Cannot unscrew oil filter housing cap - BMW E46

Joined
May 9, 2003
Messages
9,282
Location
Fayetteville, NC
So like I stated in a separate thread, I had my last OC done at the dealer on my 2005 E46 and they put the incorrect oil (0w/30 FE) and I decided to change it myself. (I usually do OCs myself on this car but once in while I do take it to dealer when i have a coupon).

This E46 has the oil filter housing on top of the engine.

So I got my oil and the mityvac ready and used the usual oil filter cap tool with my 3/8 wrench and found that... I cannot loosen the oil filter housing cap AT ALL. I have always used the same tools and never had a problem with it. After some trying and no luck I was afraid I would damage the actual housing and/or the cap, I just gave up and changed the oil anyway, without changing the filter of course (the filter only has like 900 miles on it, so i am not worried about the filter really - just wanted to get the 0w/30 FE out and replace it with Castrol Edge 0w/40).

No doubt the dealer service guy has overtightened the filter housing cap. (The housing cap has 25 Nm stamped on it)

What shall I try next? should I just get another OC at the dealer and let them deal with it? I hate to waste the $ on another OC though. I don't want to ask them just to change the filter because I am afraid they would blame ME for it, if they break it while trying to open it.

Is there anything I can try? (I did not try it with the engine warm, which i have seen suggested on forums - IDK if that plays a big role but it might?). Get a long 3/8 inch breaker bar and re-try? My 3/3 socket wrench is rather small. 8 inches max length probably. I don;t know how hard I should try though.... the cap of the filter housing is itself is not an expensive part, but I'd hate to break it. It is also not an ideal location to spray any type of penetrating oil/ WD 40/ PB blaster etc, and idk if it would even reach where the cap meets the housing...
 
Use impact force not twisting force. Either a ratchet and socket or box end wrench and tap the end of it with taps from a plastic or dead blow hammer.
Do not beat the hades out of the thing just small bumps, it will come loose. Be sure to lube the new O ring with engine oil.
 
^^^^^^^^^^^^^^^^^^^^^^^^^


If anybody I'd listen to on here on this type of circumstance or just about any other... I'd listen and do as Trav as advised...
 
I have an E46 and E90, both with the same style oil filter housing. IIRC, the housing cover is supposed to be 18 lb/ft, and lubricate the O-ring as Trav says. Importanty, the O-ring gives in the groove, not against the lip of the plastic housing.

As far as removing, use a 6 point 36mm socket if you can. Buy one if you have to. With the cover being so tight, a 12 point socket risks rounding the nut edges more than a 6 point. Do NOT use an adjustable wrench or anything like that.

With the car still operational, do not attempt until you have a 6 point 36mm socket (or at least a 12 point socket). And, yes, they did use the wrong oil but it won't hurt the car if you wait a few days to change it.

If you really must, drain the oil but leave the filter alone until you get a 36mm socket. The filter cover is readily available and relatively inexpensive so I'd order a new filter cover. Wait until you get the socket and cover before doing anything. I hope your aluminum oil pan is not stripped from the drain bolt being over tightened. 18 lb/ft for the plug, I am certain of that.

Scott
 
Does a hammer and screwdriver work with cartridge filter housings?
lol.gif
45.gif
 
Originally Posted by SLO_Town
I hope your aluminum oil pan is not stripped from the drain bolt being over tightened. 18 lb/ft for the plug, I am certain of that. Scott

The oil pan bolt on my E39 is designed to crack and leak before the pan is stripped. I can't say whether that works because I've neither stripped the pan nor cracked the plug (ie have always used a torque wrench).

I'd take it back to the dealer and point out that the oil filter housing cover has been over-tightened and ask that it be loosened and torqued properly. As that is a correction of a just completed job there should be no charge. If they want to know how you know, tell them you had to change the oil to the proper grade and leave it at that.

If you don't want to do that, I think the advice you've received is good, get a proper 6 point socket and a replacement cover before tackling it yourself. I also like Trav's idea of using impact as well.
 
Originally Posted by Alfred_B
Take it for the next oil change to the same dealer
lol.gif



I recently have the same problem with my son's RAV4
after 2 years of free oil changes.
I did the first oc at 5 k.
The service writer says we haven't seen the car since 20k (has 25k on it). Toyota specs 10 oci.
They build up pressure,its your car your problem.
So would you trust them to change that filter?
 
Mechanics who do not lube O ring or tighten to the point where you cannot loosen it up, should be banned from approaching any vehicle.
I think Trav is spot on. Just be patient with it.
 
And people wonder why dealers and quick lube places get a bad rap for oil changes and other services.
31.gif


Go with Trav's advice, just make sure you have the right socket.
 
Same thing on a MINI R53 that I take care of. The one time in the last 10 years where the oil was changed somewhere else a mad gorilla tightened the oil filter cap. On the MINI it's behind the engine so I typically use a 36mm 6-pt Lisle socket, extension, and a u-joint. I had to break out the 24" breaker bar to get it loose and I was fearful of the u-joint snapping.

The other stupid thing about this engine with the automatic transmission is they had to move the engine a smidge to the right to make room. This means the oil filter can't come out the top anymore...the steering wheel needs to be turned full-lock left to get it out the bottom!
 
Thanks for all the advice, really appreciate it.
Will try to address some of the things suggested:

To all who suggested getting the filter cap socket:

I Already have been using the 6 point 36mm socket
--That's what I have used for all of my previous oil changes for years with my 3/8 socket wrench. (that's what I meant by "oil filter cap tool" in the OP, sorry my terminology wasn't very clear)
Just that this time I cannot get it done no matter how hard i try.

I did try lightly using a rubber mallet on the end of the ratchet like Trav suggested. But I will give it another try, and try harder. Perhaps I wasn't using the correct technique.
And good tip on having a spare filter cap on hand. Should have done that years ago anyway, but I never had a problem with it before so....

I WAS able to change the OIL using MityVac. Just couldn't change the filter.

The tightening spec is stamped on the filter cap: it is 25 Nm.
I always lube the O-ring, and know exactly where to seat it. Beginning to suspect that the monkeys at the dealer either didn't use it at all but that would make oil leak out of housing, no?), or perhaps seated it wrong...

If all fails I am just going to take it to the dealer again.

What do you guys think about warming up the engine? Will that make any difference? (My OC attempt was done with engine cold, but on a very hot day)


Will update soon.
 
Last edited:
Is the cap plastic and the housing aluminum? Hopefully so. Worst case the cap will break.

As much as I don't enjoy my DIY oil changes sometimes, this is precisely why I continue to do so.
 
Originally Posted by JTK
Is the cap plastic and the housing aluminum? Hopefully so. Worst case the cap will break..

Correct - it is plastic and housing metal. But i want to "secure" the housing itself before I wrestle with the cap again - perhaps wifey can grab it with an oil filter wrench and exert some counter-torque or at least hold it tight: I don't wanna "turn" the whole housing WITH the cap and break the housing.
 
Last edited:
Like Trav says. I'm not a big guy, I learned long ago, impact is my friend. A simple controlled hit to the wrench end with a hammer will knock it loose. Also 8" wrench is pretty short. Go longer if possible.
 
Will try soon again. I think most of my fear is re: the housing itself. Perhaps I should wait until I have a spare filter cap....
Yeah I need to get some new wrenches of differing lengths - been thinking I need to do that anyway.
 
Last edited:
Back
Top