"In this new Special Series named “S85-002”, I earn a badge of honour: I blew up my V10.
I document the service history of my original S85 engine and diagnose its failure. I go through the process to source, refresh, cam and refit the replacement V10 into the E60.
In this entry, new dishes get put in. We fit the new valvetrain package, finally bolt in the Schrick cams and we go through the VANOS re-timing protocols."
Reality was bit different.
With the valvetrain disassembly completed, it was now time to tackle the re-assembly process with the new and uprated hardware. For the sake of telling a simpler story, I've split the removal, and install of the valvetrain assemblies into two entries.
The reality was different - with the heads on, you just can't do that. Each cylinder was done one at a time, removing the Genuine BMW hardware, and replacing it immediately.
The removal and install was performed intermittently. The heads on method has its own shares of disadvantages.
It was a continuous back and forth to the bench, putting old parts and pulling new parts off. Phil's order was his own here, you don't mess with someone's process unless they ask you to.
A brief intermission!
As with any project, there are unfortunately unplanned stoppages. Here, we hit a snag when realizing the Genuine BMW collets from 2006 wouldn't fit the lightweight retainers.
See the hole on the retainer? It's larger than what the first years of V10s were fitted with.
It's a small, very small different that is mission critical. Without this, the valves will all drop dead into pistons.
80x of those were ordered - 61x came from one warehouse, and 19x from another. We got lucky.
While in there, we decide to change seals. They are relatively inexpensive and easy to do. This is stepping into the refresh territory of engine work.
Seals mostly wear on Winter driven cars - which is what I do with the M5 at times. If you're seeing blue smoke, and burning more oil than you should, they might be going bad.
Unrelated to the valvetrain, I also ordered an underdrive crank pulley. I've heard about these for years from other enthusiasts, but never got around to doing it myself.
[...] 2 week laters, we were back.
With all parts received and confirmed for quantities, we trolleyed the engine from the corner back to the center of the room.
The hoses were fitted and air filled cylinder 1.
Back to playing "operations". This was the valve assembly, with the valves alone remaining, held strictly by air pressure.
Step number was dropping a brand new lower spring seat into it.
Seals are first inserted manually at the top of the valve's rod. They are slid down from this position.
Next, we slide the seal into place using this seal tool.
The new beehive springs get dropped, and the retainer is put on top. This is all remains fully supported by air pressure.
Now we get to the part that sucks. The tool kit we sourced did have a specific tool for collets - but it was crap.
Phil went all in on the "Operations" meme and used a small flat head screwdriver. The process is painstakingly long, it requires both patience and dexterity.
Step number 1 to fitting collets is to press down on the retainer to compress the springs.
Pushing it down reveals the valve's rod notches. The collets are then inserted into the conically machined hole of the retainers.
The springs are rated at 10.3 lbs per mm - doesn't sound like much, but it requires constant pressure. Over time, it wears you out, and small lapses have the collets pop out of position.
Now do this 80 times.
One by one, each collect was put into position. Phil used a slight dab of grease to help them stick to the flathead screw driver.
It wasn't a perfectly smooth process, but it did get easier per valve.
With the collets locked into the notches, the tappet was fitted and the valvetrain assembly of one cylinder was completed.
Cylinder no 1's valvetrain was now complete. Repeat this process for all other 9s.
The followers are deemed universal, still we matched them to their ports.
Sort of :)
Fast forwarding through the valvetrain re-assembly on bank 1. It was now time to fit the cams.
The Genuine BMW cams have timing marks. It's a visual reminder of the orientation the cams need to be installed.
The Schrick cams do not. This is one of many potential catastrophic errors during installation. We had matched and marked the cams to avoid this.
We fitted the correct cams, in the correct orientation, and started the cam block bolting process.
If anything was wrong with the valvetrain assemblies, this was more than likely the last time you could resolve it without another expensive bill, and time wasted.
The cam block bolt and torque process takes a while,
One by one [...]
each cam block [...]
was partially bolted down [...]
until we reached [...]
[...] the last cylinder, now do that again 3x times for the exhaust cam and start over the entire process for the intake cam. It's repetitive, high risk work.
It's about time: timing the S85.
Since releasing entries in the S85-002, I've received many messages with questions about timing the S85. All of those who reached out had further disassembled the VANOS than we did.
