I've noticed that the KH is using a little oil. i.e.: the level is dropping noticeably between changes. Theres no smell and I cant see any smoke from the exhaust or any oil drips on the ground under the car.
The rocker covers look to have some caked dirt around the seals but not too bad, otherwise no sign of a leak.

Whats the most likely reason? Its done about 235k's now and rocker covers havent been done in a long while. I dont recall ever replacing the stem seals or anything.
Can it be the piston rings at this age? Seems to be driving perfectly fine.

All sounds perfectly normal!

All sounds perfectly normal!

+1

TJ @ 144,000 km and TL @ 170,000 km both need about half a L. of oil in the middle of the oil change period, so yours is doing ok.
The oil will be going past the valve stem seals and oil rings, but not enough to create blue clouds.
It will slowly get worse, so keep an eye on the oil level.
Driving style, the sort of trips you do, oil viscosity and brand of oil all have some influence on how much oil the engine burns.

So is replacing the oil rings not worth it?

synthetic oil seems to get lower quicker because it dos not absorb fuel like mineral

My KH was blowing smoke when I bought it nearly 4 years ago, but I found using Nulon oil for high k motors is good for it, it had 203,000 on it when I bought it and it has 270,000 now and it only blows a little blue smoke when idling for a long period, no need to spend money on it for a couple more years I think

warm motor, leave to idle for say 10 minutes, give the engine a good rev and look for any signs of smoke

So is replacing the oil rings not worth it?

Your choice.
By the time you have removed the engine, dismantled and reassembled with new rings, you are looking at a costly exercise.
- full gasket set.
- set of rings.
- other work, while you are in there (bearings, cam belt, etc. Head rework - new stem seals.)

A couple of $K, a few days work.

A bit of oil burning is to be expected with your car's age and odometer reading, my TJ (just under 300,000) is much the same. Only time I notice smoking is after idling a warm motor for a while, as Madmagna mentioned above (eg. after a carwash). A blocked PCV system can also cause excessive oil consumption with similar symptoms to blown rings or valve stem seals (ie. smoking when revved after warm idle).

FWIW, my engine was using quite a bit of oil.
It is at just over 200,000 currently.
I replaced the valve stem seals 3,500km ago and since then the oil level hasn't dropped at all.

Kinda hijacking here, my KJ has a slow leak and is going through a fair bit of oil, apparently it is the main rear seal :/ In a previous thread it costs around $600 to fix.

I bought the car from a dealer w/warranty, any chance I can try get them to look at it?

Car was purchased w/207xxx Ks, now has 212xxx.

This turned out to be the rocker covers. Big thank you to Mal, Brendon and the rest of the team at MitsFix!

Well, its back. Noticed the level is a little down after 10,000 km's or so.
I thought the new rocker cover seals had sorted it, but seems they havent.
Will have to check for more leaks.

235 thousand on the engine and you complain about the oil level dropping in 10,000 km?
Am I missing something here?

For what it's worth, my engine is at 214,000km and after replacing the valve stem seals around the 196,000km mark, the oil level doesn't drop at all (9,000km since last oil change)

I've noticed that the KH is using a little oil. i.e.: the level is dropping noticeably between changes. Theres no smell and I cant see any smoke from the exhaust or any oil drips on the ground under the car.
The rocker covers look to have some caked dirt around the seals but not too bad, otherwise no sign of a leak.

Whats the most likely reason? Its done about 235k's now and rocker covers havent been done in a long while. I dont recall ever replacing the stem seals or anything.
Can it be the piston rings at this age? Seems to be driving perfectly fine.


Well, its back. Noticed the level is a little down after 10,000 km's or so.
I thought the new rocker cover seals had sorted it, but seems they havent.
Will have to check for more leaks.

Define noticeably in this instance. How much to oil you have to actually add between changes? Is it actually enough to warrant a top-up?
I'd say anything under a litre per 10,000km is normal for a 15+ year old, 235,000km engine.

I personally don't think its worth addressing. The simple reality is it's not a reliability concern, the cars going to keep working just fine. It doesn't affect operation in any noticeable way (unless its billowing clouds of smoke) and the act of topping up once in a while costs peanuts
It's purely one of those 'in the back of the mind' issues that is entirely up to the individual. If it bugs you enough to address it then you need to open your wallet and fork over money. If it doesn't you keep driving with zero hassles whatsoever and save a lot of money

Speaking of topping up. I got completely sick of forking over absurd sums for motorcycle specific oil, which is often 4x or more the price of car oil. I've sinced moved to Delo 400, pick up a 20L drum for $88. LOT of people use it in absolutely everything including highly tuned forced induction motors with great results. I now use it in everything I own. The car seems extremely happy on the stuff. It's so cheap that even if you were religiously obsessed with short interval changes and keeping it topped up, it costs you little more than the loose change in the cushions

Well, its back. Noticed the level is a little down after 10,000 km's or so.
I thought the new rocker cover seals had sorted it, but seems they havent.
Will have to check for more leaks.

A motor will use a bit of oil, you can't expect it to use nothing at all after 10,000 k's, my KJ has used half a litre in 5,000 I'm so amazed as I haven't had a car thats been that good on oil since I had VL Commodore back in 1991, I also have a KH it uses about a litre every 2000k's and always has since I bought it 5 years ago, valve stem seals are worn but not worth paying someone to replace them.

Have you checked the distributor O-Ring? These get hard and leak over time.
When the engine is cold, get hand under the distributor and with your fingers, feel around where the head and distributor meet. Any fresh oil? If so, degrease it, dirve for a few days then check again. If fresh oil again, replace.

Mine would leak around 1ltr every 10,000km also, changing the rocker seals etc wouldn't do it, then found the distributor O-Ring was leaking, now, it hasn't dropped.

Although, I'm lucky to drive mine once a month now, but level hasn't changed when I do drive it.

235 thousand on the engine and you complain about the oil level dropping in 10,000 km?
Am i missing something here?

lol...

Define noticeably in this instance. How much to oil you have to actually add between changes? Is it actually enough to warrant a top-up?
I'd say anything under a litre per 10,000km is normal for a 15+ year old, 235,000km engine.
Was about half a litre I'd say.

Have you checked the distributor O-Ring? These get hard and leak over time.
When the engine is cold, get hand under the distributor and with your fingers, feel around where the head and distributor meet. Any fresh oil? If so, degrease it, dirve for a few days then check again. If fresh oil again, replace.

Mine would leak around 1ltr every 10,000km also, changing the rocker seals etc wouldn't do it, then found the distributor O-Ring was leaking, now, it hasn't dropped.

Although, I'm lucky to drive mine once a month now, but level hasn't changed when I do drive it.
Thats a good idea, i'll check it, thanks Grelise.

As for not worrying about it, so long as theres no actual leak i'm not worried at all.
Not going to worry about worn stem seals or such, if i worried about stuff like then I may as well overhaul the engine!
The cars running fine, quite strong actually.
But I do want to make sure that theres no external leaks anywhere.

If you have an actual leak of that magnitude, you'll notice it on the ground where you park. If it's not dropping oil and there's no leaks under the bonnet, you're consuming it.

I assume you are using a synthetic oil? They tend to go down more quickly between changes than a mineral oil - particularly if you've just swapped over. When I changed my third gen onto synthetic, the oil consumption went from zero to about 500-750ml/5k. No leaks, just being consumed. It has settled down somewhat after a few changes, but still goes down a bit between services.

Yes, went from mineral to full synthetic past few changes.
No oil drips on the ground, but i want to check the nooks and crannies under the distribitor where oil may sit.