1uz possibly burning oil.

[Z2TT]

Hi,

It has been 3 months since I last changed my oil. I checked the oil level now and it is at the low mark. My engine does not have any leaks anywhere. So where is this oil going, it doesn't smoke so I wouldn't think that it is burning oil, but how can I definitely know it isn't burning oil, any tests?

I have checked my coolant and no sign of oil in it.

Thanks.

[hosking1991]

I was told by a mechanic mate that oily spark plug threads indicate worn stem seals so inspect spark plugs

Also may be a silly question but when you did the oil change did you check the dipstick level to see it was indeed at the full mark (eg: you may of put the acquired amount of oil in)

Luke

[Sciflyer]

The 1UZ can suffer from hardened/cracked valve stem seals just like the JZ engines

This is not necessarily related to km's done but age as well, my low-km car has it, you will get occasional smoke on startup and gradual consumption of oil

Its not a major deal and unless its really bad is not really worth pulling the engine apart to fix but the problem can be lessened by changing to a thicker oil

[CrUZida]

How often do you give it heaps of herbs?

I find if I drive like a granny then it uses SFA oil between changes, but if I give it a lot of schtick (such as a recent drive to Gero) then it uses a lot more oil.

[Z2TT]

Well I don't notice smoke on startups, I drive normally, bit of foot here and there but nothing too much.

[Sciflyer]

what grade oil are you using and how many km has your car done?

[Z2TT]

15w-40 and the car has done 80,000km.

[Kedderz]

Im assuming thats odo indicated or is it indicative of the condition of the rest of the car?

[CrUZida]

AFAIK he has an aussie delivered LS400, so the km's are probably genuine.

I use 15W-60 in mine (Penrite HPR15)

[RA35GT]

I use HPR15 also, dont notice much of a drop in oil level between services (although i do them at 5000km's which is roughly 3-4months). I may drive like a nanny however LOL

[Z2TT]

Actually mine is a Toyota Celsior, Yes the reading is from the dash.
Mobil1 Super1000 15-40 I use.

[Z2TT]

Hi,

Oil is now topped up at the correct level, so I'll see how long it takes until I begin noticing the level drop.

[Javal]

Hi,

Oil is now topped up at the correct level, so I'll see how long it takes until I begin noticing the level drop.

Check it weekly, make a note of how far off full it is every week.

Do a dry / wet compression test to see if it's rings (however if the 1uz has a known problem with valvestem seals it's more likely that).

[Z2TT]

Thanks, I will check weekly and also do the compression test, when doing the wet test, how much oil should I poor into the cylinder, and do I have to wait a while before to allow the oil to settle in the cylinder or can I screw the comp tester right back in and crank?

If it were a problem with the valve stem seals, wouldn't I get a puff of black smoke when turning the car on or when taking off from the lights?

Thanks.

[Javal]

Thanks, I will check weekly and also do the compression test, when doing the wet test, how much oil should I poor into the cylinder, and do I have to wait a while before to allow the oil to settle in the cylinder or can I screw the comp tester right back in and crank?

If it were a problem with the valve stem seals, wouldn't I get a puff of black smoke when turning the car on or when taking off from the lights?

Thanks.

Generally about 5-10ml of oil per cyl. I don't really wait at all (although dicking around yelling at your helper to crank the car while you hold the throttlebody open i usually waste about 10 seconds

black smoke is from overfuelling, blue from oil. It blows no smoke at all? Even then it doesn't HAVE to blow smoke to have valvestem seals that are on the way out.

Was the oil quality ok when you drained it? i.e. not jet black?