[fenixxishot]

I would like to begin by apologizing as this post is quite long however I will post a cliff notes version at the end and if you are so inclined you may read my adventure please review.

It begins with the seemingly uneventful; I was experiencing the common oil filter housing/ oil cooler housing leak. I was not tremendously concerned as it was more of a seeping than a true leak I believed so I let it persist as I was NOT going pay a dealer almost 1k for the repair I knew I could do especially when the part was only $15. Well waiting was a huge mistake.

I was informed of the oil leak by the dealer in August when I went in for a coolant flush, which was my ah hah moment as I realized why I was adding a quart once a month and why I occasionally smelled burning oil(very occasionally and no smoke, again why I wasn’t concerned). So I decided this would be a good project to take on during Christmas break a 1 quart a month oil leak is not a big deal.

Well at the end of October my Serpentine belt shredded and I immediately did some research and it seemed as a few people had the issue of the sub frame hitting the P/S pulley and damaging the belt causing it to shred. This was not the cause of my accident I thoroughly examined the P/S pulley and it had absolutely no damage.

That belt shredding caused another issue that I did not realize until yesterday. When our belts get wrapped around the crank pulley they damage the crank seal and in a worst case scenario can be sucked up into your engine causing you to lose your engine. The belt shredding was my wake up call to address the oil leak. I did the oil filter housing gasket swap and put a new belt on however oil still leaked and I was shocked I couldn’t believe it.
I had a buddy do the walnut blasting on my intake valves and asked him to change the gasket again as it appeared it was still leaking so he did and he cleaned the engine up very nicely so we could actually see if the oil leak had truly go away. Well after the car warmed up there was still a solid bit of oil dripping on the ground however it was not coming from anywhere near the oil filter housing. We realized that oil was leaking from the front crank seal/front main seal.

So we decide it’s best that I take it to a mechanic to have the seal replaced and I am absolutely freaking out because I have read about peoples belts damaging their crank seal and getting pulled into the engine requiring a completely new engine. As I am locating the parts (I recommend Phil at Revees he is a sponsor here I believe) I am told by Phil that a special glue and primer are required. He can get the glue but the primer Loctite 171000 is not available in the US he would have to have it shipped from Germany. I’m like I need this issue addressed ASAP so I call Loctite and after I get bounced to 10 different people I finally get and compound analyst who tells me there is no direct conversion available anywhere however he recommends a possible alternative as they have similar activating structures which is Loctite 7649.

On Friday I take everything to the mechanic to have the seals swapped out which sounds like a straightforward process, however the mechanic ends up spending about 10 hours to do it because it’s nearly impossible to remove the seal after it has been damaged. And the whole time I am hoping there are not pieces of my belt in the engine which after looking at the damaged seal I see how it is completely possible. Finally I get some good news the mechanic fishes up a camera and we rotate the crank and I see nothing on the timing chain I am relieved to say the least. And after a couple hundred miles of driving no oil leaking!!

Cliff Notes:
I put off address my oil filter housing leaking and that compounded into an issue that could have caused me to lose my engine please learn from my mistake and take care of this ASAP it truly is an issue that needs to be addressed very quickly.
I will post of a DIY for the oil filter housing gasket for the 335i it is a bit different than a 328i next time I have a chance.

[Bingobimmer]

Close call glad everything worked out. I will definitely keep this in mind.

[07lilredwagon]

thanks for sharing this....


one more thing to worry about!

JP

[bumere90]

damn, lucky you my friend
this whole thing could have turned out a nightmare
glad it worked out
bmw should address this issue

[StevenY.]

Wow, you really got lucky on this one.

[fenixxishot]

One of the additional underlying issues which helps to make this problem the perfect storm is the pulley design. BMW has 2 smooth pulleys in tandem which really helps the belt slide off when it gets even a little oil on. I plan to call bmwna and see where that call goes I don't expect anything to happen but if anyone has any recommendations let me know. I would further like to clarify this issue identifies at least 2 complete design flaws. 1) the two non lipped pulleys in tandem which allows the belt to slide off 2) the ability for the belt to get pulled up into the engine.

[StevenY.]

Originally Posted by fenixxishot

One of the additional underlying issues which helps to make this problem the perfect storm is the pulley design. BMW has 2 smooth pulleys in tandem which really helps the belt slide off when it gets even a little oil on. I plan to call bmwna and see where that call goes I don't expect anything to happen but if anyone has any recommendations let me know. I would further like to clarify this issue identifies at least 2 complete design flaws. 1) the two non lipped pulleys in tandem which allows the belt to slide off 2) the ability for the belt to get pulled up into the engine.

I wonder if this can potentially turn into a class action lawsuit followed by a recall. This is a serious problem and it's happened to many people.

[rorkor]

Originally Posted by 07lilredwagon

thanks for sharing this....


one more thing to worry about!

JP

A little less issue for the 328's but still a good thing to be aware of, the pully hitting the subframe is 100% a turbo issue.

OP: Glad this worked out for you, very close call. I have seen a lot more of these scenarios pop up lately, seems we are seeing the 5 year longevity issues start to arise.

[MrDummy]

Ditto op glad u got it straightend out.

And man I'm glad I got non turbo...

[fenixxishot]

Originally Posted by MrDummy

Ditto op glad u got it straightend out.

And man I'm glad I got non turbo...

This can easily happen to a non turbo. The issue arose from a oil leak from the oil filter housing which all e9x base models have as well as all n54 derived vehicles.

[E90Flossin]

Thanks for the heads up! We shouldnt procrastinate in anything especially when it comes to our vehicles. Lovin the cliff notes also haha

[speedworks]

Maybe I missed it - what does a leaky oil filter housing have to do with a broken belt?

