CAS Doesn't Fit in Head

[aves911]

I am reassembling the car after replacing the head. On the new head, when I am trying to install the CAS, it won't fit.

I cleaned out the hole in the head, but it seems that the CAS is too larger or the hole too small. I tried gently helping the sensor in with a rubber mallet and slightly scored the inside of the end cam journal.

This makes me think someting weird is going on. On my old head the CAS will slide in and out with little resistence.

Has anyone ran into this problem before? Any ideas or suggestions, as this is my first head install, I really don't know how to proceed. Any help is much appreciated.

Thanks,
-Jacob

 

[Defiant]

What year is your replacement head?

 

[aves911]

I'm not sure of the exact year, but it is a 1g head same as the one I took off, the sensor is an older green top model.

-Jacob