Part 2 of 3 of my long post.

More E28 look-for's:

3) Oil and Oil Leaks

• Visually, 'fresh' oil will appear a clear brown, as you know. Black just means old, any cloudy or white means water, which is very BAD, 'bad' being defined as like crossing two anti-proton streams resulting in the destruction of the universe as we know it.
• Check under oil filler cap: there should be no cloudiness, and gives you an idea of internal cleanliness (which is good).
• The owner's manual says it is 'OK' if the oil pressure light comes on 'at times', like idling when hot, but should go out when revved. Drives me crazy if it comes on at all!
• The oil pressure sender is a frequent leaker. The leak will track down the side of the engine and drip off the lowest point of the bell housing, so don't confuse it with other potential problems.
• The pan gaskets occasionally 'creep' out of their space and self-destruct. If you go in to replace this on a high miles motor you intend to keep, replace the oil pump (and probably the sprocket) at the same time. $150ish, and well worth it. 4) Other Engine Compartment Stuff
• All fuel lines are suspect by 100K - especially the short hank to the cold start injector at the lowest extreme of the intake manifold, for some esoteric reason. Don't use cheap stuff! Buy the BMW 8 x 13 mm stuff from one of many sources.
• Vacuum leaks are a major hassle. Prime symptom is rough idle, flat spots at mid revs, may also be fuel pressure regulator. Do easy candidates first: put an o-ring in one of the grooves in the dipstick top. Put clamps on the hoses to the valve cover and idle motor (if E28). Replace the hard-as-rock hoses in general. Replace the fuel injector o-rings.
• Look at the brake fluid. Black is _bad_, but at least means it wasn't being topped up each week (see 'slave' discussion below). Color of the brake fluid is a very good indicator of the general tenor of the maintenance regime for the car. If it is black as pitch, indicating it is _not_ getting the yearly replacement the anal-among-us so lovingly do, check more closely for all the other maintenance opportunities.
• Lots of things can make this baby idle rough; already mentioned vacuum leaks. Mucho covered in FAQ's. Best I have seen is by Sam Lin <Sam_at_cmdexsvr.cmd.com> for a copy.
• Plug wires are a 100k consumeable in my book. Cleap insurance, can help several marginal symptoms, lotsa sources, $80ish. 5) Tranny and Clutch
• No experience with the 4-speed auto, so no comments.
• The Getrag 5-speed should enter all gears smoothly - they are not especially prone to synchro failure in normal operation (i.e. not auto-x'd) but most are 'notchy', kinda hard to push into gear, especially when rev's not synched, but easily improved by putting in Redline MTL tranny oil.
• Every 100K+ Getrag I've seen leaks. From the rear is OK but messy - shift shaft seal fails, soaking back of tranny. Output shaft seal weeps, no major heartache. Seam between front and rear half of tranny case weeps, wets bottom of tranny, but no sweat. Saving the best for last: If there is oil (not brake fluid, see below) coming out of the drain hole in the bell housing, either the tranny front seal is leaking, (likely) or the engine rear main (possibly). This is _bad_ (see definition above) because the clutch is not designed to be oil-bathed, and will tend to chatter and fail. Seals are $5-$10 each, clutch trio (pressure plate, clutch disk, throw-out bearing) are $300ish. All quite doable, but considerable labor, dropping exhaust, removing driveline.
• Clutch pedal should depress smoothly, although with a lot more force in the 535i than the 528e or a 3-series. Should not hang up on either the upswing or downswing - that could be broken 'ears' on the throwout bearing.
• Stick your fingers under the forward edge of the dash sound cover just above the brake pedal and feel for wet, and smell your fingers - odor of brake fluid means the master is leaking.
• Also check for clutch master cylinder flex to one side when the pedal is depressed - the pedal bracket mounting the master cylinder fatigues and cracks, allowing the master to move around. Time-consuming to replace, but not hard.
• If brake fluid is leaking out of the drain hole of the bell housing, the clutch slave cylinder is leaking - very common, but cheap and easy to fix. Smell it to distinguish from oil, but bear in mind that you could be getting both. Another tip-off for this one is really clean brake fluid, from someone topping it up as it coats their garage floor. Another symptom for the slave being bad is that the clutch disengages very close to the floor, or the pedal will not return.
• While you're down there, check that the rear tranny mounts have not gone to mush, they do that. Check the engine mounts too; check for cracks in the top, especially on the right.
• Many of these beasties have developed a lot of play in the shift mechanism: worn shifter bushings, mushy rubber mounts on the shift pivot mounting plate. I greatly enjoy the result of the Metric Mechanic short-shift kit. Stock shifter bushing parts will cost you $35-$60 at a dealer, MM shifter $200, ACS shifter $800. Or BL/SS. No affiliation.

end-o-part-2. Larry F.

Larry Franks
Issaquah, Washington
'86 535i x 2
'83 245 GLT (Swedish iron)