Friggin Vanos Exhaust Hub

[StickMon]

Opened her up to do a routine valve adjustment this morning, and guess what I find, sticking its tongue out at me.
One tab broken. Typical 1/2 moon crack. Piece miraculously still flopping around in the oil pump hole.

After the panic subsided, and I started to formulate a plan, jumped on Dr. Vanos website and ordered a c300 hub for next day delivery.
Waited a couple minutes for PayPal to go through, then placed a follow-up call to the Dr.

Chris had already left the shop for the day, but it forwarded to his cell phone.
He agreed to go back to the shop, pack one up, and drop it at UPS for next-day air, Saturday delivery.

Now that's service!!!

I have a feeling the yard work won't get done this weekend.

[mtrhed]

Ouch! Sorry to hear, but good that it was caught before the tab migrated. Is the c300 hub the one TurboToy on the M3 forum came up with? I'm getting close to valve adjustment time and am thinking of having everything on hand before I begin! Take some pics if you're DIY'ing it.

Good Luck!

[StickMon]

Yes, it's the TurboToy hub.
Good idea to buy one ahead of time. I think we'll all need one sooner or later.
I really baby the car. Hardly ever over 5500 rpm DD, and still it broke.

Here's the current state of things. Finished the valve adjustment.
Have the crank pinned at #1 tdc. Alignment pin in intake camshaft.
Exhaust camshaft is fully advanced (starting position) and won't budge.
I tried and failed to turn it once before, so no surprise there.
But now I have the switch box and air coupling.
As soon as I get the new hub in my hands, I'll hook those up and hopefully will be able to get it to turn.

If my Son's around tomorrow, I'll have him get some pics.
As you can see my phone takes lousy pics, or maybe it's just me.

[mtrhed]

Wow! Way to attack it! Were you able to get the Vanos tools from a dealer? Never done this, but like you said I think we'll all have to deal with it sometime. I like the "get over the shock, form a plan, and go for it" mentality!

[StickMon]

I've been collecting Vanos tools for over a year.
This thread by beta got me started.
Built my own switch box. See post 20 for bignosejim's solution to the air coupling.

I knew it would eventually come to this. Either for the hub or seal rebuild.

[mtrhed]

I got ya. Think I'll start prepping for this myself.......

[bignosejim]

So sorry to hear this happen One other thing you should do is check your upper chain tensioner guide. On M3Forums a few have been wearing down on the underside.

Here's a parts diagram. It's #3.

Here's a post from M3f showing the broken part. There are a few more if you search.

Hope you get it all sorted and back to normal soon. Definitely let us know how all the tools work out for you.

[StickMon]

Got the Vanos off.
The air line and switch box were no miracle cure. Still couldn't budge the exhaust camshaft.
Put the 60mm bolts in the Vanos top holes, took the other 3 bolts out.
Yanked the exhaust camshaft a little in the retard position, and got about a 1/10 inch gap on the exhaust side. Enough to retrieve the broken tab.
Pulled on the intake side, and it started to come away.
Went back and forth using the hex on the exhaust camshaft to walk that side, then just pulling on the intake side until I had the couplings exposed.

Here's the tricky bit to getting the Vanos out of a Z4.
No need to lift the engine. No need to remove the nose of the car.
The thing that prevents you from weaseling it out is the Control Valve.
Holding the Vanos in one hand, you have to remove the control valve with the other, before you can get the whole thing to come out.

Put a shop rag in the timing chain area first !!!
The Control Valve is oily. It slipped out of my hand and almost went down the rabbit hole.

[bignosejim]

Congratulations on getting the vanos out of the car. Glad you didn't drop anything into the engine either!!

Now all you have to do is put everything back together...

[StickMon]

Vanos is back on. Exhaust side is a PITA.
Not enough travel in the Vanos exhaust piston to jam it all the way home.
Of course, camshaft doesn't want to turn and draw the spline pin in.
It likes to turn in the direction of pushing it out, though.
Finally used a screwdriver to push on the face of the spline. Moves about 1/10 inch.
Then wail on the camshaft. Moves about 1°.
Lather, rinse, repeat until the Vanos is in position.

Exhaust camshaft is still massively retarded from the normal starting position.
Exhaust Vanos piston is pretty much bottomed out.

Should make some interesting noises when I start it.

[bignosejim]

Did you try to use the switching tool to ventilate the pistons while pushing in the vanos? Sounds like it won't be in proper time when it all goes back together. Did you have a chance to look at your timing chain guide while you were in there?

[StickMon]

it's alive

ALIVE

Update when I recover. Need food.

Need beer.

[dubsesd]

Lol. Job well done

[StickMon]

Originally Posted by bignosejim

Did you try to use the switching tool to ventilate the pistons while pushing in the vanos? Sounds like it won't be in proper time when it all goes back together. Did you have a chance to look at your timing chain guide while you were in there?

