Interesting Work on an E30 BMW 325

Whether it’s the E30 325, 325e, 325i, 325ix, 325es or 325is, they all use all the same wonderful M20 engine … with the caveat that if its timing belt breaks, the valves can impact the pistons and severely damage the engine.

Perform enough preventative maintenance on the timing belt, and the risk of such a problem is low.

Back325For the last 12+ years, I have owned a delightful E30 1987 BMW 325.  It recently got a big tune-up and some drive shaft work done, and I lent it to a friend who drove it for a few months.  She handed it back to me, and I drove it from Tucson, AZ to … well, about 80 miles south of my shop in Fallon, NV when the clutch gave out in the middle of the night on highway 95.  The clutch was by then slipping merrily, warning me of its impending failure, but I’d hoped I could limp it all the way to my shop before the clutch gave out but … no such luck.  A clutch replacement was due.

I ruminated on it for a year or so.  I hate working underneath a car.  It basically consists of transferring the grime and dust from the underside of the car into my eyes and onto my face. Then, a few fasteners fall into my eyes, and a few parts fall onto my face.  If I lift the car high enough to not feel cramped, then the stakes go up too because whatever falls off next has a lot of energy, and my feet become the next target.

I used to work in an auto manufacturing facility. I observed how the engine, transmission, steering, front suspension and front hubs are all mounted on the front sub-frame. When the build the car, they lift all that up, as a unit, to mate with the car.

So, for this car, my shop took this approach.  We performed the process in reverse first.  A local muffler shop removed the exhaust and drive shaft, and then my shop detached the various fasteners, hoses, wires etc. that connected the front sub-frame assembly to the rest of the car.  Next, we put a gantry over the car and lifted the car body up, away from the sub-frame.

gantry01

That allowed us very convenient access to the engine and transmission.  Normally, to split the transmission from the engine requires some special vocabulary, but in this case, it wasn’t needed.

Normally, to replace the timing belt with the engine inside the car makes for a cramped work environment, with either of the two radiators, coolant or a/c, being just a few inches to the front of the action. With our new arrangement, there were wide open spaces to work in.

engine01

The things that we ended up replacing were intended to make the car very reliable as to typical points of failure:

  • Timing belt
  • Timing belt tensioner
  • Water pump
  • Both large coolant hoses
  • Belt that drives the alternator and water pump
  • Belt that drives the power steering
  • Belt that drives the a/c compressor
  • Clutch disk
  • Clutch pressure plate
  • Clutch throw-out bearing
  • Clutch pilot bearing

Additional items I might be tempted to swap out in future such situations are:

  • Alternator brushes
  • Shifter hardware
  • Front shock absorbers
  • Spark plugs

Enjoyable project! And I might soon be driving an E30 that I can cheerfully shift at the red-line without having to baby the engine or clutch.

This project also reminded me of how many things, large and small, can and do break during a project such as this, so if you are experiencing the same thing, and you need used parts, please contact us.

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