S50 vanos install +cam setup

[DJ1904M3]

Hi all,

Just a question to see if I have made a big boo boo.

I am (was) mostly though my cam install and vanos refit, but . .

When installing the vanos and fitting up the camshaft hubs, I didn’t torque the intake cam enough and when I rotated the engine by hand, the intake cam “spun” on the hub until it locked out on the hub assembly.

Now, my question, was this movement in cam timing enough to cause me to have hit intake valves on the pistons during hand rotation?

 

[MParallel]

If I understand you correctly....as long as the hub is still in place the hub 'endpoints' (the movement in the slots) should be within the safe limits.

You should still be able to turn over the engine.

 

[DJ1904M3]

If I understand you correctly....as long as the hub is still in place the hub 'endpoints' (the movement in the slots) should be within the safe limits.

You should still be able to turn over the engine.

Thanks for the reply - I think you deciphered my panicked jibberish.

The intake hub was assembled, 2x m8 bolts were securing it ( just not enough to stop the bolts sliding all the way to the end of the “slots”) so when I hand cranked, it all moved .


I added a picture -

In the top picture that is the amount of “movement “ in the hub circled in blue.

The bottom pic was the hub assembled- how I had it (just not tight enough)

Hoping that “that amount of movement “ was within safe limits !!!

 

[MParallel]

When you retime engine/change cams and you install the hubs, you always start with the bolts not clamping, as you need to rotate the hub to insert the splined shafts.

If vanos was already fitted and it slid afterwards, you have to take it off and start with the hub in their 'starting position'.

Of course all this with the presumption that engine was at TDC and camlobes on cylinder 1 poiting upwards to each other.

 

[DJ1904M3]

Thank you for the reply.
Yes, engine was at tdc, and cams were set up correctly (alignment tool used and notch to bearing cap)
Vanos was not fitted as I was just checking rotation .

But I am only worried that I hit the valves due to the slippage on the intake cam hub and the change in that “tolerance/timing”

Hoping that would not be the case

 

[Iain]

highly unlikely, also unless your hanging off it you wont bend the valve, its a steel rod so takes a good bit of force to do it.

 

[DJ1904M3]

I’m hopping that’s the case , I will do a leak down test on Saturday - just to be sure.

But I’m hoping that then the amount of “slippage” in the came wheel does have a margin of safety built in

 

[MParallel]

Well there is. The slots are the safety margin.

 

[DJ1904M3]

Just a bit of an update , I did a leak down test on the motor and had ~20% on all cylinders. Except with number 3, it was about 26. There was air coming past the valves on all cylinders, but more on number 3. I put some liquid in the port and it was bubbling - is this normal or should the valves be “air tight” ?

 

[DJ1904M3]

Spoke to the guy that reconditioned the head - he said no air should pass the closed valves.

And that there is a very high chance I have bent all 12 intake valves by doing a “hand rotation” with the cam timing out by the amount in the “hub sliders”

So does this Mean , I pull the head off again and need to get it tested /checked

 

[MParallel]

If you go by what Ian wrote and he knows his stuff, I don't see you having bent all 12 intake valves. They don't even open at once, so you must have brute force bent one pair, then another one and then yet one more after that.

Can't you use an endoscope if you want to be sure?