Hi all,

My manual Ralliart has now done 2500km since I changed the oil just after I bought it in February. I have just had to top her up with 300ml of oil so there is obviously some consumption going on. The is 91000km on the odometer.

There is no smoke at startup or at idle and no smoke on acceleration or deacceleration. The engine runs very smooth with no lifter rattle/tick. The engine looks pristine clean through the oil filler cap. It feels to have the sort of power that you would expect.

Service after purchasing it (myself). Nulon 10w40 synthetic oil and genuine filter, new air cleaner, front and rear platinum plugs, castrol syntrans transmission fluid, brake/clutch fluid flush, coolant flush. The PCV valve is fine (cleaned it anyway).

Do you think this is due to the oil viscosity or just normal oil consumption for the kms? I was under the impression that the 6g74 engines only really use oil through worn valve stem seals unless the kms are very high. Its just the first engine I've had that uses oil since my first car 24 years ago (VH Commodore - now that was a bad car).

Steve

Viscosity is fine. The Nulon should be fine, unless there's something I dont know about the Nulon oil.

No obvious leaks? Camshaft end cap or distributor seals. Camshaft seals etc. Though at 300ml in 2500km you should spot a leak....

I understand the Magna's are prone to leaky valve guide seals. You may not notice it burning oil as it only burns a little under certain conditions.

Blow by maybe? I have a kind of clapped out old executive, fitted with an oil catch can - even on Penrite 5w60 I get oil in the can. Maybe not 300ml in such a short distance, but still oil.

1 - Check for oil leaks.
2 - Check the plugs, see if they're oily.

Have you had a look for any leaks or wet patches on the sides or bottom of the block or heads?

Head gasket maybe?

No visible oil leaks. Engine dry as. I'll pop out a couple of plugs out and see how they look. I only just removed and replaced the original platiunums and they looked good for their age, no oil etc.

If there was a lot of blow by, I assume the PCV valve would be really oily?

I just had another good look. The plugs a dry (front ones only checked!) but there is some oil on the front of the block on the passenger's side - not enough to drip on the ground though.

Steve

My opinion only, but I'd suggest that 300ml in 2500km is quite OK - that's basically only a cupful of oil. Some questions, were the dipstick readings taken with the car on level ground, was the engine temperature the same, and finally were the readings taken just after engine switch-off or after an hour or so to enable oil to drain fully from the valvegear etc.
The dipstick is a very primitive way of measuring oil level....cheap but not precise.

Good point. All readings taken in garage with flat floor about half an hour after stopping car. I agree 300ml is not terrible but still surprising as I've never had to add oil to any other modern car (including TF 3l and 380). I know some consumption is normal and there may be a slight oil leak so this could be enough to explain the drop.

Steve

Going back a few years, after you changed the oil you would have to top it up again in a day or so to replace 'lighter fractions' in the oil which boiled off once the oil reached operating temperature.....times have changed.

I suspect that you will find that the valve stem seals are starting to go.

When the engine is warm, then let you car idle for a couple of minutes. Blip the throttle. Is there a cloud of Blue smoke out of the exhaust.

You will find that the problem will continue to get worse.
My car is now at 150K, goes through a dipstick worth of oil every 2 weeks.

Time for the heads to come off, clean up, new seals etc.etc.
Gerry

Dont worry about it, dont worry about rings, stem seals etc etc. YOu are using synthetic oil, it is perfectly normal for some useage

ALL cars use oil, is the way an engine works, the difference is with a mineral oil the useage will be masked by other things like moisture etc which will work its way into the oil this keeping the quantity up. With a full synth oil, it will not absorb any of this stuff and thus you will get a drop on the dipstick.

If you do have a weep, check things like rocker cover gaskets and most important the thrust cap seal at the end of the front head, either way, I would not be too concerned with the useage given you are running good oil

My old engine had 300,000 on it, never consumed any oil, was using 10-40 oil aswell (Royal purple), another thing when you changed the oil did you let car idle for a bit & check again, you might find that missing quantity was sucked up by the filter.

As Mal said, oil usage is normal. As for how much, it can heavily depend on how hard you drive it. The higher you are reving out, the more blowby is produced, and therefore the more oil you lose. Driving fairly hard, you will need a semi-regular topup. The breathers are vented in 2 places - The PCV, and the rear rocker cover (just before the throttle body). The rear breather is the reason it is a good idea to clean out your throttle body fairly regularly for better throttle response.

Thanks for all your input. I checked the oil again after getting back from work. The level is now 5-10 mm ABOVE the top indent so I am wondering if the level was right all along? Very confusing. I'll keep any eye on it and see what happens.

Steve

And the oil had always been checked in the same spot after a run. Can a crankcase air pocket form near the dipstick?

I remember when I bought the car the oil was down on the dipstick and fine when I checked it after we drove it back home. Very strange indeed but a great car overall - drives as new after 9 years.

Steve

Will clean the throttle body. One thing I haven't done yet!

Only thing left is timing belt but I'll leave that to my mechanic.......

Steve

check ur oil in the morning... after the car has been siting over night, this is what i do then u get an accurate as possible reading as the oil in the engine has drained back into the sump.

Just checked my ralliart after 5000kms of driving and oil is still at the full mark.

Just an update. Now 3000km since oil change and topping up with 300ml of oil. Dipstick still reading 5mm above full mark. The low reading must have been due to an air bubble or the like in the sump. I cant explain it otherwise. I actually dont think it is using any oil, which is a good sign. But as Mal said, 300ml isn't that much over 2500km. There are lots of new European cars using much more (due to their low friction engines and very thin oil). Landcruiser v8 diesel owners are putting up with a litre every 1000-2000km and Subaru have had some problems in recent times.

We are doing pretty well really!

I think I have worked out what happened. The two times I measured the oil I had just moved the car. The engine was cold but I think as the oil pump had pumped oil to the heads, the cold oil didn't drain as completely back to the sump. I did the same today and the level was down. Went for a drive and on rechecking it hot, the oil level was fine. I just didn't think this would make this much difference.

Steve

your oil consumption is normal.

Girlfriend's Getz 1.5 goes through 1 litre of oil per 2000km lol, and that is within normal tolerences hahaha she does 2000km a week sometimes...

Now at 6000km and no change in the level.

Steve