Thursday, 21 July 2011


When I bought the 120 I was aware that the engine number W3370-8 didn't match the entry on the plate - W2142-7.  Also, it didn't have a "smooth" set of cam covers which early XK's should have.  ( the front of the cam covers did not have the normal three studs each, and tended to leak oil)  an easy "give away" that its not the original engine for an early steel 120.  What is not so easy to work out is that according to Porter, the additional studs to cure the leaking where not introduced until engine number 4691, so why has my engine, very clearly stamped W3370-8 on both block and head, at around 1,300 engines too soon, got them?

The certificate from Jaguar Heritage confirms all other numbers and I pretty well concede that I haven't got a matching numbers car.  I can just about remember that at eighteen, I couldn't have cared less.  Now at sixty three, I'll probably wake up in a cold sweat, engine and cylinder head numbers flashing through my mind, financial ruin and JDC, JEC and XK club peers whispering behind my back - never trust a man whose numbers don't match - probably has a stash of pictures of non matching numbers cars tucked away on his hard drive.

Maximum effort must be made to remedy this. The site is a wealth of information and I easily establish that W33## engines were typically fitted to 120's around June / July 1951.

Looking back through the xkdata records, I spot my original engine number!  A strangely exiting moment.  Its now ensconced in chassis number 660232, another 120 OTS with modified bodywork.  Further research  reveals that this car was auctioned by Bonhams in April.   Sold for £52,100 including commission - wouldn't even cover the cost of the initial purchase and the bits, and just think of the fitted kitchen you could have bought with that sort of money !  But it must be correct.  Bonhams would surely have checked it out thoroughly before publishing the catalogue.

Just as this intrigue is reaching its peak I receive an email from Tom at who has been following this blog, an ex Jaguar employee from many years back, with access to original XK records.  He tells me that the factory records clearly show the engine swap from W2142-7 to W3370-8.  This is really great news.  Not some mongrel old lump from an ex banger raced MK7 in my 120, but a pristine new replacement engine fitted by the works, almost certainly built and blue printed with great care by Hassan and Heynes, overseen by Baily and signed of by William Lyons himself, then road tested to at least 125 MPH by Mr Dewis.  I just need to find the signatures, no doubt secreted away on some dark and rusty panel. 

To ensure a good nights sleep, I call Anders Ditlev Clausager at Jaguar Heritage.  Anders confirms the numbers as he has access to the same records and also adds some interesting points.  It was normal in the fifties for the Jaguar works service department to re-condition broken engines taken from customers cars and re-fit them as replacement units in other cars.  So it is entirely likely that W2142 was fitted to  660232 after being removed from 660295 which then had W3370 fitted.  I wonder whose car W2226-8 originally fitted to 660232 now resides in?

My final email of the day goes to David Bentley of XK Gazette fame.  If anyone knows the new owner of 660232, then David will.  I don't particularly want W2142 back but would just like to know for sure where it is and that its being properly looked after. A bit like an ex wife I would think - or not.

ID plates, now removed from body

Engine Number
and double stamped matching number on head,
 with 11 cam cover cover  studs, not 8
I would think that the smooth head puzzle is quite simple really.  At some time after the change to 11 studs on the cam cover the head was replaced with an un-stamped head by the works, or a main dealer with access to a proper number stamp, but they weren't happy with the first hit, so did it again.