How the hell did this happen?

[Vertigo]

Time to turn to the experts.

Background:

Back in December I completed my build by installing my head back on my motor. During this process I followed the BMW TIS @ workshop manuals using the proper torque specs.

During the install, I had at my disposal the BMW master timing kit.

Once the head was installed, I installed the cams by sliding the timing tool forks down the flats of each cam with the digital stamp visible from the
top. The impulse sending wheels (11367540442) holes aligned perfectly to the dowels on the timing tool that sits on the front ledge of the head. The special TTY Collar Screw (11367524954) were ordered new and torqued properly on both intake and exhaust gear units.


I've been trying to wrap my head around how this could happen. Not sure how this is possible but have a peek at this mess. The car was running just fine for the past few months. Just to provide a full picture this happend a few hundred miles after have vanos changes applied to help spool with my single turbo. Shortly after the Vanos changes were made I started getting "2A87 - VANOS exhaust – stiff; jammed mechanically". I deleted without issue and a few weeks later I started hearing a weird metallic tapping noise which sounded just like the old E46 vanos rattle issue. The rattle got worse and worse while my cold starts got longer and longer. I finally had enough and pulled the valve cover to discover this!






How is this possible?

From what I have been told about the way the VANOS units work...the solenoids allow oil to flow up into the vanos gear units which then decouples them allowing the vanos gear?? or Cam?? not sure which to no longer move in direct relation to the impluse sending wheel? Thinking about this it cant be right because this is double vanos which means the intake and the exhaust cam can move independent of one another even though they are connected by a chain and sprokets? In the situation above would not the timing chain have to stretch inbetween the exhaust gear and the intake gear to allow the exhaust cam to move further behind the intake cam? I would think that the cams themselves would have to be able to move independant of the cam gears somehow.

So now the real question is when re-installing is it as simple as re-aligning the cams back to being straight up and then slapping the timing chain back over the gear units or is the exhaust vanos gear unit stuck in a position that it should not be in and that I need to reset before setting the mechanical timing back once again?

Would it be safe to replace both Vanos solenoids, re-time, and done? Or do I need to get new Vanos Gear units as well? Thanks!

[Sticky]

Obama.

[joseph]

the only thing that I can think of is that the vanos unit/sprocket failed. Also unlikely but double check to make sure that intake and exhaust vanos units/sprockets are not swapped Ein= intake Aus= exhaust.

[Vertigo]

Could someone tell me if I am correct in assuming that during the installation process the position of the VANOS sprockets does not matter (I know there is an IN and EX which I installed correctly) but the sprockets position relative to the cam does not matter as long as the impulse sending wheels (11367540442) are timed correctly when tightening the cam to the sprocket, the sprocket to the sending wheel with the bolt?

[duracell8]

It does not matter where the vanos unit is in relation to camshaft during install. What did you torque the cam bolts at? IIRC, its 20 nm plus 180 degrees. It appears the cam moved in relation to the vanos unit like it was tighten enough. Remember the camshaft has resistance against the valve springs and the only thing securing it to timing chain is the bolt, no key way.

[Jduke]

I hope you get fixed with minimal impact to your wallet , etc.

[Vertigo]

It does not matter where the vanos unit is in relation to camshaft during install.

Good! That's what I thought!

What did you torque the cam bolts at? IIRC, its 20 nm plus 180 degrees.

I believe that is correct. I don't have the documentation in front of me at the moment though.

It appears the cam moved in relation to the vanos unit like it was tighten enough. Remember the camshaft has resistance against the valve springs and the only thing securing it to timing chain is the bolt, no key way.

And this is the key issue that I am trying to determine. Did the cam actually move as not intended due to mechanical issue or improper torque OR...OR is the cam just stuck in a phased position it would normally be able to return out of due to a faulty solenoid not providing proper oil pressure? My hope is the later, as then I would think I could just install a pair of fresh solenoids which would then provide the proper oil pressure to allow the exhaust cam to get phased back to its default position at idle/stop vs this retarded position it is in now.

[Livnpaintball2]

Obama.

LMAO

[duracell8]

The vanos units are sprung in one position, the default position, oil pressure over comes the spring pressure to move the cam in the opposite direction.. I would removed the ehaust cam and inspect the bearing ledges and lobes to make sure nothing is dragging or damaging, reinstall if all is correct and re-time the motor since this is recent head install. Could the vanos unit be bad, sure. Most likely not in my experience, but others may disagree.

[Sticky]

LMAO

Just wanted to bump it to get his post some attention and help.

[Vertigo]

Thanks Sticky.

