Whats the trick to removing the cam so I can change shims on the exhaust side only? Where do you guys get your shims?

 

To clarify, I have two tappets touching the cam when the lobe is off the tappet. So two of the guides I assume have moved up. My loud knocking is audible under the cam cover in about the same areas as the two tappets that have no clearance. I was trying to knock down the guides and using my feeler gauge to see if they moved down at all. My new plan is to try re shimming to get my cold clearances and install the stake down kit. After all this work the last couple months, I have the car starting and running very well and it's killing me to not be able to drive this absolutely gorgeous designed automobile.

 

Forget the "its pretty and I want to drive it" unless you want big mechanical problems/expenses.

Changing shims under the buckets is not a job easily done by a newbie with this style of DOHC. It takes some patience and accuracy when removing the cam and selecting the shims to use (they are marked with a letter if I remember right (I gave up on this type of engine long ago), if you look closely at them). You must measure each cam to bucket with the cam base at its lowest location (valve closed). Tedious stuff - do not get lost.

I would establish what position the cam is in and measure the clearance (cam to bucket surface) and then mark it down on a piece of paper in an organized manner. Do so for each lobe of the respective cam. Double check when establishing this baseline measurement. Then select /install the thickness of shim to install that will yield the proper clearance

You will have to remove the cam or at least lift it up to get access to the shim under the bucket where it shim lives. No sure if you can get access to the front shims in this manner - you may have to remove the cam completely.

You will have to remove the cam bearing caps and maybe the cam gear (keep it attached to the front upper chain or you will be in a world of hurt - as you may lose the cam timing relative to the other cam and when the valves collide upon rotation of the cam (s) $$$$$$.

So research this until you have a firm grasp on what you are trying to do or you will find it can get very expensive and as a result, no driving the pretty car for a while. This is serious stuff that even the most experienced mechanic will slow down and pay attention to. No interruptions / disturbance are required once you start the process - its easy to get lost and screw things up. Keep the paper with the old and new numbers handy....checking clearances frequently. Too tight a (lack of clearance) and you will burn a valve (head removal / new valves)...too loose and the noise will drive you mad.

 

There's no trick. Not sure how much detail you're after. Do you have a shop manual?

In simple nutshell you simply unbolt the cam from the cam gear and remove the cam camshaft bearing caps and lift the camshaft away. Let us know what you're uncertain about and we'll help clarify

This shows the fundamentals although your later model 4.2 engine has four cam bolts (not two) and locking tabs (not locking wire)...and lacks the tach drive mechanism

Valve Adjustment on a Jaguar XK Engine Austin Motor Scene

You'll want a cam alignment tool like this:

Welsh Enterprises, Inc - Jaguar Tools Parts - Cam Alignment Timing Tool

Order shims (after determining the sizes you'll need) from a Jag supplier.


Cheers
DD

 

I ordered a genuine Jaguar service manual but it has not come in yet. As for the cam and shim stuff, the design is the same as my vintage metric motorcycles I rebuild/restore. That tip about lifting the cam is exactly what I wanted to hear.

 

I removed the cam caps and placed them on a tray in correct order. The cam lifted up high enough for me to remove one of the zero clearance tappets and shim. On my caliper it measures .100 I will go Friday to my local Jaguar dealership and see if I can purchase a .088 and see how close it gets me. The other one that the guide has moved on is at the front and can't get it out unless cam comes out. It got dark outside so will continue tomorrow after work. Just my luck one is at the front. Lol. Hopefully the dealership parts department has these in stock. Heck, I bet some of the older mechanics probably have some in their tool boxes.