Part Number Help! Intake cam bearing cap E5 (broken)

[jsnppp]

Ok, so, I have the cylinders in the wrong order. Cylinder 4 is closest to firewall. Cylinder 1 is next to radiator.

So, in my video I pulled cylinder 4 at the coil but cylinder 1 at the plug.

I still believe I have a cylinder 4 problem. I will test out the plug wire again and also check sensors and verify timing.

It also just occurred to me that possibly in the blunt force trauma of the cam break maybe the timing chain stretched. I will visually inspect it when I verify timing later today.

Good times.

Jason

[jsnppp]

Verified spark at the plug.

I'm starting to think that it's a mechanical issue. Like perhaps one of the intake valves is bent/etc.

Leak down test!

[jsnppp]

Magnet picked up a small piece of metal that looks like may be part of the valve keeper. Sooooooooo....

Leak down test this afternoon. I'm guessing the head has to come out.

[jsnppp]

So, here are photos of what I found in cylinder 4. Anyone have ideas what it is? Piece of valve? Valve keeper? It's only one piece, taken from two angles. Scale: about 1/4 inch.

It's steel, picked up by magnet.Doesn't look like cylinder. Can't be piece of spark plug.

Leak test tomorrow and then I'll pull intake cam and see if anything wonky is with cylinder 4 valves.

THoughts welcome.

[bmwman91]

Hmm, well that is not ideal. I am trying to think of what ferrous items could get into the cylinder, and how. Maybe a valve seat came out of the head? There are some small steel sheet parts up around the lifters, like the valve keeper that you mentioned, but you would have to completely drop a valve all the way into the cylinder for any of it to get into there. That seems a bit unlikely. Maybe if a valve dropped part way it could have fallen through the guide into the intake port? That also seems sort of unlikely. But, at this point I think that pulling the head might be the best course of action.

[Hsquad12]

valve keeper

[jsnppp]

Thank you both. I went through a bunch of diagnostics (again) today. Leak down test interestingly showed about 12 ish percent. I may be doing it wrong so I'm not sure. Other cylinders are ok, but ranght up to 20 ish percent. Again, I may be doing it wrong..

Regardless, no matter what I do I find:

1. Spark plug is sparking. Verified visually and compared to other cylinders.
2. Fuel is reaching cylinder. Plug is wet when pulled. Also, new fuel injectors.
3. Idle is somewhat "chuggy". If rev up it smooths out considerably.

If I pull plug 4 (nearest the firewall, opposite radiator), while running, it has no effect. However, I can see it sparking when I hold boot near the plug.

I think something is wanged up in the cylinder. I did not notice valve keepers loose or any springs loose when changing the cams. But, then I didn't shake anything either.

Ok, I will pull the head. I too feel it's the next course of action. Fingers crossed it's not FUBARd and just is something "easy". I have to bring it somewhere to have new valve lapped, right? Not a home job I don't think.

I need to build the list of parts. Minimum new head bolts. Prob head gasket. Ugh!

Jason

[jsnppp]

I'll pull both cams first anyway and see if it's a valve keeper or something prior to pulling the head.

Oh. I did change the cam followers to the lighter version. However, can't see how that would do anything.

[bmwman91]

Good luck, I hope that it ends up being something simple. Sorry that this has been such an ordeal!

If pulling the plug for #4 makes no difference to how it runs (so it sounds like it runs on 3 cylinders) then I assume that a valve has dropped. I have had the misfortune of having an intake valve spring go out on a cylinder, and yes the idle is terrible but things seem smooth'ish (but really weak) when revved.

Fingers crossed that the valve stem bent and is keeping it up out of the way. If the valve head breaks off, then that would probably mean the engine is scrap (head would likely be toast, plus some bottom end damage), so it will be best to not run the engine any more until you can find out what is happening. Post up pics if you can as you go through things. If a valve has dropped, then you should be able to see it pretty easily when you pull the intake manifolds. When I lost the valve spring, a valve dropped but thankfully the stem bent and jammed it into the guide, so there was no major damage other than some light nicks in the piston crown which were filed out without removing it from the block. In fact, valve springs broke on 2 different occasions (this was on a custom built M42 engine) and there was no major permanent damage to anything. So, there is hope!

[TobyB]

how the hell would a random keeper get INTO the cylinder?

That's just... odd. Have you made any fresh enemies recently?

The other goofy thing is that chunks like that usually do 50- 100 revolutions
in the cylinder, munch hell out of the quench surfaces and piston crown, and then
get spat out or permanently embedded into something soft.
So why's it still in there?

All these questions and no answers...

t

[jsnppp]

A buddy with a couple of 318is came over and we went through it too. He did confirm everything I concluded as well - it's getting proper spark, has compression and appears to be getting fuel. Timing is good - it runs very smooth albeit on 3 cylinders!

He had valve keepers and a couple of valves and we compared that shard of metal and it's nothing like any of them. Not sure where it came from. Still could be a chunk of valve? Doesn't feel like it.

SO. Before I pull the head. I am going to pull intake and look at intake valves to see if something is amiss. I will also put the original fuel injectors back in.

If nothing is odd I am going to button it up and lightly drive it. It is possible too that it needs an italian tuneup. But gently.

I risk grenading the engine but it runs really well. Other than 3 cylinders. Ha ha.

I'll post what I find. Greatly appreciate your all inputs.

Jason

[jsnppp]

So -

1. I drove the car. Gently. Under load it felt exactly like a car running on 3 cylinders. No odd noises, clanks, or anything. I drove under 3k but a couple of times blipped up to 4500. About a mile of driving. Smooth and eager actually. Stupid car.
2. Removed the intake manifold. The intake valves appear to be in one piece and behaving correctly. By that I mean they open and close as engine rotates. I put a light in the cylinder and could see through the side of the head.
3. I toned out the fuel injectors. 2 and 4 are connected properly, 1 and 3 and connected properly.\
4. We checked compression on all 4 - 178-192 ish across all of them.

Didn't see anything wonky anywhere.

I then more closely inspected exhaust cam. From the top it feels like it's behaving as should. Cam followers going up and down. I haven't pulled exhaust manifold to see them visually. Really don't want to do that till I pull the head.

Intake valves on cylinder 4, my problem child:

[jsnppp]

Feels like maybe exhaust valves now?

Or I bolt it all together and run it at 6000 rpm for 10 min. :-)

[jsnppp]

how the hell would a random keeper get INTO the cylinder?

That's just... odd. Have you made any fresh enemies recently?

The other goofy thing is that chunks like that usually do 50- 100 revolutions
in the cylinder, munch hell out of the quench surfaces and piston crown, and then
get spat out or permanently embedded into something soft.
So why's it still in there?

All these questions and no answers...

t

No arguement on any of these points! It's possible it fell in when I was cleaning up the residue from the cam break and so didn't run in there for very long.

Intake valves "look" ok. Exhaust are question mark but it does have decent compression and my first ever leak down test did not show serious leakage.

My feeling is it's either fuel injector (don't see how - it's wet with fuel) or exhaust valve. But if exhaust valve I would think it not be wet from unburned fuel.

Puzzler.

[jsnppp]

Bolting intake back up. Checked timing and it's off. I don't think this is what is causing cyl 4 to not fire, but I'll fix it.




Also put back in my original fuel injectors. I swapped to mustang injectors (4 hole vs. 1 hole) when I was originally chasing the ticking noise.