Help!...Missing Bolt on N55 Oil Filter Housing?

[bosstones]

I'm finally getting set to replace the OFGH on my X1 (N55) and was curious if I could see the PITA bolt under the intake manifold. There appears to be a threaded hole on the OFH that I can see just past the bottom corner of the air box. The oil residue on the front face of the flange that has this hole doesn't show evidence of a bolt head having been present for quite some time. However, although hard to see, the hole appears to be threaded but I can't make out if there is a sheared bolt. There appears to be at least half an inch of nothing so any bolt that should have been there would had to have fully backed out and gone who knows where (eek...).

Note that, in my pic, I haven't removed anything other than the oil filter and cap since I'm changing the oil at the same time.

Is this where the 3rd bolt (M8x43) is supposed to be? Looking at the diagram on FCPEuro, it appears so...

Can someone w/ a N55 take a peek and maybe post a pic of what they see? Nothing has to be removed to see this. It is just lifting the hood and looking in between the filter housing and (stock) air box towards the engine.

[NocheDeZippeh]

I don't know what that hole is for, but my N55 has it too. I believe the bolt you're looking for is above it about an inch or so, kind of hiding behind the wiring harness (see attached pics).

[bosstones]

Originally Posted by NocheDeZippeh

I don't know what that hole is for, but my N55 has it too. I believe the bolt you're looking for is above it about an inch or so, kind of hiding behind the wiring harness (see attached pics).

Thank you!!! That's a load off my mind. On the plus side, that location would be a lot easier to access.

Seems I missed that the housing bolts are supposedly 1 time use so I need to order those.

For those that DIY'd their OFHG, did anyone not drain the oil first? I need the car during the week so I'll be adding oil and new filter today but tackling the OFHG next weekend.

[NocheDeZippeh]

When I did my OFHG (~40k miles ago), I changed the oil/filter (and the coolant), but I'd think if you replace any significant amount of oil lost during the gasket surgery, you would be ok.

There has been some discussion on the E90 N55 board about a theoretical correlation between fixing a leaky OFHG and subsequent spun rod bearings - some say you should prime the oil afterward.

https://www.e90post.com/forums/showthread.php?t=1513898
https://www.e90post.com/forums/showthread.php?t=1871244

I didn't do any priming, just changed the oil and filter like normal, and I've been ok, but it is food for thought.

[bosstones]

Originally Posted by NocheDeZippeh

When I did my OFHG (~40k miles ago), I changed the oil/filter (and the coolant), but I'd think if you replace any significant amount of oil lost during the gasket surgery, you would be ok.

There has been some discussion on the E90 N55 board about a theoretical correlation between fixing a leaky OFHG and subsequent spun rod bearings - some say you should prime the oil afterward.

https://www.e90post.com/forums/showthread.php?t=1513898" rel="ugc" target="_blank">http://<a href="https://www.e90post....?t=1513898</a>
https://www.e90post.com/forums/showthread.php?t=1871244" rel="ugc" target="_blank">http://<a href="https://www.e90post....?t=1871244</a>

I didn't do any priming, just changed the oil and filter like normal, and I've been ok, but it is food for thought.

Ended up tearing things out last weekend but progress stalled during the week due to the work week so I also ordered a few replacement bits just in case (eg, radiator plug+control sleeve, some of the underbody shield screws since 2 were missing, etc...). Still need to remove the cover thing over the VC and then remove the intake manifold.

Serpentine belt looks okay (no oil on it) so I'll hold off on that. It appears the bulk of the leak is from the valve cover gasket.

Ended up draining the oil again last weekend and will do the coolant today.

Several oil changes ago, I started putting a little fresh oil in with the filter. I had come across doing that somwhere and thought it made sense.

[wheela]

Originally Posted by NocheDeZippeh

When I did my OFHG (~40k miles ago), I changed the oil/filter (and the coolant), but I'd think if you replace any significant amount of oil lost during the gasket surgery, you would be ok.

There has been some discussion on the E90 N55 board about a theoretical correlation between fixing a leaky OFHG and subsequent spun rod bearings - some say you should prime the oil afterward.

https://www.e90post.com/forums/showthread.php?t=1513898
https://www.e90post.com/forums/showthread.php?t=1871244

I didn't do any priming, just changed the oil and filter like normal, and I've been ok, but it is food for thought.

I had my OFHG replaced, and a month or two after I got paranoid when I read about potential rod bearing issues after OFHG replacement. I brought my car back for a weird vibration and they specifically mentioned they do the oil priming after OFHG replacement to prevent this issue from happening. It's obviously not certain you'll spin a bearing if you don't prime after OFHG replacement, but I think you're taking a bigger gamble if you choose not to do the priming afterwards.

In my case, I was just being over-sensitive to NVH looking out for rod bearing issues. There was nothing wrong with my car, the tires were just creating more NVH when it got cold for winter, haha! OFHG was replaced late September.

[NocheDeZippeh]

I may have ducked a bullet by not priming the oil pump after I did my OFHG. Wasn't even aware of the issue. Probably should have bought a lottery ticket that day too . Here is the relevant TSB:

https://www.tsbsearch.com/BMW/SI-B11-09-15