oil burning question

[pyro]

Ok so today my engine oil low came on... So i added a quart because that how much it was down. So now I'm at ~1500 miles and have burned or otherwise lost 2 quarts of oil. I have no leaks that I'm aware of. Could there be a leek that only leeks when dirveing and doesn't leave even a single drop on my driveway? Can It be sucked through the pcv line? That line is all oily where it connects to the intake boot. I didn't burn as much oil when i was running 20w50 but then i found out that i should switch to 10w40. So this is my first oil change on 10w40. What I think may be contributing to it is i do drive the car like i stole it. It does spend alot of its life above 4500 rpm's. What I'm trying to find out is, is there anything i should be doing right now to test to see if its valve seals, ring leakage , or any other way that oil is getting out of my oil pan.


EDIT: I am now at 174,500 miles

[BMWDriver]

Considering how old the car is and how you drive it, your consumption seems normal to me. I use 1 quart only at about every 1500 miles as well, but I can't say I drive like I stole it. So, the more your pistons explode per minute, the more you'll be burning that oil.

Out of curiosity, synthetic or regular ?

[e39dream]

if it was burning 2 quarts every 1500 miles there would be no living insects in your town from all of the smoke- it must be leaking out as you drive, possibly a rear main seal. also check your coolant (on a cold motor) and look for oil in it.

[pyro]

yah the coolant is fine no traces of oil. I just find it hard to believe that there could be a leak that only leaks when driving and not leave a drop on my driveway. Ill check the rear main but it would leave a stain under the car where the bell housing is so i dought it.

[Qsilver7]

When's the last time you had the valve gaskets replaced? You have the M50 engine, right? If you remove the ignition coils...you can check to see if oil is pooling down in the spark plug wells...if it is...then that could be where your oil is disappearing to. There also wouldn't be any tell tale signs left on your garage floor or driveway.

[pyro]

Yah i had them out not to long agao when i changed the sparkplugs i should check that, I think im going to go and do a leak down test at work tonight or tomrow. And heres my pcv valve or pipe I should say because its just a open pipe with no mechanical part at all. Is this how they actully look like?

[Ross]

Oil in the PCV is an indication of worn piston rings as is high oil consumption.
Sounds like it's tired. Keep oil in it and change it more often as the blowby contaminates the oil.
If your climate is warm enough you can run a heavier oil to slow down the consumption.

[pyro]

so drive it til' it dies huh?

I don't understand though becasuse i have 210 psi across all 6 cylenders. I guess I should do a leak down test.

[Alexlind123]

I dont use any between changes, so i wouldnt call that normal...

[joshua43214]

I know it sounds hokey. But try tossing in a quart of Marvel Mystery oil. Its not the mechanic in a can that they would have you believe. But I have seen it help the oil rings on pistons a bit and lower oil consumption on old worn out engines. It can't hurt, its cheap, and may even help a bit.

[Russell]

Could be stuck oil control rings or worn valve guides. If stuck pistion rings try Auto-Rx engine cleaning product. Google for it. it is known to clean rings and remove sludge. Very gentle product. Used it on my car and seemed to improve performance and smoothness after things were cleaned out.

As for valve guides. I believe replacement is the only answer. I drove my 1983 e28 for 100,000 miles with worn valve guides using 20w50 and Bardol No-smoke every 800 miles with minimal smoke. I should have fixed it. However, I had three children in college at the time.

[Rory525]

My car uses about 1 litre of oil per 2000 miles, the M50s seem to use a little as they get older. Definately uses more if I drive it hard. I use 10w40 as well.

Theres been a little oil on maybe 2 or 3 of my plugs when Ive changed them, so I guess the valve gasket is letting through some. Is it hard to change?

[pyro]

valve cover gasket is a breaze just don't over tighten the bolts. I've done a few at work. And as for valve guides i know mine are shot as when i start it up cold in the morning i get a puff of blue smoak and then thats it... Could enough oil get in there to cause that much oil loss? And my plugs are very clean last time i checked. And about the mistory oil now that you mention that i used that when i swiched over to 10w40 and thats when i really noticed a burning of oil...

[632 Regal]

use the crap as mentioned as a cleanup for the oil control rings. if they are clogged with **** you will burn a ton of oil like you are now. definetly worth a try as the oil rings shouldnt be wasted yet unless it was dino oil all its life without regular changes.

[BillionPa]

sounds like your old oil didnt provide enough piston ring protection, and its letting lower viscosity oil seep through.

an Auto-RX treatment should get rid of any crap on the rings preventing them from doing their job, and a bottle of Valvoline Synpower oil treatment per oil change should provide addition protection AND repair to the piston rings.

[pyro]

yah its always been dyno oil and i know iv kept up with oilchanges. Would a swich to synthetic change anything?

[BillionPa]

what was the change interval on your oil before?

a switch to synthetic may actually make the leak worse, unless you auto-rx it for 2 cycles first.

[jbourke]

And heres my pcv valve or pipe I should say because its just a open pipe with no mechanical part at all. Is this how they actully look like?

That's how they look ... and it being a bit oily is completely normal.

[pyro]

I have no idea what the change interval was before, but its 3000miles now...

[bmw_ryder]

the same problem i have it too;i drive the car from the signature.
should i check the spark plugs too see if they are with oil on it,in that case should i change the valves cover gasket?and if the sparks aren't weat should i clean the engine with an aditive?
consumation 1litre at about 1600miles