The air line and switches are great for venting the oil, all over the place.
As expected, the 80 psig I was running isn't enough to get the camshafts flopping back and forth.
It did come in handy to re-extend the pistons after I reinstalled the Vanos with the pistons fully retracted.
Pistons were moving freely after venting. You just don't have enough leverage to get the spline to pull in. It would have been a good idea, after setting the timing but before putting the Vanos in, to push the exhaust spline in until there's just enough "dihedron" sticking out to be able to connect it. I think it would have been far enough in that the Vanos could seat without bottoming the exhaust piston.

The Control Valve is less of a hassle on reassembly. Just stick it in the head before putting the Vanos on the 60mm bolts.
So I guess the right way to get the Vanos off would have been to make sure the Control Valve stays with the head, not with the Vanos.

I tried to get a look at the timing chain guided, but the bit that I think breaks is farther down than I was able to see.

[StickMon]

I knew from INPA that both camshafts were within 2° of nominal before I started this adventure.

Pinned the crank at #1 tdc. Jammed some junk between the locking pin and the frame so that it couldn't fall out while I was wailin' on camshafts.

With the "bridge" over the head, the intake locating pin pretty much falls right in. Bumped the intake camshaft at the hex just a little to get the pin to drop clean through.

As stated above, had to unbolt the Vanos to rotate the exhaust camshaft.
Maybe some more blowing and switching would have freed it up, but it worked out. Walked the Vanos out to a convenient distance to get at the coupling, and got the exhaust camshaft to line up with the locating pin.

So with it still properly timed and everything pinned through the reference holes, the distance from the face of each hub to the face of each spline pin is about 1/4". As many M3 DIYs say, you can just see the spline teeth peeking out.

The TurboToy/Dr. Vanos c300 hub is 1/8" longer than stock, so it needs to be put back together with the spline sticking out 1/8". (Not the teeth. End of hub to face of spline pin.)

Put the new hub on with 2 bolts finger tight. Rotate full CW (as viewed looking at the front of the car). Insert the spline and slowly turn the hub CCW until the first set of teeth catches. Continue CCW until the spline is sticking out 1/8" and tighten the bolts down.

Well, almost. After you compress the cup spring you end up with too much sticking out. So it's try again until you get it to be sticking out 1/8" after the cup spring is compressed. Then put the other 4 bolts in and torque all 6.

This is where you should unpin the exhaust camshaft and try to turn it in the advance direction while pushing on the spline pin.

[bignosejim]

Good job to get this done in one day. Have you had a chance to run a vanos test in inpa/dis to see where everything has settled out?

[StickMon]

Drum roll please

3.0° advanced from nominal. I'll take it!
(Sollwert = commanded)

[mtrhed]

Well Done

I resoldered the Vanos solenoids on my e39 M5 and I have replaced the filter and sealing plate/o-rings on this car but I have not removed a Vanos unit yet. Gonna start studying up on the procedure. I believe I will get a TurboToy hub, Beisien seals/rebuild kit, intake hub bolts(TurboToy), and upper timing chain guide and maybe a new timing chain tensioner and do it all at once, proactively.

Nice to have some tricks that are Z4M specific.

[inTgr8r]

Nice work!!!!!!

[StickMon]

Originally Posted by bignosejim

Good job to get this done in one day. ...

I have to give Chris a.k.a. Dr. Vanos a lot of credit for making this possible.
I'll be buying a rebuilt from him in 6 months or so, if mine holds out that long.
Was thinking about doing the Beisan rebuild, but decided I'm willing to pay the Dr. instead.

[StickMon]

My Son snapped a few pics. Sorry, not enough for a proper DIY, but I was still in stress mode.
Didn't know enough of what I was doing for a proper DIY anyway.

Oil pump face is a little toe-up. It will have to do until I get a rebuilt Vanos.
The damage is right near the edge, and the pins on the new hub go deep, so plenty left to bite on.



Here's everything pinned in the reference position.
Note the wood shims and plastic putty knife keeping the crankshaft locking pin from falling out.



Here's what the intake spline looks like. This is 1.3° retarded.



Here's what the exhaust spline looks like with a stock hub.
Not sure exactly what the timing was in this pic, but I'll guess about 4° retarded.
Something less than the 8.9° retarded that it was when I started.
You can see by the Sharpie marks that I was adjusting it when I saw the broken tab.
Anything within ±10° is easily in range of the adaptation.
I was planning to do a little fine tuning as long as I was in there for the valve adjustment.
Then it all went pear shaped.



Make sure to get this shop rag in the timing chain hole before extracting the Vanos.
I think I'm having some PTSD over almost dropping the Control Valve in there.



Old and new hubs.



New hub installed and timed. This amount of spline protrusion came out to 3.0° advanced.
Before I replace my Vanos I'll see if I can buy a depth mic and get more exact measurements.
I didn't even have my 6" machinist's scale. Left it at work.




And here's my Chief Photographer and future Rocket Scientist.

[bignosejim]

Did you end up using all of the tools from the TIS guide (or "similiar")? Did you use the hook wrench, spanner wrench and spacer?