[rorkor]

Originally Posted by speedworks

Maybe I missed it - what does a leaky oil filter housing have to do with a broken belt?

The oil drips onto the belt & pulley's causing the belts to slip at high rpm. There are no lips/guides on several pulley's causing the belts to shred and mangle the front end of the engine bay. There are several threads running right now for specific model issues around this.

[fenixxishot]

Originally Posted by rorkor

The oil drips onto the belt & pulley's causing the belts to slip at high rpm. There are no lips/guides on several pulley's causing the belts to shred and mangle the front end of the engine bay. There are several threads running right now for specific model issues around this.

Thank you. This is exactly correct.

[rorkor]

Originally Posted by fenixxishot

This can easily happen to a non turbo. The issue arose from a oil leak from the oil filter housing which all e9x base models have as well as all n54 derived vehicles.

Yes it can happen to any car, not just bimmers. It is less likely in a NA engine as we run lower pressure and slightly lower temp than the turbo's in both the N54 & N55. An oil leak should always be addressed in a timely matter which was the point the OP was making, regardless of engine type.

[4cfd bmr]

Originally Posted by fenixxishot

I would like to begin by apologizing as this post is quite long however I will post a cliff notes version at the end and if you are so inclined you may read my adventure please review.

It begins with the seemingly uneventful; I was experiencing the common oil filter housing/ oil cooler housing leak. I was not tremendously concerned as it was more of a seeping than a true leak I believed so I let it persist as I was NOT going pay a dealer almost 1k for the repair I knew I could do especially when the part was only $15. Well waiting was a huge mistake.

I was informed of the oil leak by the dealer in August when I went in for a coolant flush, which was my ah hah moment as I realized why I was adding a quart once a month and why I occasionally smelled burning oil(very occasionally and no smoke, again why I wasn’t concerned). So I decided this would be a good project to take on during Christmas break a 1 quart a month oil leak is not a big deal.

Well at the end of October my Serpentine belt shredded and I immediately did some research and it seemed as a few people had the issue of the sub frame hitting the P/S pulley and damaging the belt causing it to shred. This was not the cause of my accident I thoroughly examined the P/S pulley and it had absolutely no damage.

That belt shredding caused another issue that I did not realize until yesterday. When our belts get wrapped around the crank pulley they damage the crank seal and in a worst case scenario can be sucked up into your engine causing you to lose your engine. The belt shredding was my wake up call to address the oil leak. I did the oil filter housing gasket swap and put a new belt on however oil still leaked and I was shocked I couldn’t believe it.
I had a buddy do the walnut blasting on my intake valves and asked him to change the gasket again as it appeared it was still leaking so he did and he cleaned the engine up very nicely so we could actually see if the oil leak had truly go away. Well after the car warmed up there was still a solid bit of oil dripping on the ground however it was not coming from anywhere near the oil filter housing. We realized that oil was leaking from the front crank seal/front main seal.

So we decide it’s best that I take it to a mechanic to have the seal replaced and I am absolutely freaking out because I have read about peoples belts damaging their crank seal and getting pulled into the engine requiring a completely new engine. As I am locating the parts (I recommend Phil at Revees he is a sponsor here I believe) I am told by Phil that a special glue and primer are required. He can get the glue but the primer Loctite 171000 is not available in the US he would have to have it shipped from Germany. I’m like I need this issue addressed ASAP so I call Loctite and after I get bounced to 10 different people I finally get and compound analyst who tells me there is no direct conversion available anywhere however he recommends a possible alternative as they have similar activating structures which is Loctite 7649.

On Friday I take everything to the mechanic to have the seals swapped out which sounds like a straightforward process, however the mechanic ends up spending about 10 hours to do it because it’s nearly impossible to remove the seal after it has been damaged. And the whole time I am hoping there are not pieces of my belt in the engine which after looking at the damaged seal I see how it is completely possible. Finally I get some good news the mechanic fishes up a camera and we rotate the crank and I see nothing on the timing chain I am relieved to say the least. And after a couple hundred miles of driving no oil leaking!!

Cliff Notes:
I put off address my oil filter housing leaking and that compounded into an issue that could have caused me to lose my engine please learn from my mistake and take care of this ASAP it truly is an issue that needs to be addressed very quickly.
I will post of a DIY for the oil filter housing gasket for the 335i it is a bit different than a 328i next time I have a chance.

Going through this exact ordeal at the moment right now! How much did the "stealer" charge you to replace the crank seal out of curiousity?

[TwinTuning]

Wow. Thanks for heads up.

[parabola]

I replaced belt tensioner on my 328 for the same reason. The belt was riding on the edge of the pulley and tensioner was failing for sure.
Having heard before of the situation where belt get sucked past the seals into an engine I had the dealer replace it under warranty.
Seems like tensioner failure is common, at least in my case on N51/52 engine.

[techietaichi]

WHEW! That story had ME sweating bullets! Glad you got that sorted out OP.

[AWDBooSTIn90]

I bought a new belt after reading a thread like this a few weeks ago. Now im wondering if i should change the tensioner also.

Has there been alot of belt tensioner failures on early n54's?

Mine still has good tension, belt never slips and everything looks ok...

[N8N]

I had my tensioner replaced last oil change - about 85K miles.

The SA at the dealership told me that it was not lack of tension or failing bearings that was causing the belt issues but it was fore-aft play on the "arm" that was causing the belt to walk off the other pulleys and shred itself. Apparently my (original) tensioner was starting to show some signs of this although the belt itself was fine.

[Eat.Sleep.Race]

I read about the belt being able to get into engine a few months ago, if it looks worn replace it!!