Good stuff. I have 73k on my 2001 530i and am preparing a trip to the American Southwest (can ya say, HOT?!) at the end of July. Just had a pressure check done to the whole system and nary a leak to be found but everything is still original.

My BMW mechanic told me the expansion tanks are the ones to explode on a whim on the I6s whereas the radiator main upper necks go on the V8s.

A buddy and I replaced the belts (also original) without removing the fan. It goes fast with two guys but one guy, it is probably easier to remove the fan/shroud.

 

Nice write up cn"n"90.

 

I am doing the fan clutch on my E39 this weekend. Just to be clear the fan clutch is the # 2 picture in this diagram they call a FAN COUPLING, right? http://www.realoem.com/bmw/showparts.do?model=DE53&mospid=47588&btnr=11_1534&hg=11&fg=35

Also my fan looks to be in good to perfect condition at 63K should I be replacing it as well or anything else?

/Everything in the cooling looks fine.
//Just replacing the fan clutch as a precautionary measure.

 

CN90 Great info replaced the water pump yesterday, was a great help. Thanks

 

The guide has been a great help in getting my hoses, fan clutch, and waterpump upgraded.

However, I am at unable to get the water pump out due to a metal pipe that extends from the right of the block all the way across to the left of the block and right in front of the waterpump. I was able to get the thermostat housing out, but I can't find any way to get the waterpump out, even with the air intake parts removed and after trying for 2 hours; theres just not enough space with the metal pipe in the way. I haven't been able to find any reference to this pipe anywhere. Any ideas?

Edit: For anyone else with this problem, I guess the metal pipe needs to be removed. From this diagram (#11), it can be removed as it seems to be just an air line:
http://www.realoem.com/bmw/showparts.do?model=DN62&mospid=47548&btnr=11_2285&hg=11&fg=50

 

The guide has been a great help in getting my hoses, fan clutch, and waterpump upgraded.

However, I am at unable to get the water pump out due to a metal pipe that extends from the right of the block all the way across to the left of the block and right in front of the waterpump. I was able to get the thermostat housing out, but I can't find any way to get the waterpump out, even with the air intake parts removed and after trying for 2 hours; theres just not enough space with the metal pipe in the way. I haven't been able to find any reference to this pipe anywhere. Any ideas?

Edit: For anyone else with this problem, I guess the metal pipe needs to be removed. From this diagram (#11), it can be removed as it seems to be just an air line:
http://www.realoem.com/bmw/showparts.do?model=DN62&mospid=47548&btnr=11_2285&hg=11&fg=50

Yes, that bar has to come out. Held in place (it I recall correctly) by two screws/bolts on each side. There is an o-ring on each tip of that bar - make sure you don't damage/break it.

Will

 

UPDATE:
1. Stay away from MTC Fan Blade, it cracked after one year. Use only Dealer Fan Blade.

2. The WP Pulley is made from hardened plastic (it is not metal) and should be changed around 140-160K to prevent cracking and left starnded.

3. During re-install, it is a pain to start the first few threads of the Fan Clutch. Here is my trick using the cord:
http://www.bimmerfest.com/forums/showthread.php?t=240143&

 

that is cute way to get it on but with new W/P thread, I just hand put clutch on and turn the fan counter_clock wise few times then, start the car. It is tighten by itself. I did mess up old W/P thread by using 32mm wrench, learn the hard lesson.

-John

 

4. Water pump pulley bolts are low torque. Use some locktite and hand tighten.

5. Sensor in lower hose tends to leak from oring if you install it on a new hose. If it has been a few years, save yourself the trouble and just buy a whole new sensor with oring, as the oring is not sold separately. It's $39 at the dealer or $22-$25 online.

 

All dealers in Boston ares charge $45.99 for the low hose with sensor.

 

my 535i v8 was mysteriously leaking water. the first pressure test could not found the leak. then went to another mechincal to do the test still could not find where wasleaking . as it leaks about 1/5 amount of coolent of the expension tank. then send the car for test when it iwas hot. and found out there was a tiny leak from the water pump. the car has done 150,000km ( about 90,000 miles). ge tthe pump replaced. no more problem.

 

today, my two serpentine belts, expansion tank clip and my fan clutch arrived. i am waiting for my water pump to arrive on tuesday. i will be a grease monkey next weekend.

some of the DIY write ups in here are so billiant that repair manuals are now absolete.

you guys rock!!! thank you!!!

 

today, my two serpentine belts, expansion tank clip and my fan clutch arrived. i am waiting for my water pump to arrive on tuesday. i will be a grease monkey next weekend.

some of the DIY write ups in here are so billiant that repair manuals are now absolete.

you guys rock!!! thank you!!!

