So...I'm about 3-4 months into my ownership of a 1984 XJ6. It's far from perfect, but given the low price paid I'm willing to put some money into it to get it at least close to a daily. As it stands I drive it probably 50 or so miles/week with no real issue other than the occasional fuse needing to be turned now and again. The only "major" work I've done so far is replace the fuel pump and fuel filter along with spark plugs/wires, air filter, etc. So nothing too involved.

It gets a bit of a tick tick after warming up, stethoscope seems to indicate from the exhaust head so I'm assuming a stake-down kit is in order (I've felt around under the oil cap and it doesn't have one). Roughly 135k miles, so it needs it whether it "needs" it or not. I've watched the videos, read the instructions on here and other forums, and plan on doing it this weekend. I've got a family member who has mechanic training - albeit more SBC than British - so he can help me out of most problems I get myself into.

I guess my question is - how much damage is "too much" to put in the stake downs? It seems to run fine, just gets kind of clattery once it gets up to temp. Is there anything else I should be looking for once I get the valve cover off? Or, assuming everything looks more or less like the youtube videos, do I just get them in there and move on? Anything else I should watch out for, or just check out, as long as I have the exhaust side valve cover off? And is it worth pulling off the intake side for giggles, as long as I have enough for both sides (it came with 6 of them, 3 on each side)? Or am I just asking for more trouble screwing with that other side? (I only have the gasket for the exhaust side, so I kind of have my answer there already)

I'll try to post pics of the whole ordeal if possible - if only to demonstrate that a very unskilled shadetree mechanic can (or maybe cannot) do the job.

 

are you using 20w50 mineral oil ?

leave the intake side alone. it doesn't need stakes.

make sure the oil passages are covered so no shards get in. Vacuum thoroughly afterwards.

Good luck.

 

Quote:

It gets a bit of a tick tick after warming up, stethoscope seems to indicate from the exhaust head so I'm assuming a stake-down kit is in order (I've felt around under the oil cap and it doesn't have one). Roughly 135k miles, so it needs it whether it "needs" it or not. I've watched the videos, read the instructions on here and other forums, and plan on doing it this weekend. I've got a family member who has mechanic training - albeit more SBC than British - so he can help me out of most problems I get myself into.

Good idea to install the stake-downs as a precaution although I tend to doubt that the noise you're hearing is from the tappet guides.

When/if the tappet guides move upward they come into crashing contact with the camshaft and get bashed to bits. This wouldn't typically be a come-and-go ticking noise

At 135k miles you might have a couple tappets that need re-shimming....which is a bit of a chore.

Cheers
DD

 

A guide with a few nicked up edges won't need replacing but a shattered one will.

When I worked on these cars everyday we had 'parts-engines' in the back of the shop that we took parts from.
I got really good at pulling tappet guides out of the heads and installing in the customer car.

I put the guides in the freezer or in a styrofoam cup with liquid R12 refrigerant to chill the guide.(R12 boiling point was 34 below zero or something like that)
The guides go in easier when they are cold.

The tappet guide holdown plates kept the replacements from moving again.

 

Thanks for the advice/thoughts. I'm wondering if anyone has any other thoughts on what my noise could be - I've got a couple quick videos from a few months ago that give a general idea as to the noise.

 

only way to isolate the tappets making the ticking sound is to install the stakedown brackets. If noise continues then the chain tensioner could be suspect, they have a vinyl piece that may be worn.

but in my limited experience the 4.2 liter and the 3.4 / 3.8 liter XK engines are not exactly "quiet", they always make a racket of some sort.

 

Put in the comeplete set of stake downs.
I had an inlet tappet guide come loose on a 4.2 engine.
Luckily caught it before any further damage

 

So, as promised - we did this over the weekend. It was a "work on cars" weekend anyway, and I've been saying this needed to be done since I bought the car a few months ago.



Before we started, I wanted to remove air pump/air rail stuff. I live in a non-emissions state and figured it would be nice to clean that up a little, plus it would give better access to the compressor, which is also on the list of things to get working - that's a whole other story. Anyway, I got the air rail and pump off and capped off any remaining holes without too much of a problem. Happy to have easier access to the rest of the engine and it just looks cleaner too:



Next came the exhaust side valve cover - I only did the exhaust side, since that's where the noise is coming and most people say that's all that's needed for stake down. So I pulled off my first Jaguar valve cover...and right away I knew we were in trouble. Two of the tappet guides were completely raised up and beat to hell. You'll see in the below pics - the 3rd and 5th going from front to back. The 5th was the one I immediately noticed and was the worst of the two, but #3 wasn't much better.