I also ran across the following SIB and TEST PLAN BMW uses when encountering the 2A87 error.

"Ran test plan B1214-NG6NWA and still had mechanical faults after VANOS solenoidcheck was performed. Removed valve cover to check mechanical timing per test plan. Found mechanical timing was off. Per shop foreman replacement of VANOS adjustment bolts. VANOS solenoidsand timing chain tensionerto be performed. Replaced both adjustment unit bolts and correct mechanical timing of the engine. Replaced VANOS solenoids. Replaced chain tensioner. Cleared faults. Ran test plan to include check of VANOS solenoidsper previous test plan. All specs were met during plan execution. Test drive did not return concern."

So it looks like BMW is recommending to replace both bolts on the VANOS gear units, inspect the oil filter cap, inspect the bearing ledges, correct the mechanical timing, replace both Vanos Solenoid units, Replace the hook ring seals with the newly updated teflon versions on the end of the cam, fresh oil, and done. That's my plan.

[duracell8]

The bolts they are referring to are not the cinch bolts for camshaft adjusting unit to camshafts. They are the small aluminum ones on the back side, 4 per unit. BMW is having a recall on those bolts. Specific model years. What is year make and model of your car? The bolts loosen over time, or the head snaps off and the cams go out of adjustment.

[Vertigo]

The bolts they are referring to are not the cinch bolts for camshaft adjusting unit to camshafts. They are the small aluminum ones on the back side, 4 per unit. BMW is having a recall on those bolts. Specific model years. What is year make and model of your car? The bolts loosen over time, or the head snaps off and the cams go out of adjustment.

2008 e92 335i. I visually inspected those smaller bolts on each unit and they were all there. When I take the units off I'll check that they are all tight. Thanks!

[Jduke]

Did you get your car straightened out ?

[ronilrd]

Hey did this work out for you? I'm having the same issue.

[Vertigo]

After draining the oil i saw bearing material and then noticed that piston #2 was not coming to the top of the block deck like all the other pistons were. This was happening b/c piston #2 's rod bearing material was all gone. I've got the block all torn apart and has since purchased a new special block. I've got the Pure 2's installed and have been waiting about 4 weeks now for the "Available" VTT hotside chargepipe to arrive.

[The Ghost]

After draining the oil i saw bearing material and then noticed that piston #2 was not coming to the top of the block deck like all the other pistons were. This was happening b/c piston #2 's rod bearing material was all gone. I've got the block all torn apart and has since purchased a new special block. I've got the Pure 2's installed and have been waiting about 4 weeks now for the "Available" VTT hotside chargepipe to arrive.

Did you see if the rod was bent as well? The bearings are so thin, you'd have to have severe damage to be able to see the change is stroke.

Pictures! Good luck

[Vertigo]

Rod looked good. Piston was sitting about 2-3mm below the top of the normal stroke range. I said, "that's odd, I wonder how that could....$#@!". Flipped the motor on the stand and saw the bearing had spun. Pics are on the old phone. I'll toss them up here when i have a few.

I have my suspicions as to what caused it and I have shared my theory with others who didn't feel my thought process was correct but what the hell, I share it here.

After installing my Spec Twin disc there were several instances when starting the car where the clutch would not fully disengage the flywheel. So upon pushing the start button the starter would engage the fw spin the motor a few times and the engine would start right up and I would have to pull very hard against the shifter to pull it out of gear. Once it warmed up everything was fine.

However, there was this one instance when I was sitting on a VERY steep hill and went to start the car and the car got pulled up the hill for a good few yards since there was too much load to pull the shifter out. During this time the motor was not building oil pressure,,...add the weight of the car up hill and I think it may have been possible.

Whats different from this situation from kickstarting a car by dropping the clutch is momentum.

The motor did have 148k on it tuned since 60k so I feel I got a good ride out of it.

[zeeth2800]

The motor did have 148k on it tuned since 60k so I feel I got a good ride out of it.

We should start compiling a list of engine failures. What failed? What mileage etc...

[bigdnno98]

Interesting. Seems like I'm hearing about spun rod bearing more frequently lately. The motors are getting +100k on them now though, many are getting beat on pretty good, and others followed the ridiculous BMW 15,000 mile oil changes. None of that is good on rod bearings LOL.

[ronilrd]

I spun rod bearing number 4 replace crankshaft and install new bearings on mains and rods. I decided to build replace heat gasket. Got it resurface and clean.got new lifters and tensioner. Now Vanos gears with new bolts won't stay time to cams. A soon Ias I crank the cams stay behind like not building pressure. Car just crank.