fitting a new water pump??

[kwoffa]

I want to fit a new water pump (s50) has anyone done it ? is there an idiots guide to do this? have searched but cant find any source of info? roughly how long to do? special tools? bleeding the system afterwards? any help will be good ! thanks in advance. Mel

[c_w]

I haven't changed the water pump on my car but I have changed the thermostat, which compared to other BMW straight 6s (eg 2.8/3.0) is a bit more of a lengthy job (waterpump on the 2.8 is really easy). Most annoying bit for me is removing the viscous fan! (can be a pain! Hammer and long chisel seems to work best for me).

This link might be of help to you;
http://www.realoem.com/bmw/showparts.do?model=CM92&mospid=48075&btnr=11_1321&hg=11&fg=35

If you're changing the water pump I imagine you're going to flush and refil the cooling system? If so remove the lower undertray and on the back of the block (exhaust side) there is a drain plug on the side, 13mm or so I think). Leave this out and you can do a full flush using a hose pipe into the block where the water pump goes (also flush through the radiator top hoses etc).

I remember undoing the end throttle sensor to access the bolts for the top of the thermostat. The top housing is bolted to the top of the pump but has a short alloy pipe merely pressed into it with a rubber o-ring on either end. I bought new O-rings for these bits.

For refilling and bleeding, I fill up the expansion tank and run the engine with the cap off until it's up to temperate, topping up as it drops down. This always seems to work for me.

[kwoffa]

As ever ..thanks Chris..roughly how long would you say this should take? and is the cowling around the fan etc..a pain to do..a garage has told me 4 hours! and they suposedsly know what they are doing,i dont mind the length of time but as i dont have a garage and am going to be reliant on the weather its good to know roughly how long..is it worth me getting a haynes?ime no mechanic but i really dont mind doing this myself...havnt done anything like this for years ..

[c_w]

I can't remember now if you can remove the fan without touching the surround that is clipped to the radiator; if you have to remove the surround it does all lift out (with the fan loose lifted out with it).

I think it'll be one of those jobs where you can see what needs to be done when you get to do it; refitting being probably 4x quicker than disassembly! 4hrs sounds about right though if you done quickly, but I find these kind of jobs always take long er than anticipated! Getting the car in the air, flushing it out etc.

[Wav]

This tool and a 32mm spanner should help you remove the viscous fan pretty easily. Remember it is a left hand thread.

http://www.tooled-up.com/Product.asp?PID=28861

Paul

[kwoffa]

Cheers Paul...
Have you done this job youself?

[Wav]

I haven't done the water pump no, but I have removed the fan and radiator assembly in order to remove the engine. I think if you drain the radiator and remove it you'll have a lot more room to work. 4hrs sounds about right as you'll have to remove a lot of the intake assembly too.

Good luck,

Paul

[c_w]

This tool and a 32mm spanner should help you remove the viscous fan pretty easily. Remember it is a left hand thread.

http://www.tooled-up.com/Product.asp?PID=28861

Paul

Yes that tool would probably save lot of cursing as the fan spins round trying to undo it :D

[kwoffa]

Ok Chaps gonna bite the bullet ! and do this so far i need new water coolant/tool to hold fan still while undoing nut..spanner for nut...if when undoing the fan and removing cowling etc is there enough room to get at the pump as after looking at where the pump is etc..i think its better to remove the radiator so as not to damage it and allow better access..my belts have been changed not so long ago..the thermostat has been renewed too..is there anything else that i will need..and any information regarding removing radiator would be usefull ..thx in advance.mel

[Wav]

I would definitely recommend removing the rad for extra access. Once the cowlings and fan are off and the two top latches are free the radiator should lift out (assuming you've disconnected the coolant and breather pipes first).

Good luck,

Paul

[kwoffa]

Thanks Paul..so am i right in thinking..remove hoses etc and then its just the two top latches that hold the rad in...is that all ? i know the cowling justs puuls off !

[DonKijote07]

you dont have to remove hoses, just unclamp them, drain fluid, take rad out, and the fan will be a pita. After that its straight forward. I would say replace thermostat while you're at it and any hoses if needed. make sure you tighten everything to specs, double check your fan after you put it back on and also start the car and see that its right. don't forget your lubricant!

(im not an mc owner yet, but worked on cars, if i missed anything specific to this engine lmk. I am here to learn after all)

[c_w]

Radiator hoses (top and bottom) are pretty cheap from BMW - when I changed my thermostat/coolant I replalced the hoses too;

Bottom radiator hose 11531401726 £14.90+vat
Top radiator hose 11531317394 £15.49+vat

[kwoffa]

After undoing the top latches of the radiator unclipping the shroud,undoing the two most vissible hoses i still cant get the rad to come cleanly out ! its not catching on the loose hoses but appears to be caught in the lower right hand corner looking from the front..???

[kwoffa]

??........

[Wav]

Is the breather hose still connected on the top right hand side? Otherwise it could be something catching on the oil cooler underneath?

Paul

[kwoffa]

undone all hoses...was running out of time,just couldnt work it out...

[speed8]

Did you get sorted on this.... I can tell you what you'll be catching up on because I just changed my rad today.

The oil cooler is mounted to the bottom of the rad. The pipes for it are on the right and probably what is holding you from pulling it out. There is a bolt on the left hand side bottom of rad (looking from front) that you need to undo so you can pull the oil cooler out of it's mount. You need to take off the front undertray to get to it.

Once you've done this the rad should pull out easily.

[kwoffa]

I ran out of time with this job and called in a mechanic mate of mine..and he did it for me..the pump replacement wasnt as easy as it sounded ! however he did not need to remove the radiator,but at least i feel more confident that nothing is gonna brake now,thanks for all the imput chaps,much apreciated.Mel