New Owner FAQ

Updated 03/19/2004

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Here are some ideas for new owners or owners of cars of uknown condition


Courtesy of Chuck Denson, Lars - Bend OR, Misha, Tulsa Dave, DScott, Peter Florance, Mr Coffey

  1. Read the FAQ at the top of the Bulletin Board. Make sure your posts meet our guidelines. We're a little fussy, but that's intended to keep the board friendly and on-topic.
  2. Check the ground strap. It comes from the (-) and goes to the body. surfaces should be clean and tight. Aftermarket battery cables are poor quality for the most part. If you need new cables or body to battery grounf strap, order the OEM BMW cables. They work really well. Disconnect the battery before doing anything electrical. Also, clean any other grounds you can find--particularly the cluster of wires near the front of the fuse box. Also, replace any wires that look old and/or crappy. Particularly the large-guage negative and positive cables to the battery and starter. Check all the fuses and replace bad ones (or super old ones) with ones of proper amperage. Clean the fuses holders carefully with a toothbrush or something (don't use the toothbrush after). There are also ground under the dash, in the trunk and under the back seat that should be cleaned up.
  3. Replace plugs, points (if applicable), cap, rotor and plug wires if funds permit. The correct spark plug for stock 2.8 and 3.0 motors is the Bosch Silber (silver) WR9DS. The correct spark plug for 3.3 and 3.5 Motronic (or formerly Motronic) motors is the Bosch Silber (silver) WR9LS. Both are not cheap but work much better than platinum plugs and will last much longer than Bosch Supers or other non silver plugs.
  4. If the car has sat for a while, the fuel injectors may be clogged. You can have them cleaned; but I've found if the car is running, they tend to clean themselves after a few tanks. So use a good fuel injector cleaner in the fuel tank (BG44K available at shops and some Toyota dealers is quite good). Run at least 6 tanks of fuel before making any decision about the health of the injectors. I've found the more you drive it , the better it runs - Peter
  5. Sometimes E12's run hot. Be sure it's running hot. If the temperature gauge moves around when the heater fan or headlights are switched on or off, there's a grounding problem and you can't trust the reading (Peter) Check the battery cables and engine grounds and get an independent measurement of the cooling system temperature. Read Cooling System FAQ. Bleed the radiator. If air is trapped in the system, the head will not cool itself well and you may not get proper cabin heat. Use a ratio of coolant/distilled water dependent on your climate. DScott - "Maybe "flush the radiator" and the block would be a good idea. Run clean water through it until it is clear. Replace your rad. reservoir bottle cap if it leaks or looks bad. Also, check hoses--particularly under the intake runners--these seem to rot out after a couple of decades. Refill the rad with decent coolant (50/50 mix) and (very important) bleed the system. Take precautions with the old coolant--it's poison and animals like the taste."
  6. WD-40 the hood cable at the handle and the locking mechanism (up front)
  7. Change the oil and replace with the proper weight stuff. Also, change the filter but make sure you replace the rubber ring and seat the canister properly (assuming you don't have a modern spin-on type). This is a little finnicky but worth it. The proper summer weight for most models in most countries is 20W50. Thinner oil can leak or burn easier and may cause low oil pressure at idle.
  8. E12's have great brakes. Very powerful. If the car you have doesn't have great brakes, they are not working correctly. Change fluid and rubber hoses first (Peter). If the front pads are wearing unevenly (thicker on one pad than the other or thicker on one end of a pad) you probably have a stuck piston. If so, Rebuild the calipers and bleed the brakes. Otherwise start with hoses and new fluid. Every car should have brake fluid changed every 2 years. Brake fluid absorbs water which rusts internal metal parts, tearing seals. After you've flushed your e12, take a look at the other cars in your driveway.
  9. Write with any other questions. Include your location, model, and year. The only stupid questions are the ones you know the answer to.
  10. Keep an eye out for junkyards. Rusty parts cars can be had for cheap. If you have the funds and space, they can be a great source of parts and practice surgery!
