M54 oil filter housing gasket replacement - water pump replacement opportunity?

[JSz4]

After my first track day in the Z4 I noticed some oil dripping from the bottom of the engine but couldn't see where it was coming from so took it to a garage who got said they could see when running the engine a small seeping from the oil filter housing gasket. The garage said the gasket is pretty cheap but it will be several hours labour to fit as it'll involve removing parts that bolt to the housing, such as the alternator, as well as removing the belts etc.

Since the belts are coming off is it sensible to replace the water pump at this point and how much are they normally? It's a 3.0i so M54 and 118k miles, I've owned it 6 years since 86k miles and haven't replaced it in this time.

Thanks for any advice, Jeremy

 

[bigwinn]

I’ve got that down to an hour now- fairly simple once you’ve got the alternator off

Water pump doesn’t get touched but it may be worth doing while the belts are off

 

[caius]

If you're replacing the water pump and therefore draining at least some of the cooling fluids, I'd take the opportunity to replace the Thermostat/housing and possibly the expansion tank as well. Both are known weak(er) points in the system prone to cracking or leaking. I've just done all of them recently as the thermostat was foobar (2.5i, 112k miles), cost me about £130 in parts (Febi/Meyle).

 

[Chris_D]

Concur with above.
Took the opportunity to replace my thermostat, waterpump, oil filter housing gasket when replacing my CCV system as I had an over-coolling issue at the same time as the CCV failed.

Therefore, consider also replacing the CCV system if you don't know how old it is as it might be on the way out too.
If you do decide to replace it go for the cold-climate Febi one as it has thicker lagging which could prevent condensation buildup. It's a faff to get in place due to the lagging but a good preventive maintenance item.
Replace dipstick washer too.
And while you have things disassembled, inspect/replace DISA and definitely replace DISA gasket if it hasn't already been replaced.
Inspect/clean ICV too.

 

[JSz4]

Thanks a lot for the advice, I'd asked the garage for a price for the water pump, how much is this normally on it's own?

 

[patriot66]

Thanks a lot for the advice, I'd asked the garage for a price for the water pump, how much is this normally on it's own?

A Meyle waterpump with metal impeller and 2 year warranty can be had for less than £30. I fitted one 4 years ago and still going strong

 

[Gregory_tolson]

Just fyi, it takes like 5 seconds to remove the serpentine belt and AC condenser belt. They are simply removed from two different tensioners, much easier than some cars that require stretching the AC condenser belt on to the pulleys and having to cut them if removing. The water pump and thermostat are not affected when changing the oil filter housing gasket. Dont perform the cooling work solely from the fact the belts are off so might as well do the job. It literally takes like 5 seconds to remove them.

However, if you are willing to do any cooling work I highly recommend doing all water pump, thermostat, expansion tank, hoses, replace pulley, and CCV in one shot. You probably can get away with just water pump and thermostat alone but those hoses and expansion tank do eventually fail because they get insanely brittle. The mileage you are at it makes total sense to tackle the entire system since roughly between 100,000-150,000 miles its highly recommended to replace the entire system. I also recommended doing the CCV at the same time as the cooling refresh because there is one plastic cooling tube that runs underneath the intake manifold that should also be replaced with all the hoses since that tube eventually cracks. The pulley i also hear can crack if not replaced during the overhaul, which is why i recommended that. Some cooling kits come with hoses, pulley and expansion tanks all together. With the intake manifold off it makes replacing the CCV a simple, simplleeee job. The big cost is going to be the removal of the intake manifold.

 

[JSz4]

Just fyi, it takes like 5 seconds to remove the serpentine belt and AC condenser belt. They are simply removed from two different tensioners, much easier than some cars that require stretching the AC condenser belt on to the pulleys and having to cut them if removing. The water pump and thermostat are not affected when changing the oil filter housing gasket. Dont perform the cooling work solely from the fact the belts are off so might as well do the job. It literally takes like 5 seconds to remove them.

However, if you are willing to do any cooling work I highly recommend doing all water pump, thermostat, expansion tank, hoses, replace pulley, and CCV in one shot. You probably can get away with just water pump and thermostat alone but those hoses and expansion tank do eventually fail because they get insanely brittle. The mileage you are at it makes total sense to tackle the entire system since roughly between 100,000-150,000 miles its highly recommended to replace the entire system. I also recommended doing the CCV at the same time as the cooling refresh because there is one plastic cooling tube that runs underneath the intake manifold that should also be replaced with all the hoses since that tube eventually cracks. The pulley i also hear can crack if not replaced during the overhaul, which is why i recommended that. Some cooling kits come with hoses, pulley and expansion tanks all together. With the intake manifold off it makes replacing the CCV a simple, simplleeee job. The big cost is going to be the removal of the intake manifold.

Thanks that's really helpful. Sounds like the filter housing gasket fitting will be pretty expensive so I will renew the water pump with the cooling work later on and will certainly renew the CCV. I've looked back through old invoices and I had the expansion tank replaced in 2018 and also found an invoice for 'Replace faulty thermostat housing £160', presumably this would include the thermostat itself?

 

[caius]

also found an invoice for 'Replace faulty thermostat housing £160', presumably this would include the thermostat itself?

Correct, they come as one unit. Confused me when I was looking to renew mine and couldn't find the thermostat separately.

 

[colb]

Oil Filter Housing gasket is preety straightforward, have done mine and another members this year. Air Filter housing out and alternator taken out and then its easy to remove the housing and replace the gasket. They do go hard and brittle with age and repeated heat cycles just like the cam cover gaskets do. Belt removal is easy by putting a socket on the tensioners and using a long breaker bar to take the tension off so the belts can be removed. Just make a drawing of the belt route so you put it on correctly when putting them back on. Depending on condition of the belts it might be prudent to replace them as well. As to water pump and thermostat depends on mileage and if you think its prudent to renew them whilst you have access to them. Age of the car it might be worthwhile changing them whilst its stripped dowm.
Probably best to remove the undertray off so you can get at the belts from underneath as well as from the top, makes it easier to remove and reintall them.

 

[Gregory_tolson]

Yeah, i did the oil filter housing gasket on my own also. It was a pretty easy job, though that alternator was a slight pain to remove and to put back on. The sleeve the bolts are held was painful to get the thing in and out. 50s kid on youtube has an amazing video on how to do it since the M54 is also in the 3 Series. Only difference is his car has the hydraulic power steering versus our electronic power steering. And the air intake and fan setup is a little different but doesnt affect the process of removing it. [youtube]https://www.youtube.com/watch?v=zC_cmsX68Ok[/youtube]