Lifter Noise on Startup

[81stubee]

Hi Folks,

Finally trying to fix the lifter noise i've had since the new motor 50,00km ago. I've removed the manifolds, valley cover and one of the rocker assemblies.

Inspection of the underside of the arms reveals some pitting in the socket part of the inlet rocker for number 6. See attached photo.

https://www.dropbox.com/s/uyd9hexbc8hdk7h/2014-03-18%2012.03.58%20%28Medium%29.jpg

Does this look okay? But that said i cant see how this would cause a rattle for 5 seconds at startup. Any other suggestions?

Stu

[PhilipA]

Seeing that you have had it since fitting the engine, IMHO it is most likely to be insufficient preload on the cam followers. This could be from rocker wear of rocker shaft wear. Were they replaced with the new engine?
Regards Philip A

[81stubee]

That's the lines that i was thinking, i'm not sure that they were replaced, but they do seem in reasonable condition, but it only sounds like one lifter. Plus, further inspection has idetified a few things:

- Several Lifters appear to be dished, i would of though that 40,000kms wouldn't be enough to do that.

- I appear to be only getting 7.2mm of valve lift. (Measured with a Vernier on the top of the valve stem.

[81stubee]

Ignore my last, had a blonde moment!! The lifter was compressing causing me to get such a small amount of lift at the valve stem.

New Calculations:

Actual Lift from the Cam is 0.270" = 6.85mm

Rocker Ratio is 1.6

Therefore = 1.6 X 6.85mm = 10.96mm

Which to me, says that the theoretical lift of the Valve is 10.96mm.

I was merely checking this to confirm that the correct camshaft had been installed, which is meant to be a PC216.

I'm going to check the preload tomorrow.