valve tappet adjustment

No, the seats were installed in an earlier stage before the head left the machine shop.

George, William,
As the recommended interferrence fit is the same, or at least it is now. do you think the valve seats were installed at the same time as the tappet guides?

That would be an interesting picture to post, those roasted tatties were delicious!

William --spot on! I have a great picture of a worker at Browns Lane in front of an oven where 6 or so heads are being heated for inserts---best part is if you look carefully you can see several potatos being baked at the same time! Wonder if the potatos caused the lift in early cars--must be b/c I have not experienced that except in cases of exterme overheat!

Some interesting comments here, George, would Bob have been correct calling them "downers"? or, do they still lift the valve off it's seat? And Bob, "you will save some leaves for him" you mean if you didn't save any they would all be gone? As for the sleeve problem, I can't recall if we have ever had one come loose in an E type, although it could happen to them if the conditions were severe enough (overheating. The problem was caused by a change of assembly procedures about the time I was working at Browns lane around 1974/5. Hitherto, heads were heated and sleeves were frozen then assembled with a .001 interference fit. In order to increase efficiency -as was the focus under British leyland Stewardship (Michael Edwards)- the sleeves were pressed in at room temperature with a .002 interference fit. This worked fine unless the head got very hot. The factory always denied there was an engineering problem then, two years later, provided a repair kit to rectify it! Anyway Chuck, I'm assuming you got the message to have the noise diagnosed.

Just because it is an early engine such as in a XKE does not preclude the tappets coming loose. We see them all the time. Of course, 9 out 10 occur in the later emission engines. It is for this reason that both inlet and exhaust tappets are locked down in all of our heads. As far as the current noise in the engine, any sudden onset of an unusual noise should be checked immediately. Ignoring problems on a Jaguar cost more the longer they are ignored as a general rule.

You are right that any guide problems occured on the later cars. but the point that I was trying to make was that if the engine suddenly developed a racket it would be best to check in to it. I do know what you mean by set wide etc as I haven't run a stock set of cams in a number of years and while the valves may be a bit noisy they all sound the same.
If you feel like raking some leaves I'll save some for you!

Oh Bob you know I love you like a brother but dang it ain't a lifter guide in that engine--all those hold down kits are snake oil for anything per cat converter--set them wide and enjoy the noise LOL --hey didn't Jaguar run hose cars for 24 hours somewhere with out kits?

It is unlikely to be a valve adjustment problem as, on these cars, they get quieter when they bed in, not noisier! It is also unlikely to be a slipped guide as this was only a problem from around 1974 engines, But any noise is worth checking.

Chuck, If the noise just suddenly appeared, and especially if it's on the exhaust side, I'd have it looked at like right now as there is a possibility that a valve lifter guide has drifted up.