Jaguar Repair: valves, cam sprockets, dial caliper

Question
QUESTION: pulled head and had valves done. put back together shim and  tappets back same order came out. now got no compression.

ANSWER: David,
You can't use the same shims if you did any valve work, because the thickness of the shims (pads) are how you adjust the valve clearance. Any work on the valves requires that you change each pad (shim) to what ever gets you the correct valve clearance. You need a micrometer or a good dial caliper and an assortment of pads. Available from Jaguar.
If you are not familiar with the procedure let me know and I will go over it for you.
Howard

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QUESTION: yes i would be very grateful if you would go over the procedure for me

Answer
Check valve clearance and write down what you get on each valve. Then remove the cam covers and turn the engine over until the notch in each cam on the forward edge of on number one cam bearing is pointed in toward the combustion chamber and stuff a shop rag into the forward edge of each cam sprocket and unlock the tab on the head of two bolts that hold the cam sprockets on to each cam and remove two bolts from each sprocket. (the reason for the rag is so you can not drop a bolt down into the front cam cover) Remove the rags and then rotate the engine until both notches are at EXACTLY 90 degrees to the surface of the cam covers. This will give you access to the other two bolts on each cam sprocket. Stuff the rags back in and remove the other two bolts on each cam. Then you can remove the cam bearing caps and remove both cams. Now rotate the engine so as to get # 1 & # 6 off of TDC just a little so you don't have a danger of pushing a valve into a piston. Mike each shim (pad) and write it down as to which valve it was on. Compare the clearance you wrote down at first with the thickness of it's respective pad and change to the correct size pad to give you the correct valve clearance as per your specs called for. Now ONLY install one cam and rotate the cam checking the clearance on each valve to see if you measured correctly. If it is still off, write down the new clearance again and remove the one cam again and change to the appropriate pad to give you the correct clearance. Install the cam again and recheck. If it is correct this time remove that cam and do the other the same way. YOU CAN NOT HAVE BOTH CAMS IN AT ONE TIME WHILE YOU ARE DOING THIS!!!!!! If it takes a third removal on the first cam then that is what you have to do. When you are sure every valve clearance is correct then and ONLY then can you remove that cam and do the other.
When the second cam is done. YOU MUST RESET THE CRANK BACK TO TDC EXACTLY ON #1 & #6. then you can install both cams at one time. Don't forget to stuff the rag in before you attempt to put the two bolts with their lock tabs in the sprockets. Sometimes it is necessary to pry the sprockets onto the cam flange especially if the upper chain tensioner is tight. If the chain tensioner is too tight you may have to remove the breather cover and loosen the chain tensioner a little to get the sprockets back up on the cams. (You can just snug the bolts down and not lock the tabs yet. When both sprockets on with two bolts in each you can now rotate the engine to gain access to the other two bolt holes. When you get these two in, torque them down and lock the tabs and then rotate the engine to regain access to the other two and torque them and lock the tabs on them.

If you had rotated one cam while both cams were installed when you built the head you probably bent several valves and you are wasting your time trying to adjust them. Another way to bend a valve when building a head is to lay the head on a flat surface like a bench while the valves and cams are installed as the weight of the head will bend a valve on the bench.
Howard