Oil consumption

[lo_zarro]

Hi mates!
how are you all?

i'm here asking for some advice about the oil consumption of my truck.. i've been riding for 6000km more or less, always on road since we're using the truck as an holiday car.
yesterday the low oil pressure light started turning on, i checked the oil stick and i noticed the oil was barely touching the tip of the stick!

i had to add a bit mor than 3 liters of oil..

it sound quite strange! actually, the last service has been made by the mechanic so i didn't check the oil level. Anyway, i've never noticed neither blue smoke, strange smells from the exhaust, oil stains under the car, emulsion in the cooling system..

what do you think? maybe it's time to overhaul the head (after the summer!)?

thank you!

 

[solarman216]

Never a good idea to let the oil get that low, if the light came on then your bearings etc suffered oil starvation, and nothing you can do about that now, do not know when you last changed the oil and filter but after running it that low I would be changing both and that is the best you can do, Rick

 

[lo_zarro]

you're definitely right.
i didn't expect the oil level dropping so much in just 6000km since the oil change.
The light just blinked as soon as moved the truck from my parking, and i immediately stopped.
I'll change oil and filter for sure, but most importantly i'd like to understand why the oil has disappeared!

 

[solarman216]

If you left it to your mechanic to change te oil and filter, did you check it yourself at that time? how do you know it was full to start with? 3 ltr is a lot in 6K if you are burning that much then you would expect to see blue smoke, you say there are no leaks, it all suggests to me that it was not full to start with and low oil will cause the oil to get too hot and just make matters worse, do your oil and filter change and them monitor it by dipping once a week, Rick

 

[lo_zarro]

i've been a dork not checking the oil level after the service.. but damn.. a bit of trust!
of course i don't know if it was full when i took it home, i was just assuming it..

today i'm leaving for Sardinia for a week, i'm changing oil and filter as soon as i come back home.

thanks Rick for your help, as usual!

 

[lo_zarro]

After 2000km across Sardinia, checking the oil level, i didn't notice any oil consumption.
quite strange indeed..

I only noticed that the loading cap isn't sealing correctly: some oil vapor leaks when the engine is running. i think i'll have to change it.

 

[solarman216]

Seems to point in the direction of it not being full to start with, would be worth checking your oil catch can and the hoses that go to it, unusual for the filler cap to leak, Rick

 

[lo_zarro]

for the oil cap, i noticed that it keeps turning while screwing it in. maybe the thread is damaged either on the cap or the tube, but at first sight it seems ok.

i need to check for some alternatives: the original cap is out of stock

 

[lo_zarro]

hi all (basically.. hi Rick!)
a couple of updates..

the truck is actually consuming oil: i was misreading the oil level.
i took the truck to a mechanic that confirmed the oil consumption.
at the end of the season i'll leave the truck at his garage to check piston rings, head and the turbo coreassy.

this way i guess the engine will turn new!

 

[solarman216]

Glad you have at least got something positive to work with, my guess would be the valve seals and or turbo, would not suspect the rings unless the engine has been well overheated in which case the bores could be scored, Rick

 

[lo_zarro]

i've made the same considerations..
the engine i hope has never been overheated: the previous owner was driving without thermostat, so the working temerature were a bit lower than usual.

the turbo has been checked by the mechanic and he said he didn't see any issue or leakage.

valve sealings is what i suspect more, based also on my previous experience (on motorbikes only). Anyway, with the head on the table it will be the time to check everything and be ready for 350k km more!


what about oil grade? i'm using 10W40 in my engine. what if i turn to 15W50? coould it be useful to reduce the consumption while i'm using the truck before the overhauling?
may I refill with a different grade or should I drain all the oil before refilling?

 

[solarman216]

Ah many points here first off running without a thermostat is not a good thing, it may make overall cooling lower but because the flow rate of the coolant is far to high it can cause cavitation at various points in the system which causes localised boiling, very bad for the engine, 15W50 may help but more important is to have a visual of the bores when the head is off, Rick

 

[Banshee]

i've made the same considerations..
the engine i hope has never been overheated: the previous owner was driving without thermostat, so the working temerature were a bit lower than usual.

the turbo has been checked by the mechanic and he said he didn't see any issue or leakage.

valve sealings is what i suspect more, based also on my previous experience (on motorbikes only). Anyway, with the head on the table it will be the time to check everything and be ready for 350k km more!


what about oil grade? i'm using 10W40 in my engine. what if i turn to 15W50? coould it be useful to reduce the consumption while i'm using the truck before the overhauling?
may I refill with a different grade or should I drain all the oil before refilling?

I use 10w 40 mineral in all my Terrano's Not sure on the science behind using 15w to reduce the oil consumption. I think I understand the logic that you are using however if the valve seals have gone, the oil will still be leaking past them just slower with a lower viscosity oil.

I'd be very interested to see some pictures of the engine rebuild on the bench mate :thumb2

 

[lo_zarro]

you're right Rick: in fact as soon as i noticed the low temp I checked and didn't find the stat in place. of course I bought it immediately.

Yeah, the logic is that! it's not a solution of course, but just a way to try to reduce the consumption while waiting for the repairing.

the mechanic usually takes some pictures while working.. let's hope! i'm really curious

 

[solarman216]

Let us know what your guy finds when he strips it down and yes pics would be good, Rick

 

[lo_zarro]

today the truck is visiting the mechanic (i'd like to check the turbo before the holidays).
yesterday i changed the heater hoses because they were very old.
removing the intercooler i noticed some oil inside (quite a bit indeed, it was dropping out keeping it vertical) and i'm way more sure that the turbo needs to be checked.

driving in the last weekend i also noticed that the truck starts smoking when in full torque, when the turbo start tu push.. another clue?

 

[solarman216]

I have yet to see an intercooler without any oil in it, some oil will always pass a turbo, Rick

 

[solarman216]

driving in the last weekend i also noticed that the truck starts smoking when in full torque, when the turbo start tu push.. another clue?

Blue or Black, blue is burning oil, black is too much fuel/not enough air, Rick

 

[lo_zarro]

definitely not black. white or better thin blue.

it's ok a bit of oil in the intercooler also for the vapour recirculation I guess, but is it normal to see a trickle of oil flowing out of the IC? isn't it too much?

 

[lo_zarro]

hi guys!
a very little update..
i left the truck to the mechanic a couple of weeks ago.
he's going to overhaul the turbo unit and the head.

we both suppose the head has a crack somewhere, since the coolant in the expansion tank is bubbling. he'll check.

the engine is going to be almost new after this open-heart surgeon.. at least i hope so!