Can a rod bearing spin on startup?

[pete914]

No word yet! I'll ask about the tensioner while we have the valve cover off (it's coming off tomorrow). For what's it's worth the engine hasn't made any noises on cold startup for me before this.

Thanks for the link, I sent away for an oil test kit although I feel like this is just going to stress me out more. LOL.

It would be awesome if were just a loose spark plug!! However, I feel like it would have made more vibration on the valve cover. I didn't feel anything specific.
I'll hopefully have an update tomorrow. Fingers crossed gents!

[pete914]

OK, head is off. My mechanic says source of the noise is a valve shim broke loose and destroyed one of the exhaust cam lobes. It also caused gauging and damage to the cylinder head housing. He said the valve clearance was way too loose and allowed the shim to come out. He said everything else looks good. He saw no evidence of oil starvation.

So, it looks like at a minimum I need a new exhaust cam, new cylinder head housing, and a valve clearance job. Could anyone help me out with a valve shim kit exchange? Suggestions for parts sourcing? I know I'm going to have to go remanufactured.

I see this for sale, anyone use this company?

http://parts.bmwofbridgewater.com/p/...121309891.html

http://parts.bmwofbridgewater.com/p/BMW_1991_m3manualcoupe/Housing/43825187/11121308424.html

I guess it could be worse but this is still pretty bad. I should have dropped the car off at his shop and had a valve clearance adjustment pre purchase inspection. Looking back the engine was pretty noisy but I assumed that was the nature of this motor. Beginners mistake.

[Todd black 88]

Wow, not what I expected to happen at idle start up. Not all that common to spit a shim at such a low rpm.

Sorry to hear the news. I am sure there are lots of folks with stock cams squirrelled away that can help you out.

[pete914]

Todd, my thoughts too. WTF??? I wonder if it "stuck" to the cam lobe and a cold engine allowed just enough extra clearance to knock it out on startup. Here I was hoping to have some nice drives this fall in the blue ridge mountains before winter sets in. Instead, now I'll be working weekends to pay for my oversite.

If anyone has parts they want to sell, trade +cash (b/c they are a machinist,etc) Please hit me up. Thanks everyone for their input.

I read a volvo shim kit is just fine for the S14? Comments?
http://www.partsgeek.com/6h8rct7-vol...+W0133-1604802

[pete914]

I know I'm blowing up my own thread, but here is a video of the motor running before the cam failure. This is after 3 hours of highway driving on the way home from TN. I feel like I can hear the tappets pretty well and even one that seems extra loud. What do I know though.
I remember feeling like it was a little "jangly" sounding but remained unconcerned as I was blinded by my excitement...

https://drive.google.com/open?id=0B9...HJRMi1LWFFOS0U

[jimmy p.]

Volvo shims work perfectly, I have been using them for all the years I have owned S14s, in all my S14s. I have never purchased a BMW shim.

If you post a WTB for a stock cam you will probably get 10 offers in the first day. They are plentiful.

The head,,, thats another issue. That will be expensive.
So there was damage to the head and cam box?
Those are two separate pieces. I can understand damage to the cam box, but I am trying to figure out how it damaged the head itself.
You want to clarify the damage with your mechanic, or post pics of what the damage is if your mechanic is not an S14 knowledgable guy.

I have heard of S14s throwing a shim out, its rare to hear about, and going by the few I have heard of its usually been on tracked cars at high RPM.

[Ironhead]

I've heard of thrown shims too....but I have always wondered how that can happen. The valve clearance would have to be something more than 10X over spec. Seems impossible, but clearly it is not.

Sorry for the bad news OP....I guess it could have been worse....but not much worse I suppose.

[VintageBMW]

Sorry to hear about the damage. I destroyed a valve, which I believe was also due to poor valve adjustment. Mine was much more costly than yours will be, engine was very tired and worn, so decided to do a 2.5 build

I have both stock s14 cams sitting in my parts cabinet, let me know if you are interested and would like some pictures. Not sure what they are worth, but shoot me an offer if you end up needing them.

Don

[pete914]

So far the damage seems to be limited to the Cam housing not the lower part of the head. I will double check with the mechanic though.
Great news about the Volvo shims, I'll order those.
Finally, I'm not sure the cams are stock. Should I replace both while I'm in there?
I hear timing chain tensioner should be replaced with the e36 unit. Any other preventative stuff that should be addressed?
I will post up a WTB

Vintage: Thanks man, I'm feeling really bad at the moment. What a first week of ownership of my dream car :(

[Ant's m3]

wow very interesting. Sorry to hear this. But you'll be good to go come spring time. I would highly recommend replacing the tensioner & guides for sure IF you have no documentation on them being replaced. Also might as well tackle fuel lines, vacuum hoses & intake gaskets. exhaust mani gaskets too, shit the list keeps going let me stop lol

[jimmy p.]

I don't think you "need" to replace the other cam if its not worn or damaged,,,because most likely what you will be replacing it with is another used cam.

BUT,,, what I would do is check everything with a fine tooth comb because with the rarity of an S14 throwing a shim out, especially at that low of an RPM I would search my ass off for any other deferred maintenance on that car. As Ironhead stated, that valve clearance has got to be WAY out of line for that to have happened to you.

My concern is what else in there was ignored considering the amount of dicking around one normally has to do with a tappet depresser, and a magnet, and sometimes compressed air just to get the damn things out during normal servicing.

Edit: Also god to hear the damage was confined to the cam box, that will (should) prove to be less expensive than a head.

[HANDBLT]

the only thing I can think of that would allow a shim to come out is for that valve/bucket to stick down, then when the cam lobe came off of it while it was stuck or slowly moving back to rest, the piston coming up hits the valve and kicks the shim out before the lob can come around again? that was an awful noise.

T

[Az in Oz]

I have an exhaust cam in good condition that you can have for free. ...just got to get it to the US. Let me know and I'll find out a shipping price.
Aaron

[Dave @nz]

Full credit to you for getting it professionally check out asap, not the best way to start M3 ownership. The video clip of your M3 on the drive home did sound quite noisy with a inconsistent idle, probably due for a good tune and going through while it is in the shop.

[Chris W]

Sorry for your loss. Could the engine oil have been a contributing factor? I thought the speculation was that an S14 using modern engine oils with insufficient Zinc (ZDDP) would occasionally kick a shim out.