  11. Get a Haynes and/or Chilton's manual. Mr Coffey notes: "I have a Chiltons that came with my E12 and it is not of much use other than to put it under a jackstand to add about 1 1/2" height! :) "
  12. Read the technical FAQ. A lot of people have gone through the same problems. Don't re-invent the wheel! There's more detail in the FAQ's then we have time to include in web-board posts.
  13. Use only OEM bulbs from BMW. Copper colored after market bulbs do not have the right resistance and are a source of problems with particular regard to the turn signal process.
  14. Lube all hinges, throttle linkages, door strike plates, windsheild wiper linkages, etc. White lithium grease works well.
  15. Perform operational check of all lights, flashers and turn-signals.
  16. Replace all fluids if funds permit (Brake, Oil, Radiator, Tranny, differential, power steering) . Power steering fluid is Dexron II or equal.
  17. Look for cracked or split hoses by using a foamy water solution to identify vacuum leaks.
  18. Check rear differential mount for metal fatigue and possible failure. (A repair kit is available.)
  19. Clean all fuse contact points and look for faulty/missing fuses. A new set of fuses is cheap and often fixes strange problems.
  20. Check Air Flow Meter (AFM) door movement for binding. This can cause stumbling, lurching and backfire.
  21. Pre-Purchase: Suspect Rust spots; Rear shock towers, underneath front/rear window molding, trunk spare wheel well, trunk-side of rear seat sill, lower portion of "B" pillar, driver and passenger floor pans.
  22. Also look for rust just under the vent at the back of the hood. Also lift the door seals and have a look. Very well hidden and I've seen it on more than one.
  23. A good place to start is with the ignition system. Inspect the cap, rotor, points and plug wires. If the wires look suspect or if the connections are loose replace them. Also, take out the plugs and make note of how they look--clues to how your motor is running can be found here. Either clean and gap the old plugs or put in new ones. (Don't cross-thread them when you put them back--also, use no-sieze when you replace them.)
  24. Check out the harness that attaches to the underside of the fuse box (forget the name). It branches off to the oil sender, distributor, aux air valve, etc. (on 1977, 530i anyway). These seem to get knocked around after a number of years.
  25. Adjust the valves. While doing so check the oiler tube hollow 'banjo' bolts for proper torque (~ 8ft lbs I think). If they get loose, the first few cam lobes will be starved for oil, ruining the cam and rocker arms. There is an updated bolt from your dealer that has locking compound built on to it. There's a circle inscribed on the hex head to let you know it's the new bolt.
  26. Check the timing. Many of these cars are timed to TDC instead of the proper 22 degrees before top-dead-center (BTDC). It will really wake the car up. The timing marks are viewed through a small window on the driver's side (left hand side) of the transmission bell housing. There is a pointer cast into the window opening that should point to the 22 BTDC timing mark at the specified RPM (varies with models). Automatic transmission cars use a long peg (22 BTDC) and short peg (TDC) pressed into the flywheel for timing marks. The manual transmission cars use a steel ball (22 BTC) and the characters "0T" (TDC) stamped on the edge of the flywheel. One of my cars has no timing marks on the flywheel. Why, I don't know. I use an adjustable advance timing light set to 22 BTDC and strobe the TDC mark on the front harmonic balancer. There's a pointer on the lower timing case cover that should line up with the TDC marks (marked 0|T ). Timing adjustments should be done with advance and/or retard hoses disconnected from distributor and plugged. Most e12's with M30 engines should idle (with all hoses connected) around 10 BTDC. Any major difference from that may point to an advance problem.
  27. If your engine runs poorly or not at all after rebuild or head remove and reinstallation, it's possible the cam or distributor timing is incorrect. When the #1 cylinder on the engine is at TDC (compression stroke) the pointer on the front timing cover should be pointed to the 0|T mark on harmonic balance. The distributor rotor should be pointing at # 1 spark plug and the cam should be at the TDC position. Click here for a picture of the cam sprocket properly aligned. Both #1 valves should be closed (cam lobes pointing down).


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