Its pretty easy. Getting the fan clutch off for me was the hard part, it took me about 4 hours of screaming. My belt had shreded when my water pump seized so I couldnt hold the pully in place with a piece of wood wedged into the serpentine shafts.

That is byfar the only tough part. The rest is like playing with legos.

 

2002 540i Water Pump replacement

I totally agree, I just changed my Water Pump, hoses and belts on my 2002 540i, and although nothing adressed my specific year/model, the links on this forum (and some others as well) were an incredible help in preparing for the work in advance of the parts arriving (big thanks to cn90 for the groundwork and writeups!) The ideas really translated for me, also Mike for key tips! Basically did a $700 dealer job for $160 in parts! Bled the air a few times and 2 days later, drove the car from Florida to New York without a drip, the needle didnt budge (of course I was running the computer test program #7 for an exact temperature readout...110 degrees celsius the whole 1000 miles! If anyone needs any tips on the procedure feel free to post and I will respond[ (PS went with the Graf metal impeller)

 

I totally agree, I just changed my Water Pump, hoses and belts on my 2002 540i, and although nothing adressed my specific year/model, the links on this forum (and some others as well) were an incredible help in preparing for the work in advance of the parts arriving (big thanks to cn90 for the groundwork and writeups!) The ideas really translated for me, also Mike for key tips! Basically did a $700 dealer job for $160 in parts! Bled the air a few times and 2 days later, drove the car from Florida to New York without a drip, the needle didnt budge (of course I was running the computer test program #7 for an exact temperature readout...110 degrees celsius the whole 1000 miles! If anyone needs any tips on the procedure feel free to post and I will respond[ (PS went with the Graf metal impeller)

Does any one have detailed instruction (possibly with pictures) to remove the water pump from V8 540i? I have removed most of the "stuff" (belts, fan, shroud, etc) and just need more details on removing and installing new water pump. Thanks.

 

How to tell if you have Mechanical or Hydraulic Tensioners
I found out an easy way to tell if your car has mechanical or hydraulic tensioners. My car has mechanical tensioners/rollers and they have Torx T47 heads on the rollers, as opposed to the hydraulic versions that have allen heads on them. Unfortunately, with the mechanical tensioners, you can't replace JUST the roller, like you can with the hydro versions.

 

I just pulled my fan off tonight after ages removing the shredded belt wrapped around both crank pulley and the infamous 32mm nut.

Anyway this is kinda embarrassing to admit because I'm not a butcher by trade but surprising enough that I have to share it - I managed to undo the 32mm nut using the slip-joint pliers in the factory tool kit (I know, I know... but around the right way and adjusted right they fit fantastically with heaps of leverage, no damage at all) while wedging the remains of the old serpentine belt between crank and waterpump pullies with the grooves engaged on both using a flat bladed screwdriver up the middle and a bit of shoving to lock it up.

In hindsight the belt trick probably only works if your water pump is so devestated that side-loading locks it but you never know it may work for someone else so maybe give it a go if everything else has failed.

Talk about lucky, I'd just returned from a 720km weekend away, drove to the supermarket for food, parked the car, and the steering went heavy as the belt finally got tossed off just as I was about to turn the engine off

Thanks for all the info guys, great forum!

Geoff.

 

How do you keep the water pump from turning when you are turning the 32mm nut?

 

Hi, I turned the serpentine belt inside-out and forced it between the crank pulley and the waterpump pulley with the grooves properly engaged on both pullies, pushing very hard on a very large flat bladed screwdriver between them from the power steering reservoir side (passenger side on my RHD car here in New Zealand) to lock the two pullies together while tugging on the crude tool to shock the nut into moving.

BUT it may be that it only worked for me because my shattered pump (with at least six roller bearings completely spat out!) tended to lock up with side-loading.

The nut wasn't very tight though, so the belt trick MAY work on a healthy one... can't hurt to try I guess

All the best!!
Geoff.

 

Radiator air bleed?

Reading all this I can see I am going to need to do a complete cooling overhaul.

I have a 2000 540i

I had a lead from the bottom of the expansion tank and a low level coolant message. I change the tank and sensor on the bottom. The tank has lots of broken parts inside and the sensor was melted and leaking.

All seemed well with the test drive but then after only 1.5 miles yesterday the temp needle pegs. I turn around and the needle returns to 12oclock and slowly creeps up. When I stop the engine is still relatively cool.

I am not sure I bled air properly. Could this be causing the issue? It did not seem like I replaced enough radiator fluid.

