Left over grub screw!

Please can anyone identify the screw in the photo below.
I am just rebuilding the 4.2 series 2 XJ6 engine in my car.
It was found amongst the parts for the cam chain - but clearly it’s not from there.
It’s a 3/8 UNF and looks like a grub screw but could be a plug (from the crankcase?)
All a bit worrying.

Thanks in advance for your help.

Pull off your oil filter housing. It plugs the drilling to the main bearing behind, pretty sure that’s it.

Welcome by the way!

I just looked that up in the parts book with no luck. I remember it there…it’s the only grubscrew because it needs to be flush, where the other’s don’t. But wouldn’t it be 1/2 inch UNF (20 tpi) like the drillings at the other mains, not 3/8 inch UNF as this bit is said to be?

Hm may be. Then again the only other grub screw is plugging the oil bore at the front, right? Worth checking.

Behind the motor mount? I looked up C15867 and it’s a lot shorter relative to width than this one. I never took it out so I don’t know first hand. Not sure why it has to be so short, either. I suppose we’re a bit off topic? :slight_smile:

Thanks David and Robert,
David, thank you for your wlecome and I’m sure your right, but the one behind the oil filter is present.
Anyway, I have found where it goes - on the back of the timing chain inter-mediate shaft (hence, being with the stuff for the timing chains) see photo.

C2305 is on the same axis as the crankshaft and plugs the long main bore. That is a lot bigger though. The C&G part seems to be much shallower but I guess it does the trick and it doesn’t have to be leak proof either…

But I see it’s not that anyways. Happy you found it! I guess mine has one there too, should know as I dismantled a few months ago but oh well.