Discover what’s involved in removing the cylinder head from the famous XK engine
WORDS & PHOTOGRAPHY ROB HAWKINS
Cylinder head removal on an XK engine can turn into a nightmare of a job if its studs have corroded, so whilst the following 24 steps make it all look far too easy, there are many times when it won’t be the case.
The work involved in removing the cylinder head isn’t particularly difficult, but time can soon slip away if the fastenings for the exhaust manifold are seized for instance, or those head nuts, especially the ones around the front, are troublesome. There are also lots of fiddly components to remove and remember where they were fitted, so having an assortment of labelled storage boxes and bags helps to reduce the risk of forgetting where everything went.
Removal of the XK’s aluminium cylinder head should ideally be completed using an engine crane or a block and tackle attached to an overhead gantry, unless you remove everything that’s attached to it, including the camshafts, in which case two or more people should be able to lift it out, providing it’s not seized.
When we heard that independent Jaguar specialist, Ken Jenkins, needed to remove the cylinder head from a 3.4-litre XK engine in a Mk1, we quickly volunteered to help. We were prepared for a battle, but on this occasion, the head proved straightforward to remove.
1 Ken recommends removing the bonnet so it doesn’t obstruct when lifting the cylinder head out. After marking the position of the bonnet, four ½” bolts are undone, and it’s lifted away 2 Rob volunteers to remove the 12-volt battery in the offside rear corner of the engine bay. Its terminals are secured with ¼” Whitworth nuts, whereas a screwdriver releases the battery clamp3 The two exhaust manifolds can be removed to make it easier to lift the cylinder head out of the engine bay. Armed with a ½” socket and spanner, Rob slackens all 16 nuts securing them to the head4 The ends of the manifolds where they are secured to the downpipes are located with 9/16” nuts. They are awkward to access and undo, but eventually we can extract the two manifolds5 Mechanic Mike slackens all 11 of the 7/16” nuts locating each camshaft cover, then moves to the front of the engine to slacken five more fastenings for the breather. He intends to remove these parts 6 The breather is a little awkward to remove because the ignition coi
