

thanks again for such great tips on the site, etc.

LJ

 

[JGM3E3632]

no these four bolts are on the thermostat housing. Remember that the fan has left hand threads not right hand thread. You do not need to remove the belt.

 

[louge1]

thanks again Jared and Big Daddy for all the help. my brother and I managed to get the fan removed and changed out the thermostat and housting. reinstalled the fan and topped off the coolant reservoir to the cold full line. the replacement thermostat did not have an arrow on it like the original one so we installed in the same orientation as the old one was in when we removed it (not sure why its orientation is important). cranked the car and ran it around the block a few times with a/c on to get it to heat up and it did overheat again. initially ran the heater and it was still blowing cold air the whole time thte engine was warming up. never got hot air to blow out. then ran the a/c and the engine proceeded to reach max. hot temp. again...so now am at a loss as to my next step to resolve. even added more coolant as we relieveed the air via the bleed screw and tried again and still overheating.

is it most likely the pump is bad now or what? can i removed the thermostat and run safely without it installed ,,if so do I install the black O ring in the same spot where the thermostat originally went. \\???? If I run without the thermostat and it still is overheating then most likely I have a bad water pump now or not quite so obvious.


thanks again for both of you trying to help.

LJ

 

[JGM3E3632]

you must bleed the system with the engine cold and the car off. Unscrew the rad cap and the bleed screw. Fill the rad with coolant until it runs out the bleed screw. Continue to do this until all the air bubbles are gone.
[bmwdance]

 

[louge1]

thanks again Jared, ,,,so you think that is my only problem? still causing the engine to overheat and the heater to still not provide hot air? will give your suggestion a try tomorrow.

apparently you don't believe my water pump is faulty...or that I have installed the thermostat improperly---hard to understand that the thermostat would need to be oriented any particular direction.

thanks again for the continuing tips.

LJ

 

[JGM3E3632]

I never said that, how many miles are on the water pump? Those plastic water pumps like to go out after 60,000. miles. Replace it with one that has a metal impeller.

 

[louge1]

It worked Jared. we followed your instructions on bleeding air from cooling system tonite. worked like a charm All of a sudden the heater suddenly put out hot air.....we took the z3 out for a spin to warm it up further and it stayed rock solid on midway temp.

even got it back in the garage and turned on a/c to load the engine down more and it stayed at mid point temp. Looks like it was simply air trapped in the system preventing the coolant from being pumped effectively thru the system.

THANKS again to you and Big Daddy for all the helpful tips for resolving this problem for us.

Happy Motoring to everyone. You all have made some new fans of this forum vs. other auto forums with no help at all.

LJ

 

[JGM3E3632]

I'm glad we were able to help you. Anytime Man