The_Remora

Hey guys,

Not 928 related but has to do with timing belt (or chain?) and possible piston/valve interference in the event of a failure. I've googled this, searched Bimmer Forums (their search function is worse than here), Roadfly and various BMW related websites and didn't find this an answer to this basic question:

Does the BMW E36 325i ('98) have an interference engine? Its not even my car but my dad's. He asked me and I told him I'd search the interweb and find out, but alas my search-fu is weak tonight.

If nobody here knows off hand I will join the Bimmer forum and ask over there, although thats kind of a pain since I don't even have one myself.

Anyway if you do know, I'd appreciate the help!
Thanks,
Chris

S4ordie

Might try the OT forum. Lots of Bimmer owners there

entropy_engineering

I'm trying to remember some information from an import shop I worked at and repaired a broken chain on one. Lots of people are confused because the information from BMW. They say if it sits long enough the motor can be spun over safely because the lifters are fast bleed down type so they will absorb enough of the cams lift to not interfere. If a chain breaks while it's running the valves are toast.

entropy_engineering

Also, the service manuals say you need all these funky tools to reset the vanos (variable timing sprockets). If you study the manual long enough it's real easy and doesn't require any special tools, just a straight edge to lay across the flat parts of the cams to line up with each other.

The_Remora

Cool thanks guys. I actually did go to post this in off topic forum and remembered that my membership has recently expired and posted here. Mod should probably move this thread there so I don't clutter the 928 forum. I'll pony up and renew later tonight or tomorrow and go check it over there. Thanks for info so far.

Stan.Shaw@Excell.Net

Not 100% positive, but thought they were. I have a '96 M3.
There is a term called the "money shift", when on the track and one accidentally downshifts from 4th to 1st instead of 3rd, leading to bent valves. Very common, so at least the M3 (S52) motor is.
http://forums.bimmerforums.com/forum...d.php?t=100256

There are even techniques for preventing the money shift:
http://www.shortshifter.com/techniques2.htm

Some quick google searches find some confirming thoughts:
http://www.dtmpower.net/forum/e36-3-...ce-engine.html

The_Remora

Thanks Stan! Exactly what I was looking for

Hilton

Wow, interesting thread links Stan. Never heard the term before.. amazing that most of the people attribute it to driver error, when it seems to be a common issue only with the BMW.

Interesting comparison with 2/6 failure in 928's; here we're all pretty comfortable that Porsche oiling design is the issue. The bimmerforums thread they majority place the driver at fault, despite it being an M3 issue, not a general performance car issue. Maybe it says something about BMW drivers, rather than car design?

heinrich

yes., i was a BMW club membr and my first timing belt failure was on an M40 motor at 160km/h

heinrich

No Bubba ... if you're a moron and shift to 1st at 100mph (and yes I have) then YOU are to blame, not BMW. Try popping the clutch and foot flat on a 4-5 shift in a 944 at speed because you're used to driving a 928 ...on;ly you're going to REVERSE .. btdt... and rolling to a stop, popping a 928 into reverse because you're thinking you're hitting 1st in a 944 ... btdt. Who's to blame? DRIVER.

Hilton

Apples and oranges Henrich. Your example is driver error due to your inability to adapt your brain switching between completely and radically different shift patterns.

However its not like the BMW shift pattern suddenly changed halfway through their drive, or is radically different to other cars, or like these drivers did anything unusual in their driving other than missing a shift during a near-subconscious action that they'd performed hundreds of thousands of times before with no incident. Unless you're going to tell me all the money-shift guys had a dog-leg gearbox car as their other drive?

Good info to have - I was tempted last year to pick up an E36 M3 as a city runabout to spare the 928 from short drives (torturing a bmw motor doesn't seem as bad ). I may yet own one.. if I move to a house with space for more cars.

Stan.Shaw@Excell.Net

While the issue may be a driver error, there are contributing factors. One is that if the driver is just in a seat belt for a D.E. and the shifter is grabbed on to, while also holding the steering wheel, the driver could be pulling the shifter to the left by accident. Another is the reputed smooshy transmission mount, allowing the transmission to changed in position relative to the driver, with the same results as the first. There are solutions to both issues, as installed in my M3, but frequently the driver hasn't added harnesses or upgraded the transmission mount for a track day when the problem occurs.

Basically it is a design flaw that someone with limited skills can drive the car so fast in its stock form. Never had the money shift problem myself