You'll see the 5th in the first pic above, the 3rd in the lower. Both were in bad shape. My brother in law (a GM guy) couldn't believe the cam lobes hadn't been completely flattened. Remember, I've been driving this thing 50+miles/week since I got it in March without issue other than the "tick tick ticking" I mentioned above after it got up to temp. So at that point we assumed we had a problem that was potentially too far gone, but decided to push through and see what we could do. Using a brass punch my brother in law got them knocked back down so the stake down plates would fit. Then we moved on to drilling into the head....

I bought the kit from a usual source and we carefully measured and marked out on the bit the depth for each screw, just like we saw in the videos/online explanations. We started drilling the first hole, got about 3/4 of the way to the marked spot on the bit and.....drilled through the head. Oops. ****.

Now what? Did we just irrevocably break what appeared to be an already pretty bad shape head? What did we just drill into? Was there water in there? Exhaust port? Some quick googling seemed to indicate it was an oil gallery, and it just didn't make sense to have screws that long that weren't meant to go through....so we decided to keep going. First we bought some shorter, self-tapping screws that wouldn't go all the way through for the rest of the plates (but still managed to go all the way through on at least 2 more). Eventually all three plates were installed and the tappets were, in some shape and form, "staked down".



We cleaned up the valve cover, put on the new gasket, tightened it all down and fired it up. Tick tick was gone. We let it run for a while to get up to temp, still no tick tick. Overall it sounded much smoother, no clatter, nothing but the usual noise from all the holes in the exhaust. Then we changed the oil, which had more flecks of metal than a pan at Sutter's mill in 1849. Some I'm sure came from our drilling, but I'm sure some (or most) was from those tappet guides getting beaten to a pulp for who knows how long. I've driven it probably 30-45 minutes since. It's still burning off a lot of oil that spilled onto the exhaust manifold when I took off the valve cover, but that's mostly burned off without any obvious new oil/leaks appearing. Temp and oil pressure are same as before. No tick tick tick or other clatter from the engine. I didn't take a pic after the valve cover was put back on - but it's all much cleaner and I like the little brass plugs on the air rail ports as well.

So what's everyone's thoughts - were those tappet guides too far gone? Did we ruin anything by drilling through the head into what I assume is an oil gallery? Is this a temporary band-aid? My BIL would love to just lump a SBC in there (you see his car in the first pic), but I prefer the original engine -- if it can be saved.

I'll be driving it to a small-town cruise night/car show in a couple weeks - probably 150 miles. It's made the drive before without issue, despite the tap tap clatter. I guess we'll find out in a hurry.

 

NOPE, some of mine were worse.

As all my Jags were, and are, Daily Drivers, Sunday is the only Jag Work day.

Just like the B I Law, knocked them down, staked them, drive on. That was 32 years ago on one of them. Still clatter free and God knows the current Kms, as that bit stopped rotating 20 or so years ago.

I did do both sides, but the exhaust were the culprits on the clattery engines. The others were quiet, but since the kits were there, and the beer was COLD, why not.

 

Any advice on how to not break through into the oil well? Like the original poster I’ve ordered a kit with self threading screws, but after he said he broke through I’m concerned.

 

From what I can tell, the kit I received had screws that were meant to go through. I'll also note that they were not self tapping screws, the kit came with a tapper. The youtube videos I've seen had kits with self-tapping screws that were quite a bit shorter than the ones I received. I'm assuming some kits are simply meant to have the screws all the way through, with others coming just short. If yours said it has self-threading screws, I'm guessing you'll be fine. Just mark your drill bit with tape or whatever so you don't go any deeper than needed.

I wasn't expecting to go all the way through and figured we'd made some sort of huge user-error. But a quick google search seemed to show that drilling all the way through isn't unusual and not considered harmful, a least not by some.

 

Thank you for the reply - certainly makes me feel more comfortable!

 

Got mine installed today! Broke through on one hole, and actually broke a bolt head off on another, but fortunately was able to back it out with vice grips. Feel like I did a good job cleaning up shavings. The middle one isn’t quite as snug on the tappet guides as I would have liked, but it is covering a portion and I hope that will be sufficient.

Waiting on cam/timing tools to replace some tappet shims before closing her up.