Burning oil - BMW Forum

cap530 · 03-18-2008, 10:45 PM

Hi everyone,
This is my first post. I have a 2001 5spd Black 530i w/sport package. I have 173435 miles on my car. I need to add 1 quart of oil every 700 miles. I had a oil leak but I got that fixed. It was the gasket for the oil filter mount. No smoke from the exhaust. No oil drops on the floor. I know adding a quart every 1000 miles is typical. Does anyone have any suggestions?
thx
cap530

dresslered · 03-19-2008, 09:11 AM

If I had to guess, I would suspect that you have leaky valve guides, however, the piston oil control rings might be worn. Start off with a leak down test to see what kind of compression you have. This can sometimes indicate whether the compression loss is in the valves or not.

P.S. Adding a quart of oil every 1000-miles is not typical

cap530 · 03-20-2008, 12:21 AM

How when I know when it worn out? It doesn't look like I'll be getting as many miles as you. thx

dresslered · 03-20-2008, 09:41 AM

Well, I would hardly say that it is worn out. I am not familiar with the details of your particular year of engine, but BMW builds one of the best Straight-six engines around. It could be as simple as a check valve, but based on your mileage, I would suspect the valve guides. Shouldn't be a job that would break the bank, but try to have this diagnosed before jumping in. If it is however the oil control rings, I do know on some models you can actually pull the pistons out through the bottom of the pan thus saving the cost of a complete rebuild (and engine pull). Find a good mechanic that knows the car and see what he suggests. Regardless, you still have a much nicer car than many of the new vehicles being sold today.

Torque · 03-20-2008, 06:56 PM

Quote:

Originally Posted by dresslered

If I had to guess, I would suspect that you have leaky valve guides, however, the piston oil control rings might be worn. Start off with a leak down test to see what kind of compression you have. This can sometimes indicate whether the compression loss is in the valves or not.

P.S. Adding a quart of oil every 1000-miles is not typical

You might not like it, but that's normal, tolerable consumption for pretty much all engines ever made according to the manufacturers.

dresslered · 03-20-2008, 10:06 PM

Torque,
I am not going to argue with you as to what the bean-counters are pushing at their respective companies (sore subject), but I will hold true to my claim that an engine should NEVER consume that amount of oil (ask the engineer at the same company). An admission would merely be grounds for a recall program.

Oil consumption does not mean that you will not pass a smog test.
Oil consumption does not mean that you cannot drive the vehicle.
Oil consumption does not mean that the vehicle is less reliable.
Oil consumption DOES mean that the engine will not perform as well as an identical engine that is not consuming oil.
Oil consumption DOES mean that the engine will not last as long as an identical engine that is not consuming oil.

By the way, have you ever heard some of the British specs? There are some that allow for a "controlled seepage" (leaky seals) which equates to a puddle on the garage floor and oil loss. Not exactly what I call extreme engineering, but I still love the MG in mine.

94BMW325i · 03-21-2008, 02:13 AM

have you tried parking your car under a piece of cardboard, or something? Or tried degreasing everything on the car (oil pan, etc) then seen where it drips from?

cap530 · 03-21-2008, 04:43 PM

Quote:

Originally Posted by 94BMW325i

have you tried parking your car under a piece of cardboard, or something? Or tried degreasing everything on the car (oil pan, etc) then seen where it drips from?

Before I had the gasket changed, I had my engine steam cleaned. Wow it looked nice. It made it easier to find the leak. Now about 3000 miles later, I'm still burning oil. I have no leaks on the floor and no smoke from the exhaust.

I'll look close into the engine for oil.

thx