[sav_e92]

So I made a pretty big mistake today while replacing my exhaust vanos solenoid. I was attempting to seat the rubber o-ring into the engine before inserting the solenoid (after a few failed attempts to slide the solenoid into the engine with the o-ring on the solenoid) and it fell into the engine.

So now I am faced with a dilemma. A search of past posts reveals a short thread where the prevailing opinion seems to be that a small rubber o-ring is not a big deal compared to the mechanics of the engine, will likely land in my oil pan, and is not likely to make it through my oil pickup tube. But that's a pretty scary "maybe."

My current plan is to buy a boroscope tomorrow and take a look. If the o-ring isn't stuck on the timing chain somewhere, I'll presume its in the oil pan. If the logic is correct that it won't make it through the pick up tube, I'll get another o-ring, finish installing my solenoid and call it a day. If its stuck where it shouldn't be, I'll try to fish it out and if I can't, I'll try to knock it down into the oil pan.

Or... if I really need to, I'll have the car towed to a shop and pay an exorbitant fee to have the engine disassembled such that it can be retrieved. What a shame.

What do you guys think? Will this o-ring be the death of my n52? Does my plan sound reasonable?

[mapleleaf1773]

Damn dude, sorry about your luck. My condolences toward your situation. I hope everything works out for you.

But to give you a thumbs up or thumbs down, thats above my paygrade.

Best of luck brother

[sav_e92]

Originally Posted by mapleleaf1773

Damn dude, sorry about your luck. My condolences toward your situation. I hope everything works out for you.

But to give you a thumbs up or thumbs down, thats above my paygrade.

Best of luck brother

Thanks man.

For others that may read this - here are some other threads I found addressing this:

https://www.e90post.com/forums/showthread.php?t=1037606

https://www.bimmerfest.com/threads/n...oblem.1253874/

https://www.e90post.com/forums/showthread.php?t=1009451

Here's a thread about a dropped bolt...
https://www.e90post.com/forums/showthread.php?t=1245317

[E92_William]

How did you drop that in there? It seems pretty hard unless you put it in place and bumped it well with the solenoid. Either way this o ring definitely landed probably all the way down by the sprocket for the crankshaft. You can see in this picture how the chain is setup kinda. I would like to check for you but then I'd have to start taking apart this thing in the stand. I think the bore scope is a great idea and then you could just fish it out with a stiff metal cable or something. Best option

EDIT: I just tried to put the solenoid back and realized exactly how you dropped it in lol. Very easy to do actually if you don't put the O ring right on that step area that it has in the middle of the solenoid. That would have sucked big time. Someone has to have had this happen before and not even realized they're missing the o ring.

[sav_e92]

Originally Posted by E92_William

How did you drop that in there? It seems pretty hard unless you put it in place and bumped it well with the solenoid. Either way this o ring definitely landed probably all the way down by the sprocket for the crankshaft. You can see in this picture how the chain is setup kinda. I would like to check for you but then I'd have to start taking apart this thing in the stand. I think the bore scope is a great idea and then you could just fish it out with a stiff metal cable or something. Best option

EDIT: I just tried to put the solenoid back and realized exactly how you dropped it in lol. Very easy to do actually if you don't put the O ring right on that step area that it has in the middle of the solenoid. That would have sucked big time. Someone has to have had this happen before and not even realized they're missing the o ring.

Yeah it was too easy to lose! I installed the other one by the same method so I figured I knew what I was doing. Had some fairly thick gloves on since the engine was still warm and I think that was part of the problem... couldn't exactly feel when the ring was seated and then it was too late.

I'm planning an early morning trip to Harbor Freight (in my gf's car) for a bore scope and will post my results.

I also found this picture of an e90 oil pickup and judging by the screen and its surface area, I'm feeling pretty certain that this o-ring wouldn't cause any problems if it is indeed in the oil pan. If it landed there intact, I don't think it could actually fit into the return tube judging from the picture.

[E92_William]

I mean I'm sure it won't restrict oil flow too much if it gets stuck there, my concern would be it being in the oil in the pan and somehow landing in the chain. Could make it skip a tooth maybe or break up and get stuck somewhere

[Brian86]

An O-ring won't hurt the engine. It'll probably just sink to the bottom of the oil pan.

Even if it gets caught up in the timing chain it'll just get chewed up into little bits. No way an O-ring is going to cause it to skip or jump.

There isn't enough rubber mass to clog the oil pickup screen, fine pieces that go through won't hurt the oil pump, and the rest will get caught in the filter.

Now if you had dropped a screw in there, that's a different story.

[sav_e92]

Ok so after a good look with the boroscope I can say with 90% certainty that the o-ring has not landed on the timing chain. I could clearly see the lower sprocket area and it looked clear.

I couldnt exactly tell how much space there was between the chain and the engine for it to fall through but it looked like enough... I couldn't quite get the camera through there without applying more force than I was comfortable with. Current plan is to pick up a new o-ring tomorrow and button everything back up.

[Sav.]

I doubt it will do much harm. My N54 sucked my serpentine in through the front main seal and it was shredded quite fine, most of it got stuck in the mesh in the oil pick up from what I could tell. I doubt an O-ring would do anything at all, worst case scenario, maybe if/when it disintegrates might make it's way into your vanos? You don't have turbos so I don't believe there is much you could damage.

[sav_e92]

Just to close this one out, I got a new o-ring today, installed my new solenoids and fired it up. No issues after a lengthy test drive (and so far no more SES light too).

I'm calling this one resolved.

[bluewater328]

Dealer once screwed up the oring on the vanos for me. All I saw was a pool of oil spitting out the front of the engine. Glad it at least threw a light for low oil to let me know.

Glad you got sorted....but yeah, I wouldnt imagine the oring would do much, but better safe than sorry.

[bluewater328]

Originally Posted by E92_William

How did you drop that in there? It seems pretty hard unless you put it in place and bumped it well with the solenoid. Either way this o ring definitely landed probably all the way down by the sprocket for the crankshaft. You can see in this picture how the chain is setup kinda. I would like to check for you but then I'd have to start taking apart this thing in the stand. I think the bore scope is a great idea and then you could just fish it out with a stiff metal cable or something. Best option

EDIT: I just tried to put the solenoid back and realized exactly how you dropped it in lol. Very easy to do actually if you don't put the O ring right on that step area that it has in the middle of the solenoid. That would have sucked big time. Someone has to have had this happen before and not even realized they're missing the o ring.

Damn, that block looks clean. I dont have a lot of dust or rust in my region, but mine doesn't look this nice.

[E92_William]

Originally Posted by bluewater328

Damn, that block looks clean. I dont have a lot of dust or rust in my region, but mine doesn't look this nice.

I tried cleaning it up a bit since the last thing I need on a stand is a greasy and grimy engine to touch, but I'm sure the one in my car isn't like this