DIY: Stewart Water Pump + Expansion Tank + Coolant Change + 2 Tensioner Pullies

I have no blue Drain Plugs on my 01 330i ... any ideas on where they might be?

doing this tomorrow

Alright, I just finished a complete coolant system overhaul and went for a test drive, but it's still overheating!

I'm guessing there's only two things that it could be: 1) there is air trapped somewhere or 2) the radiator itself is clogged.

So first off, can someone give me a detailed set of instructions on the best way to bleed the radiator?

sticky this, great write up

nice write up...this is what I was looking for..

Originally Posted by jpainter187

Alright, I just finished a complete coolant system overhaul and went for a test drive, but it's still overheating!

I'm guessing there's only two things that it could be: 1) there is air trapped somewhere or 2) the radiator itself is clogged.

So first off, can someone give me a detailed set of instructions on the best way to bleed the radiator?

Check the PDF links at the end of the DIY (1st page) for proper bleeding. They are official instructions from BMW and I never had a problem.

Originally Posted by Bimmer330cibro

sticky this, great write up

Originally Posted by xxenycejattxx

nice write up...this is what I was looking for..

Thanks!!

I will using this soon I think.

My expansion tank has crusties along the upper seal.

Originally Posted by paraklas

And in case somebody is wondering what sound a faulty wp does, here it is (notice the hishhhhh hishhhhh hishhhhh):

Very helpful for future reference! Thanks!

So in the last month I've replaced all the belts, all the pulleys (converted to hydraulic) and now replacing the expansion tank on my 2001 330i auto. Got my parts from koperformance (highly recommended) and tackled yesterday.
Was stressing out on how difficult the tank removal was going to be, removal of the hoses and possible breaking of the auto thermostat so I ordered many extra parts.
Well after only 45 minutes I must say this was probably the easiest DIY I've done so far. Hoses came off with no struggle. I don't have a thermostat for the tank so that was not an issue. The tank itself...well damn came up in 30 secs! My 10 year old daughter could have pulled it up! Installation was super easy and it did not take much to put it back. Was skeptical that it was so easy to reattach that it would leak like crazy but not even a drop! Bleed easily and I'm all good!!! I keep my engine bay pretty clean and our mild climate in Northern California may make things easier.
Thanking all the forum members for all the good tips and sorry for those that had such a hard time.

Big thanks to everyone on the forums for the DIYs!

I just got done with replacing the oil filter housing gasket, the valve cover gasket, and overhauled the whole coolant system as well (and a few other pulleys here and there).

I only ran into one little problem...the coolant level sensor inserts easily into the my new expansion tank, however it won't turn 45 degrees to lock...I used quite a bit of force but stopped short of breaking it. Good news is there is no leak. Bad news, however, is I keep getting the "add coolant" light on/off as I drive.

Anyone had this problem? I'm thinking of just ordering a new coolant level sensor, but wanted to ask first...

Again, THANKS all!

I just changed my water pump with a Graf water pump. It has the metal impeller instead of the cheap plastic one on the OEM ones.

It only cost me $50 ish. Much cheaper than the pricey Stewart ones.

It uses the BMW remanufactured water pump number on it. I'm not sure if it was a remanufactured BMW water pump or a new water pump, but it had the a metal impeller.

My parts guy told me they are new. They had the wrong part number matched to it.

It works perfectly on my car.

Let me know if you want one. I can buy it with my account.

It's not a plastic impeller but rather a composite material. Unfortunately there are 3 parts that can go wrong in the BMW and other OE water pumps: impeller, bearing and seal. The Graf one with the metal impeller has 1 less thing to break although I've read a couple of posts where the metal impeller went into pieces when the spot welds broke. In that case, better to have composite material floating in the cooling system rather than metal bits. The stewart pump addresses all 3 issues with upgraded seal, bearing and of course impeller and as a plus you get the lifetime warranty & the claims of better flow and higher efficiency. If it's a remanufactured unit it probably uses the OEM housing with a new bearing, seal & impeller.

Just did this today as my car overheated thismorning and I was preparing to do it anyway. (overheated due to coolant leak I believe, coming from thermostat area)

noodlesan Big thanks to everyone on the forums for the DIYs!

I only ran into one little problem...the coolant level sensor inserts easily into the my new expansion tank, however it won't turn 45 degrees to lock...I used quite a bit of force but stopped short of breaking it. Good news is there is no leak. Bad news, however, is I keep getting the "add coolant" light on/off as I drive.

Anyone had this problem? I'm thinking of just ordering a new coolant level sensor, but wanted to ask first...

Again, THANKS all!

Same thing happened to me, although I tested it outside the car, when trying to turn it I noticed the expansion tank slot that the sensor turns in was poorly made and stoping it, got a little knife and carved it away and presto it turned. Would be alot trickyer on the car,
good luck

Also I ran into a bleeding problem, I poured and poured with engine off and heater on, stopped when it stayed full (bleed screw open)
Turn on car and for a minute inspected but no more coolant was needed and nothing was coming out of the bleeder screw, I drove to my mechanics thats 2 minutes away so he could do it plus make sure there wasnt some leak somewhere (pressure test the system)
Got there he was sadly closing, but said that you were supposed to use a vacuum thingy (he didnt say thingy offcourse ) and I had an air lock in my heater valve as no hot air was coming out yet. so when I got home, undid bleed screw and alot of air/steam came out.

So I guess ill try again, this time do i leave bleed screw open until up to operating temps?

Cheers

now thats a damn write up. that was excellent.

excellent write up, sorry to hit up and older topic but its very useful...

Man this is a sick writeup!

My waterpump went off today. Its going in for replacement tomorrow.

Well done for the writeup!

this is a great thread but do you really have to quote the whole post with all the pictures?

sweet DIY Cyprus!
How is that Stewart Pump holding up 2 years later?

Originally Posted by delmarco

sweet DIY Cyprus!
How is that Stewart Pump holding up 2 years later?

It's like it was installed yesterday. Spins very smooth (did the belts 2 days ago and spin it by hand), no leaks, coolant temp is between 75-85 degrees Celsius, no odd noises and the threads that the mech. fan screws to (for autos) are still rust-free.

Same goes for the ESS pulleys, they outlasted the OEM ones two times
Can't say the same for the contitech belt, after 20000miles it was cracked as hell so I'll shorten the change interval; every 2nd oil change.