Needless to say this is completely backwards. Once you’ve got it on tdc you adjust your distributor to break point, with the dist positioned so the wire to no 6 is over where the dist rotor is pointing - rotate the distributor whatever direction you have to to achieve this. Static timing is not accurate enough for final tuning. Then you time it with a light, and adjust. Your car will run at 20 degrees BTDC, and probably run reasonably well, thou it will be difficult to start. If you have a problem with unsteadiness on the timing mark you have a problem with your distributor - typically wear.
Did you disconnect the vacuum while checking timing at idle.
Where’s Joey staying you need to replace with a 123? 
Although that is now the thing I would, and did do.
Hey Skene, I am a novice when it comes to these Jag engines, but I have some observations from my own engine currently in process where I removed the crank damper. BTW, for many years I lived south of Warner Rd!
On your rough tooling, there is nothing at all wrong with what you have made. But there is an easy tool you can make. Take two sparkplugs and hollow them out. Take a bolt and round the head to make a smooth cap to contact the piston top. The “sparkplug” holds alignment very well and the “bolt” can be used as a piston height detector, a piston stop (with a nut on it) and I use it to use a dial indicator if you need good accuracy. Looks like this:
Should you decide to remove your damper, during the damper removal, the main large bolt is RH threads as has been mentioned: righty tighty, lefty loosey. The pulley is supposed to come off the actual damper when you undo the damper from the crankshaft. In my case it did not; my damper was firmly seized to the damper with paint. A caution here with the damper removal, do not pry the damper nor the damper pulley off with a screwdriver and pry bar. Rather remove the damper by a nondestructive means such as a pulley puller. That’s what I did. I left the pulley in place and removed it later on the bench. Prying the pulley off may break it…as mine was broken by some PO. See pic.
The following pics may be of value to you as they show the cone in place on the crank, etc.
Your damper will have a number machined on the rear face that will identify it and on the front face it will have the stamped word, “comp.” That does mean competition, but from years before there was an E-type in the line-up of Jag models. All 6-cyl E-types have that word. (You experts correct me if necessary as I know little about the 4.2 engine.)
Thanks again for the info, always good here. Yes as you can tell I am a bit of a novice with the timing. I forgot to disconnect the vacuum advance when I was running it with the timing light. Oops, that might explain some of the dancing. So I will need to check that again. And I had my strings crossed with the points. Scott I am off Chandler Blvd so not far from Warner (great pics). I never see another kitty on the road here, just mine sadly.
1 Like
Skene you don’t need to set the car exactly at TDC for timing, using a dowel and watching it move up and down is accurate enough. Make sure #6 is on the compression stroke by looking into the oil filler hole at the can lobe forward of the hole. It should be flopped over to the left. If not, you are not on the compression stroke. This is the first step. Then manually turn the dist until the #6 wire is directly over the rotor tip. Start the car and turn the dist to a clean idle - then time it with your light.
I checked the new mark I made using #6 TDC reference with my fancy dowels after previously running the car and it was repeatable at the sump pointer. So with that I did the timing check. Static timing I mentioned previously appeared to show a significant advance on the order of 22-25deg. Dynamically it also shows about the same according to the timing light (had operator error in the previous post). So it appears mine is ~2X advanced per the SM recommendation. My idle is a little rough, but it does run strong. I do believe there is some pinging under a load when it is hot. My thought is to retard it ~5degrees and see how it runs and go from there. Seems a bit advanced, but I know the cams were modified previously and the car has a history of drag racing. So perhaps some tuning was done to it.
You’re losing me here. What is a “SM recommendation”? Jaguar recommends 10 degrees before TDC . You can run the car at 20 degrees BTDC, but it will potentially generate the problems you have described, plus it can make starting really difficult.
Service Manual?..
“So it appears mine is ~2X advanced per the SM recommendation”
That makes sense. Skene is saying it’s currently set at 20 BTDC which is 2 X what the S.M. recommends. (10 BTDC)
Have you confirmed that your mechanical advance is working (not stuck at 22-25*)?
A quick check is to flip the rotor and see if it moves and then smartly snaps back.
Yes Service Manual. I work in the land of acronyms and was a little lazy on the typing. I have not checked the centrifugal advance in the distributor (good point thanks). I hope to do some more fiddling tomorrow.
It took a few days to get the fiddling time and rolled the dice at bit with this one. I loosened the dist pinch bolt and noticed the dist would easily rotate CW which is not what I wanted. It was restricted going CCW. The goal here was to retard the timing a bit. So I gave it a nudge CCW. I started it up, warmed it up and checked the timing. Well the nudge was enough, timing is now at 12deg BTDC (using my new mark…it was ~22deg previously). With the timing change the idle dropped about 200 rpm and was a little rough so back to the carbs. I leaned out the mixture from 3.5T to 2.5T on all three which helped, going more rich was worse (still has some splash, but better). Took it for a spin and it ran well with no pinging. The odd part here is why the dist would only rotate in the one direction more than the other. This did not seem normal to me, but I have no reference for this since this is the first time I have done this on the jag. Again I do appreciate all the useful info I have received here.
There’s the bolt to the block which allows some travel and there’s the pinch bolt which clamps the shaft and in the process produces a ridge that will be in the way of free turning, nothing wrong with it, you might want to try advancing the distributor little by little again until you just get some pinging under high load and then back it back off a hair.