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RE: M52 oil consumption?

schneller — Wed, 02 Apr 2008 10:21:09 GMT

Ken,

The cyclone separator & the crankcase breather are the same thing.

However, in the winter the separator accumulates water & it will freeze up, even in those that were replaced! This happens more frequently w/ cars that are driven short distances and w/ extended oil service intervals which allows for more water vapor to accumulate w/in the crankcase.

There is a cold climate version of the separator & its associated lines. It is that version which should be installed when these valves are replaced. Also, it makes no sense to replace just the separator & one line, all the lines including the dipstick tube should be done when this job is performed. The dipstick tube has an integral drain that clogs solid & won't allow oil to return to the sump. Hence the only way out is via the throttle body. Given that the system has exploded 2 times from excess crankcase pressure points to a problem w/ the valve.

Relative to your speedo & wheels... 235-45-17 is the recommended tire size, which has a rolling diameter of 25.33 inches. Your 225-45-17s have a rolling diameter (when new) of 24.97 inches. Your snows are spinning faster hence fooling your speedometer & you into believing that you're traveling at a higher rate of speed.;)

Mike Morris
Schneller BMW Performance
26 Middle Rd
Newbury, MA 01951
978.465.2002

RE: M52 oil consumption?

KenM10759 — Fri, 28 Mar 2008 07:51:48 GMT

[quote][b]schneller (3/27/2008)[/b][hr]If you drive the car briskly (80 mph highway cruising), it will use oil. 1 quart in 3500 miles isn't out of the ordinary.
Should the car use more, I'd rule out a clogged crankcase breather system before anything else.

[/quote]

Been done, I think. The "cyclonic separator" system clogged and blew oil all over the right side of the engine at about 87,000 miles (it's now over 120K.) The valve and a hose got replaced under the CPO warranty. Less than 3 weeks later, it blew apart again, only worse. It took out nearly every hose associated with the cyclonic separator, and the valve itself again. Nice enough, the dealer who serviced it under the warranty (Wagner BMW, Shrewsbury MA) didn't whack me with the $50 deductible again. Is this cyclonic separator the crankcase breather system?

As for cruising speed, I have an interesting story (to me.) I drove the Mass Pike everyday to & from work, right up until I got laid off/resigned my job (mutually agreeable parting) on Wednesday. I would generally run at an indicated 75-78, staying with the flow of traffic, in the right or middle lane. One morning, I was slowly being passed by a new Honda Civic. I could see the Civic's bright (TOO bright) blue digital speedometer display showing "70". I was at 74 indicated, and he was creeping by me. Yesterday I received my new Garmin Zumo 550 GPS unit for use on my bike. When I turned it on as I was driving my car, it showed a 5mph difference between it's measured speed and my 530i's speedometer reading. I was not surprised, and it explained a lot, such as why I've never gotten pulled over in the BMW even though I'd gone by radar traps sometimes at more than 10 over the posted limit.

I don't know the reason for the difference, but I guess I'm OK with it because I drive slower and don't get tickets. (I seem to offset that on my bike though.) The 530i has 17" BMW Style 81 wheels, now running Viking Snow King P225/45-17's. I'll check the speed again in a week or so when I throw those worn-out snows out and put the nearly-new Michelin Pilot Sport tires back on (same wheels.) They are the same size, I'll be curious to see if there's a big circumferential difference that affects the speedometer accuracy that much. But I digress....

If you can Mike, let me know if the cyclonic separator system is the same as the crankcase breather system.

Thanks,

Ken M.

RE: M52 oil consumption?

schneller — Thu, 27 Mar 2008 12:27:02 GMT

If you drive the car briskly (80 mph highway cruising), it will use oil. 1 quart in 3500 miles isn't out of the ordinary.
Should the car use more, I'd rule out a clogged crankcase breather system before anything else.

Good Luck!

Mike Morris
Schneller BMW Performance
26 Middle Rd
Newbury, MA 01951
978.465.2002

M52 oil consumption?

KenM10759 — Sat, 22 Mar 2008 20:33:19 GMT

What is acceptable, normal oil consumption for a 3.0L six in my E39? It's just over 120K on the clock, and seems to use a quart of oil in about 3500 miles. Is this normal, high, or in the danger zone? Perhaps I'm just looking for an excuse to get a new ride, but I do love this car. ;)