There's a point to be made: be very clear about why you're removing your VANOS system, and don't dismantle VANOS any further than you have to.
In this section, I'll explain how the VANOS gets timed, and how the VANOS works.
First, it starts with having the proper tools. This entire box is dedicated to VANOS timing tools.
All of them! We used everything but one.
You also need access to BMW's TIS.
The crankshaft gets locked into position.
Timing blocks get bolted to the cams. These are specific to each cylinder bank and intake / exhaust ports.
E doesn't mean exhaust. It's A for Auspuff (I think!). Read the manual.
The timing blocks also get bolted to the head.
First, we need to re-tension the intake cam gear's timing chain.
BMW M learned from the S54, and visibly improved the material of the upper timing guide. There was little sign of wear.
This cap hides the chain guide's bolt.
The bolt holds the guide, it has no other purpose. We put the guide back into proper position and bolted it on.
The chain's tensioner is adjusted using this bolt on the inner section of heads. The tensioner was also in great condition.
With the intake cam gear into position, we manually bolted the cam bolts. These are held with little torque ratings. Be mindful as they are a crucial aspect of your VANOS.
Over torquing these bolts is nightmare fuel. Be mindful, follow the instructions.
The exhaust cam gear had been bolted to the gear spacing tool all along.
It makes aligning with the cams a piece of cake.
It also eliminates any intake to exhaust cam gear aligning issues. As the intake cam gears are the only ones connected to the crankshaft with the timing chain, the exhaust camshaft is driven by the intake camshaft by the gears.
The exhaust's VANOS gearwheel is split in two. According to BMW M, this was designed to avoid gearing noises caused by a change in the driving tooth profile in connection with a change in load.
We now have our answer as to why they updated the VANOS exhaust gear. I still don't care.
If you had to dismantle the VANOS gears, or didn't use the spacing tool, you would need this tool we didn't need to attain gear alignment once more.
There are many horror stories with this. I'm glad we didn't have to get there.
Moving on, we now had to properly align the VANOS timing's range.
This tool needs to get bolted to the head, in order to align the bolts.
When timing the VANOS, it is down it's more retarded position. Here, it's indicated by the bolts on the furthest left on the slotted range.
The slotted range on the exhaust side of maximum 14.25 mm corresponds to 18.5° camshaft angle and 37° crankshaft angle. The slotted on the intake side of maximum 25.25 mm corresponds to 30° camshaft angle and 60° crankshaft angle.
Once the range is set and bolts are hand torqued, the cam bolts can be torqued to spec.
The intake and exhaust camshaft rotate in opposing directions. As such, the cam gears were designed with internal helical gearings.
In simple terms, the retraction movement is mechanically done by the camshafts themselves by pushing back on the VANOS units. It's an efficient system.
The adjustment units that manage the movement of pushing in the cams are known as the actuators. The VANOS high pressure pump supplies the actuators with oil under high pressure to perform this task.
When fully extended, the internal adjustment pistons of the actuators are subject to a system pressure of 115 bar. You can peek at the pistons at this angle.
The oil pressure itself is managed by the infamous VANOS solenoids. There are 2x solenoids per units. We installed the updated VANOS solenoids from BMW.
Phil mocked up the actuators to the cylinder head.
The mounting screws for the gear mechanism are tightened only lightly when assembling the actuators. This process is to
As a result, no force is transmitted from the outer sleeve to the inner sleeve when sliding the actuators onto the cylinder head.
With the VANOS units now fully re-assemble, we can better understand how the advance and retard motion actually works. The intake is adjusted towards advance and the exhaust towards retard when the plunger extends.
This picture shows Retarded timing position on intake and exhaust cam.
That mentally intense eh? Now do the other side!
Once more, for the purpose of fully explaining the VANOS timing and re-assembly process, I had to use pictures that won't make sense in the chronological context of the engine swap.
In reality, the cams were installed along with the VANOS gears. The actuator units were not as we needed to pull the old engine first to transfer parts over.
With S85-002 main work nearly complete, we need parts from the 001 to continue.
Up next: the E60 gets rolled in.
We remove the S85-001 and restore, replace and transfer components over, along with a few upgrades along the way.