Ok so I’ve gotten the xk8 running pretty good, and eliminated all the dash lights although the airbag light keeps coming back on…we’ll save that for later. Anyway, I’ve been doing a lot, and I mean a lot of reading about these machines and I have a lot of questions on a lot of topics so I’ll narrow it down to each specific section per thread. I’ve put about 500 mi on the car since buying it recently, and I’ve noticed a few things I wanna address. I plan on keeping this car for a long time and want reliability, as best as I can get it. My two main concerns at the moment are that I want to make it run perfectly, and then address the worn out suspension. So I’ll start with engine….

forgive me for asking questions that have been covered a million times but reading through old threads sometimes makes me more confused then inform me, so let’s dive right in to my questions:

So I have a very early production 97 xk8 coupe, last six digits of my vin are 001363. Through research it appears first vin was something like 001246, so I’m assuming I have a nikisil lined cylinder motor. No clue if it’s been updated/replaced I’ll check motor number tomorrow when I get car back from detailer. I don’t know if timing chain/guides have been updated either. What concerns me is after reading a lot about timing and nikasil stuff, I have noticed or found the following:
-when I changed spark plugs, there was a good amount of oil in each spark plug well.
-my paper type air filter is soaked in oil
-removing intake tube to clean throttle body, there’s visible engine oil in bottom of throttle body
So, i checked if the oil baffles are still in valve covers and they are. I checked full open breather tube and it’s clear, not clogged.
I also started to notice a rattle like noise upon startup from passenger side until fully warmed up.
I also noted that the thermostat housing is still plastic.

so, for now questions are as follows;
without removing heads how do I know if I still have nikisil cylinder linings? Or how could I tell or find out?
and how do I know or tell if timing has been updated short of taking timing covers off?

let’s leave it here for now and I do have a cylinder compression tester, but it’s more for small engines like lawn mowers etc. would it still work if I check one cylinder at a time by removing ignition modules so as not to start it on 7 cylinders and throw codes, testing compression on each cylinder one at a time?
any help appreciated, thanks

 

A very early car. If original, the motor will definitely be Nikasil. A dealer may be able to determine if the motor has been replaced, or look for a green label like this:


on the rear RHS of the block - although they can fall off. A replacement engine may well bear a number that is contemporary with the car's age (mine does).

Oil in spark plug wells will be the boss seals. I found a small amount of oil had collected in the TB on mine.

The first-gen tensioners could allow the chain to rattle as a sign that they are failing. It may be something else, but I would be very wary about even starting the engine until the cause is identified.

There's no way that I'm aware of to inspect the secondary tensioners without removing the cam covers, but you need to do that to replace the boss seals anyway. You may be able to snake a borescope down the front of the motor to check the primaries once the cam covers are off.

I would not be concerned to have a Nikasil block motor:- the consensus these days is that, if it's survived so far, it will continue to do so as the root cause (sulphur in petrol) was eliminated some time ago. Do get a compression test done if you're worried.

 

I have a 97 xk8 which had similar oil in plug wells etc. issues. Replaced the cam/valve cover gaskets. With the covers removed, it's easy see if the tensioners/guides have been replaced. On a 97, you could remove the vvt solenoid and insert a borescope to see the secondary tensioners. My car has over 100k miles and the Nikasil liners look like new. You should be able to get a Innova 3612 Compression Tester on eBay for about $25.

 

Oil in the intake plumbing is often due to plugging of the part load breather at the front of the left cam cover. Taking it apart without breaking the brittle plastic is not easy, but once you have the hose off use a 3/32" drill bit to open the port.

 

Michaelh and barnter: thanks for the great info and pics, very helpful.
so I got car back from detailer and I’m looking for a plate on the motor and can’t find one. Maybe fell off, maybe haven’t found it yet, maybe I’m looking in wrong place? I got a flashlight and a small mechanics mirror and I don’t see anything on the right hand side (drivers side USA) of block, although visibility is limited due to 1000 things in the way and a gap of mere inches between motor and body. I’m not too worried about the nikisil thing I just wanted to know for peace of mind. I’m more worried about the tensioners/guides as my car has 68k mi on it and last owner only put 10k mi on it over 15 years and babied it. I have absolute zero intention of babying this cat and drive it like it was made to do, it’s a “weekend car” and I love scaring the **** outta my girlfriend when we go for rides lol. The deal is I have to tell her when I’m gonna stomp on it and when we hit about 80mph she yells to slow down, even though I’m only in like 2nd or 3rd gear. Hahahaha
any way I’ll keep looking for the plate but thanks for all the info and suggestions, much appreciated

 

Rj237 I did this already and it was perfectly clean, nothing came out of port and I checked hose all the way to throttle body which was clear. I even pulled breather tube off pass side cover and can see the metal plate in valve cover.

my next thought was if there was some sort of other breather for engine that might be clogged like a pcv valve or a one way valve on a tube somewhere, but haven’t found any info like that yet.
but anyway that’s for the suggestion, much appreciated

 

I meant the 'other' RHS, lol. Looking forward, so your passenger side.

Please, please find the source of the startup rattle. If a tensioner lets go, you will have A Very Bad Day.

 

Yeah I will be looking into that rattle like noise tomorrow. I reached out to previous owner to see if he knew if timing was updated or not. Waiting to hear back….and I’ll check the other side of motor tomorrow for the plate. I also noticed in the drivers door two stickers for previous recalls, however one sticker is on top of the other im gonna try to see what those were for if I can too.