Hi All,
I am currently in the process of doing a valve adjustment on my 69 XKE 2+2. Its the first time I have been this deep into an engine, as my confidence was high after rebuilding my Stromberg carbs. I measured the existing gaps with have now removed the camshafts and measured the shims. I think I am about ready to start ordering new shims and swapping existing shims where possible. I created the following spreadsheet to try and track everything. As I grew up in England during the decimal age, its a bit strange working in thousandth of an inch so wanted to post the numbers and make sure they make sense before starting to order new shim.
I have new Cometic gaskets for the valve covers but wanted to also check if anything else needs replacing while I am in there such as the rubber seals at the end of the camshafts. The camshaft and bearings all look good to me so was just planning on putting everything back as it was. Any input appreciated.
Get the rubber parts, some sealant might be good (just for the sharp corners back there!)
And do consider stakedown kits if you don’t have them yet.
Be prepared to take things back apart again after completion and subsequent measurements… and I assume you have safety wire for the cam sprockets, if you have that.
Be careful nothing falls into the timing chain area…don’t ask.
But also if you reuse shims the centers are generally worn down more than the outsides (obviously) so just be careful with your measurements. You can also “grind” down the shims by sliding them over some 400-600 grit wet and dry sandpaper if you want some very fine tuning.
Also check around to see if anyone / club has a box of shims. We had one floating around here that everyone used and pitched in new/old shims.
Maybe you have these but best to use the proper tools: cam setting gauge to ensure both cams sit 90degs to cam cover surface; and the top chain tensioning tool. Also how long has it been since anyone had a look at the lower tensioner - a “while you’re in there job”? Just to make sure you don’t have too much travel - others have done this with a USB camera if memory serves. Paul
There is a school of thought that the safety wire isn’t its namesake and can become a problem as they have been known to, albeit not very often I would suspect, come undone. A veritable “Spaniard in the works” as John Lennon would have put it. Not unlike the stupid little tag on the chord of a halogen work lamp I bought that warned about keeping stuff off the lens for fire concerns. I was using the lamp and then I smelled something burning.
Some good information here. I do have the cam gauge and timing chain adjuster tool and used them to get everything in order before removing the cams. I have a big oil leak also so plan to remove the oil pan and replace the gaskets. If I have the cam covers off and will be removing the oil pan, is that a good time to change the timing chain cover gasket and see what lurking behind. Or is that something I don’t want to get into ?
I did not consider sanding the shims as I thought they would have a hardened surface which should not be removed. Sounds like this is not an issue and as most of my exhaust shims are over by 0.001 I should be able to do it on these. In fact I should be able to do that for most of the shims. The only ones that are a ways off are Inlet #2 and Exhaust #4 but looks like I can swap these and only be 0.001 undersize. So think I will try that first and order new shims if needed after refitting and checking the gaps again.
I have updated my spreadsheet with the information for moving shims so I don’t get too confused.
I wouldn’t remove the timing cover unless there is something specific you need to look into. With the head still in place, it seems to me that there is more of an opportunity to cause problems than benefit to be gained by taking a look to “see what’s lurking behind” unless you suspect a problem there. The timing cover can be removed and replaced with the head in place, but it’s not trivial. I had to do this on my engine to recover a stud that was dropped into the timing chest by some butterfingers(!), and in doing so tore the thin section of the head gasket around the top of the timing cover. I’ve failed to seal the resulting oil leak despite many attempts. If you end up having to remove the head, then you’ll have the worry of snapping one of the head studs which can become corroded in the '69 and later engines…
I use a spreadsheet too. Saves head scratching. Correction. Saves some head scratching. “Some” because you will measure things as accurately as you can, put in what should be the right shims according to the simple math, reinstall the cams etc., remeasure the gaps and, as David says above, find some are still not bang on. It’s why having access to a box of community shims, per Michael’s point, is so helpful.
Here’s a screenshot of the spreadsheet I put together years ago - still works:
I posted a link to it (the file extension to which needs to be changed to .xls before it will work to satisfy the security provisions of the J-L site software) here:
Well I got it all back together this weekend. Using the existing shims I managed to move them all around and with a little sanding and a few cycles have them pretty close. Worst one is 0.001" out so I think that is good enough for now. I have a feeling the cam caps were not torqued down properly as after refitting on the first attempt, the gaps were smaller that I originally measured.
A couple of things I noted while I was in there.
One of the cam caps was orientated incorrectly. I decided to leave it the same orientation in case the wear was different if I corrected it.
At TDC #6 and #1, the timing pointer is pointing at 6 degrees after, looking at the straight side of the pointer. The angled side is close to 0 degrees. Can I move this or should I just use the angled side of the pointer.
Now on to the bad news. It all back together but I cannot get the car to start. I checked I have spark at the plugs, it looks like there is fuel at the carbs and I have compression so I am not too sure what going on. I am going to backtrack and check everything again but I am stumped as to why it will not start. I have a new battery so it turns over fine but does not seem to fire. The cams are removed and maybe the chain is slightly tighter but that should not affect timing as the sprockets were connected to the chain at all times at #6 TDC (cam cutouts checked with tool). Only other things I did was remove the coil for access to the timing chain tensioner but I took a photo and connected it back the same. I do see spark at the plugs. Also, I soaked the spark plugs in kerosene to clean them up a bit. Could that affect anything ?
I can’t imagine soaking the plugs in oil (even thin oil) is a good thing. I use a pneumatic plug cleaner (uses an abrasive) followed by blasting them clean with an air gun:
I removed the distributor cap so i could see when approaching TDC #6 but did not remove the leads, and cap can only be orientated one way. I will get some new spark plugs tonight to remove that doubt.
I agree with Geo. Plugs are cheap and not made to be soaked in fluids. You more than likely need a new set.
I could tell you a story about a 16 year old with his first car who thought plugs could be washed in the dish washer, but I won’t because I’d have to name names.
My offset cam was fused to the mounting plate and was completely unable to turn. I eventually got it off, but the hole and the shaft will not go back together because of the crud on both surfaces and some dings. Does anybody have the actually measurements for these two surfaces? Or does it just need to be a slip fit? If I degunk/deburr the steel shaft then clean the aluminum will that suffice? Or is it more complicated than that?
Cleaning and especially deburring will fix you right up since the parts do not move relative to each other once chain tension is properly set and the big nut is tightened. Clearance between the two parts is not that critical as long as the cam can move when the nut is loosened.
My bad! It was related to his earlier photo of the worn cam tensioner. I thought if I replied to that post it would keep it together and not add it to his stream, WAY down stream!
(Still getting the hang of this forum. Love when I get an award for blindly stumbling into it)
