Hello, all - I've browsed extensively on the site about this but have been unable to get a definitive answer. I'm reassembling the engine on my 2000 XK8 convertible after replacing the head gaskets. The engine number indicates it was manufactured in December 1999. My understanding is that the post-1999 model year engines used a slightly different VVT (mine has the type that have those truncated helical castings on the outside rather than the smooth ones) and I have been unable to determine whether it's necessary to retard the VVT during reassembly. I believe they default to the retarded position in the absence of oil pressure, but again, haven't been able to find a certain answer. Anyone have experience with this?
Thanks again for all the wisdom and advice on this site, couldn't have tackled this job without it.

 

Yes, they need to be retarded. There is a special tool in the V8 timing set to retard the later VVTs with the helical marks you mention. If you look inside the VVT hub you will see 2 holes, the VVT retard tool fits those holes.

If you look here

https://www.ebay.com/itm/40452651917...Cclp%3A4429486

The retarding tool is on the top right of image 1, you can see the 2 pegs that engage with the VVT.

 

Thanks, Hell-Cat. Was hoping I might avoid this as I have that tool and, like others have mentioned here and there, it doesn't fit without filing down the diameter. Out with the angle grinder. If I'm correct, retarding in this case means setting it clockwise

 

Agreed, it's not a good fit, I had to 'adjust' mine before it would fit in the hub.

And yes, clockwise to retard. If you turn it counter clockwise it should spring back. If it sticks you might want to consider a good cleaning before you install it after all of the work that you have invested.

Good Luck !