Z1OwnersClub GB

Engine No: 115055

Clarification on valve clearance check.

With the lines on the appropriate camshaft aligned with the cly hd you can check the clearances on No's 1 & 3 or 2 & 4. So in that case the relative lobes will be in different positions, see attached, is that correct position for both to measure the clearances?

Thanks

I always measure with the lobes pointing directly away from the bucket/shim/valve. I don't really care where the sprocket marks are whilst measuring. Once the cam timing is set originally, it's set regardless of rotation.

That's why I need some clarification. The genuine manual for the Z1, A's & B's gives that precise way of checking them.

However, for the A4's and/or engine No 18866 on they give the revised procedure by aligning the marks on the individual cam sprockets such that you can do valves 1 & 3 an 2 & 4 for that cam, but in doing so the lobs are as shown, one up and one more or less flat.

If I do them with lobes pointing up the 0.10mm feeler gauges does not always pass but when done as described they do, hence some slight concern.

Measure them one at a time with the lobe pointing directly away from the shim ( 180 degrees ).
This ensures you are measuring fully on the base circle and not the quietening ramp..
Also set the clearances at 0.15mm not 0.10mm.
0.10 mm is the MINIMUM and NOT 0.05mm as stated in most manuals as this is the old figure which was revised due to instances of valve seat burning, especially on the exhausts..

Thanks