After being driven and sitting for a few hours, or overnight, the next time the car is started it briefly puts out a big cloud of blue smoke,which stops within a few seconds. After that, no visible smoke at all. My best guess is valve seals, since the symptoms are classic to that problem (the car has only 60,000 miles on it). I'd be curious to know how common valve seal replacement is in the 1997-2003 MY's; I've not read that it's a common problem. Also, has anyone done this job themselves? I've changed them on older 6 cyl. Jags, but not on a V8.

I'm waiting to get a cost estimate from my mechanic and, in the interim, am going to change to a higher viscosity oil to see if that helps any.

 

Take the breather hose off the passenger side valve cover and look inside and see if the foil baffle is still there.

Several people on the forum has said their baffle is missing and causing excess oil to get into the TB.

As far as the seals go, ask an indy mechanic how big of job this is and I would ask several.

Good Luck!!

 

I would also consider changing the oil from 5w30w to 10w30w and see what takes place.

 

Thanks Randy! Already checked and replaced the breather hose, and I've never had any trace of oil in the air filter or throttle body (wish it were that easy, believe me). So that leaves the valve seals, I'm afraid.

As I previously stated in my first post, I've done this job several times on 6 cyl. Jags without a problem. Given all of the issues with tensioners (just replaced by my indy mechanic) and the possibility of problems in removing and replacing the intake cams, I'm probably better off having it done by my mechanic. After all, it's only money.......

 

Hi Gus,

Going to try a 5w-40w synthetic oil. Nothing to lose at this point.

 

Just an FYI my 99xk8 has a little over 120,000mi and I have been using 10w30w for the past 10 years and I run it for 6000mi between oil and filter changes.

 

You want to up the first weight and not the second and is 5w-40 even on the list of jag approved oils?

You could end up doing more harm than good.

Be careful, modern engines are very easily upset by using the wrong oil weight.

 

If you look in your owners manual you will see that you will not go to Hell for using 10w30w. Look at the climate rating and the oil that is associated with it, if you fall into that category I say use it. I would not knowingly tell you something that would harm your car.

 

Wasn't aware that upping the first number rather than the second number would accomplish what I'm trying to do; raise the overall viscosity of the oil. It got 5w-30 the last oil change, and I guess I assumed that moving up to 40w would be the logical way to go. In any case, I'm going to err on the side of caution and put in 10w-30. Thanks for the tip.

 

Here is an oil weight explanation, this should help you out. When you have a cold engine, the first number comes more into play and as you heat the engine up, the second number comes into play.

Motor Oil Viscosity Grades Explained in Layman's Terms

 

Thanks Randy,

I also did some research that pretty much tallies with the article you referenced. If I read it right, going from 5w to 10w won't effect viscosity at engine operating temperatures so, 5w30 and 10w30 are essentially the same in that regardil. 5w will give me the benefit of easier starting and better initial engine protection in cold weather. Going from 30 to 40 weight would ensure that the viscosity is higher at engine operating temperatures, and might possibly reduce the amount of blue smoke when starting cold. Now I know just enough to be dangerous. I'm afraid the jury is still out.

 

If I am correct your concern is is the smoke on cold startup if that is the situation moving to a 10w30w is more appropriate. Looking at the owners manual it suggests that 5w30w is in the range of -25F to 130F the 10w30w is in the range of -5F to 130F so the range is well within the temperature range in your area.
Now for your FYI the puff of smoke on startup leads me to believe that your oil is reaching the chamber from the valve guides. That normally occurs after the car has been sitting for a long time. I know this because it is the same scenario on my 93 4.0 xjs the fix was 10w30w oil. Would I go to a 5w40w not me.

Link http://www.bobistheoilguy.com/motor-oil-101/

 

The bobistheoilguy.com link was really interesting, and went a long way to addressing my concerns as well as providing me with a great deal of information (my head is still spinning). Based on what I've read, your suggestion of 10w30 seems to make the most sense, because the oil becoming slightly "thicker" as the engine cools down might slow its migration into the cylinders. And, if it doesn't, I'm no worse off than I am now, and I've not put my engine at any additional risk.

Thanks to all that responded; your suggestions and support are greatly appreciated.

 

Hi Gus, yes, me too. I'am a synthetic 10-30 kinda guy. My opinion is the oil takes quite a beating with a warm engine, summer days doing highway speeds. I find engines with multi cams run cooler with a little thicker and synthetic oils . Living in NY, temps usually are now lower than the 20's during winter. However I am sure the debate will continue. Rich

 

https://www.jaguarforums.com/forum/a...-600-03am3.pdf

Hmmm sounds like you've become another victim of the part load/cold start oil orifice?

 

Tried cleaning the orifice previously, but it didn't seem to make a difference. Changed the oil yesterday and we'll if that helps. If not, the cost and trouble of installing new valve seals isn't cheap, but oil is, so unless it starts fouling plugs, I'm not going any further.

 

Give it a little time.