3.0L V6 Oil usage

[DRJonesy]

Hi all a question from a newbie.  I have a 3.0L V6 2006 which I have had for just over two years.  I bought it with 53K on the clock (FSH) and it has now done 110K.  The engine is as sweet as a nut with no rattles, undue noises and I have changed the Oil every 10K using a fresh filter and Castrol Fully Synthetic 5W-30.  It does not smoke or leak Oil.  Just after I bought it, I had the sump gasket replaced because it was leaking a bit and the car had only covered a few thousand miles in the prior year.  This cured an obvious leak from there, however, it is still thirsty for Oil.  I drive high motorway miles and have to keep a keen eye on the oil level topping up with a fresh litre every 2-3K or so.  Do other AJ-24 V6 owners find that their oil consumption is similar or is this unusual?  It must be going somewhere and it's not leaking out so it must be being burnt but I reiterate - there is no discernible smoke under any load or throttle conditions.

[Russ68]

Hi there,

Can't say i have this issue on my 3.0, but I don't do the mileage you do. TBH a litre every 2-3K is not too bad so hopefully doesn't point to a big problem, which I'm sure you'd be aware of as you seem to know your stuff and be doing the right things.

Apparently the A series as in the old Mini was designed to burn a pint every 800, from new, which is shocking! I had a 850 that used a gallon a week and I was spending almost as much on Oil as I was on fuel, before it blew up anyhow! Luckily things have come on since then!

All the best, Russ

[JOE-DOT-COM]

hi

if its using Oil and is not leaking, its either valve stem seals or piston rings

valve stem seals will show more when you first start it, after its stood a bit, usually a bit of smoke on startup them it clears, it can show also if you coast in gear down a incline and then hit the throttle, small puff of smoke, its usually age with valve stem seals as they go hard and they pass a bit

rings, will smoke on coasting and also when the engine is revved hard

compression test will usually show how good the rings are and is quite easy to do next time your changing the plugs

I've also known on quite a few cars for the crankcase breathers to block up, there usually on one of the cam covers, not sure on the jags would have to look, these block up, most modern cars usually have some kind of valve that slightly pressurise the system and then vent off into the induction system, so any vapors are burnt off. problem is as they get older the filter/gauze blocks up and you get much higher pressure in the crankcase, this causes the vapors to be forced past the piston rings cause smoke and excessive Oil consumption

cheers

Joe

 

[DRJonesy]

Cheers guys thanks for the advice.  I have just changed to plugs so probably wont check compression unless things get much worse.  Don't see any Oil smoke on start up or coasting so sounds from your advice that it may well be normal consumption anyway.