Thanks,
Mitch

 

I have to change the radiator on my year 2000 e39 530i sport, its an Automatic. Does anyone know if I HAVE to undo the transmission fluid cooler hoses from the transmission oil cooler to give more access to remove the radiator, or can I just remove the radiator leaving all the transmission pipes etc alone????

Thanks

Jez

 

rad failure at 71.5k mi - '01 540i

Looks like I'll be joining the club. My '01 540i with 71,500mi has been giving me an occasional low-coolant warnings for a few weeks now. Every time I checked the level in the expansion tank, the indicator has been bobbing up - so I figured the sensor was bad. When I looked at it closer this weekend, I noticed a small hairline fracture near the radiator upper hose neck. It's been slowly leaking out fluid! So my theory now is that I'm probably borderline low on coolant, as the warning message only goes off once after 1 min of driving, and then goes off, as the coolant volume increases.

I'm ordering parts soon, and going to replace the rad, expansion tank, and all the hoses. I'm probably gonna wait with the water pump and the belts, and replace them at next years coolant change.

--Rob

'01 540i
'07 X3

 

Looks like I'll be joining the club. My '01 540i with 71,500mi has been giving me an occasional low-coolant warnings for a few weeks now. Every time I checked the level in the expansion tank, the indicator has been bobbing up - so I figured the sensor was bad. When I looked at it closer this weekend, I noticed a small hairline fracture near the radiator upper hose neck. It's been slowly leaking out fluid! So my theory now is that I'm probably borderline low on coolant, as the warning message only goes off once after 1 min of driving, and then goes off, as the coolant volume increases.

I'm ordering parts soon, and going to replace the rad, expansion tank, and all the hoses. I'm probably gonna wait with the water pump and the belts, and replace them at next years coolant change.

--Rob

'01 540i
'07 X3

FWIW...
Do EVERYTHING! My water pump self distructed at 100k - no idea if it was original or not as I've only had the car since 89k. There was absolutely no warning whatsoever. I'd never put even a drop of water into the car since i got it, no need. But a shudder was felt on the x-way and immediately the red light came on for no charging so I figured I lost the serpentine belt. When I pulled over and looked the belt was wrapped around everything and the fan was totally wobbling around but still (luckily) attached to the pump shaft. The bearings were scattered everywhere from it though.

I then tried to just replace the pump but one thing after another has lead me to replace everything. Just do it once!

A big tip... get that emissions pipe off - you can get the pump in there but its just too difficult to line it up correctly as you've other pipes it needs to fit on in addition to lining up the bolt holes.

 

i have a e39 528i with an inline 6 and was wondering how to bleed the cooling system i am new to the BMW world of DIY mechanics i can do most of the work with just a little instruction and help i am changing the water pump and thermostat also so any info and pics would be a great help and appreciation :thumbup:

 

Another bit the dust...

I've been trying to track down a clunking noise at low rpm's, suspecting the water pump for a while. Yesterday it got really bad, so on the way home I stopped at the dealer and got a new water pump, belt, pulley, etc... (I just replaced the fan clutch and blades last october when I replaced the alternator, so I figured they're still good). After I left the dealer, I was getting onto the freeway when I noticed my temp sensor going up fast. I pulled off to the shoulder, popped the hood and saw that I had shredded my pump had seized, shredding the belt and wrapping it around the clutch. The bearings had separated and I could see rust and corrossion around the balls Anyway... towed it home and am currently enjoying a post pump beer. Thanks for all the hints and help, guys!

 

FYI, this might be unique on my car (cuz it isn't confirmed on RealOEM) but... those of you asking how to take the 32mm fan clutch nut off: The pulley uses two sizes of bolts to hold it on, one set is short and black, the other is gold and long. Gold @ 12 & 6, black @ 3 & 9. You can loosen the gold bolts to give you a place to use a universal fan clutch wrench (rented one at Checker for a $50 deposit, free on return). If I had been thinking, I'd have taken pictures. Beats the hell out of beating the hell out of your fan clutch nut / wp bearings with a sledge and static friction.

 

Cost of cooling system overhaul

Guys, anyone have an idea of what a fair price for cn90s cooling overhaul on a 2003 530i at a bmw mechanic (non dealer)? I'm trying to get an idea of how much extra I need to pay to guarantee I don't screw up my car trying it myself!

 

Probably $600-$800 for complete cooling system,

 

You sure? I would also like to know, was quoted $2k for the job by an indy. This included

Water pump
Radiatior/overflow
Thermostat/sensor
Belt
Three pulleys for belt
All hoses
Fluid

Anyone else?

Thanks

 

Flat5, What did you do to fix your coolling system? I did not see more posting on this. I am in similar situation with my 2002 525i. Pondering how to fix cheap, but sure not to mix up.
Thanks,