I would see if Rob’s thinking could be carried out and have a machine shop shave a shim down to .082" or .083". As to a noticeable difference of running #1 at .002"?, the actual duration will be increased from stock and you should expect to see a slight drop in dynamic compression readings for that cylinder. The concern is if a hot engine would cause the valve gap to close up too much…the clearance spec is there for a reason.
thanks Lee, Rob, Charles: , I agree…trying to assess what is up there…and the best solution…have to check some Saab and Alfa shims as well, and would be ok to use the 004 if we can get there. Nick
I think it was Robin, but anyway I agree, a shim can be surface ground a few thousandths under .085"; the factory probably never anticipated that anyone would need to go smaller than that. You can try rubbing it on sandpaper on a flat table if you had something like a block to hold it. Maybe even do it in a lathe with a grinding stone, or on a belt sander if you make a thing to hold it square to the belt.
Ultimately it’s putting off the inevitable, you have valve seat recession and will eventually need new seats.
Please, Emery cloth, Sand paper’s for wood 
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Do you still call it “sanding” when you use emery cloth? Or is it emery paper?
Just trying to make sense of things. I do work with wood so sandpaper is what I use there.
Maddy
I said sandpaper because I figured everybody knows what it is. Sand is usually silicon dioxide or quartz or other non-metal oxides, where emery is usually aluminum dioxide or iron oxide or other metal oxides. Cloth backing is more expense but lasts longer than paper. I would try 220 emery first and see how that goes.
in any case…Maddy is working with this one clearance problem…the others are all reasonably close…just normal differences within a few thou…and normal shims. So this one position, intake #1 has an issue…that may be .006…hard to know because it seemed to have zero clearance…hoping it did allow a .0001 feeler…so that it at least had something measurable and what is needed is limited to a shim .006 thinner than the .086 that was in there…Maddy has some older shims taken out that appear to have been “emeried” which were not going to be re-used…so may as well use those to “emery”" to thin. Have at least 2 to play with…Hoping that with just one issue…the valve job can be postponed quite a while…if this works. OK…that said…anyone out there have a .080 of correct diameter on the shelf? Nick
Nick, Terry’s Jaguar Parts sells undersized shims from .075” to .084” for $4.22, plus shipping. My experience with buying shims is to purchase three - with one on each side of your target size. Invariably. the shim producer seems to measure slightly differently than I measure.
I’ve also had good luck “sanding down” shims - but only by a thou or two. I put contact cement on the shim and on the tip of my finger to hold the shim steady. Then work it back and forth on 220 emery cloth glued to a flat surface - remeasuring the shim every minute or so. It really doesn’t take very long, but if you try to sand it down too much you’ll end up with an uneven shim.
Touché I would probably call it polishing rather than sanding though.
also looking for a C7312 tappet that has the .215 deck.
Nick
While I wait for parts I dove into why the front wheels won’t turn. Brake shoes seemed an obvious choice to investigate. The left front was stuck on but got it off with minimal effort then cleaned the drum surface and adjusted the shoes to be recessed completely. The drum went back on with no binding.
The right front was a whole different story. I could not get the drum to move with a plastic mallet like the left front. I had to get the 5lb sledge and tap the drum off. When that was t working I resorted to heating the drum then worked the drum off. I adjusted the shoes to be recessed like the other side and cleaned the brake drum surface.
Maybe someone has encountered this problem before, where the shoes are recessed fully and the brake drum still won’t go on without binding. Knowing better than to hammer it back on, what needs to be done to bring the shoes away from the brake drum even more that the adjusters will allow? Is the wheel cylinder fully extended? Perhaps I need to take that apart? Examine it. The brakes haven’t been used for some 20 years, there could be multiple things to look at. Thanks.
Maddy
I’d guess the wheel cylinder is frozen in place…worth checking first.
Kinda what I figured. Can’t get to it until late this afternoon. I am curious if that is the problem.
Maddy
Still looking for the C7312 Tappet that has a .215 deck and also for that .080 shim. I will polish (sand) a shim I took out to that measure in the meantime.
Maddy
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Review earliest posts to follow this post.
I have both cams out therefore all valves are shut.
I have the engine TDC compression stroke by the marks I made on the fly wheel corresponding to the one on block.
The rotor on the distributor, if #6 cylinder was north the rotor points West with TDC compression.
I took out the retaining bolt from the distributor so I can see the off set and to know whether the distributor is set up correctly. The distributor will not turn or pull out.
While waiting for a response about the distributor I removed the radiator.
Maddy
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I interpret this to mean you took out the bolt below the distributor on the side of the lower block.
There is a clamp bolt below the distributor that has to be loosened if you just want to turn the distributor. This clamp is also held to the block by another bolt located between the distributor and the upper block.
I removed the bolt on the side. The distributor does not turn. I will look again for the other bolt.
I will look for this clamp although I have not spotted it yet. Perhaps this is why the distributor doesn’t come out.
Maddy
Bob,
I am a bit confused on what needs to be removed to get the distributor to lift out. Your picture provided a clue. Thank you for that. Let me say that the bolt in that picture is in fact removed. Is there another bolt? Should the distributor just lift out with that bolt removed, the one you have arrows pointing to in your picture?
Maddy
Here’s a photo of an original XK120 distributor clamp that I modified to make it easier to remove the distributor or to set the ignition timing.
The clamp is attached to the engine block with a 1/4 inch setscrew through the hole at the bottom of the photo. I think you can only reach this setscrew from the front of the engine with the radiator removed. Then you can lift the distributor, with clamp attached, straight up and out.
Otherwise, from the rear of the distributor, and inwards facing the engine block, is a nut on a pinch bolt to loosen the distributor clamp itself. This is the pinch bolt shown on the right side of the photo. This is a very poor original design and the reason I modified the clamp with a new outward-facing pinch bolt.
