July 26 2006   Story: Bryan Joslin, Photos by Author

Since the day I hopped in my 318is in California and started driving it home to Chicago, I have been acutely aware of some oil issues with the M42 4-cylinder engine that resides within it. The freckled asphalt where it was parked was the first tip-off. In the last installment of this series, I also mentioned the noisy timing chain tensioner and speculated on the likelihood of an oil pressure loss. Little did I know that the leaks and the noise shared a common cause.

As a car guy that knows better, I felt horrible about delaying what was obviously going to be a major engine service. But with limited time to wrench on my own project, I knew I was going to have to kill two birds with one stone. The other "bird" in this case was changing out the entire suspension. The car would have to be elevated for both operations, so I decided to tackle both projects at once. I even budgeted an entire weekend for both. Three weeks later, the car is back on the road.

Before I get into the perils of the engine work I'd like to talk about suspension. My car, like most other 100,000+ mile cars, was feeling a little tired in the chassis department. Ball joints and tie rods were obviously worn, and the shocks and struts had seen better days for sure. Naturally I wanted to lower the car, but with so many worn out components, it would have been foolish to simply bolt new performance parts to otherwise fatigued mounts. A total overhaul was the only real option.

BMP Design offers a full selection of OEM and performance suspension parts, and provided me with brand new control arms (complete with ball joints), control arm bushings, tie rods and strut and shock mounts. While the control arms and tie rods are standard-issue replacement parts, the rest of the components are built to a higher standard for the needs of hard drivers. The rear shock mounts feature a tapered sleeve instead of the factory's straight-through insert, seriously reducing the opportunity for failure under higher loads. The front strut mounts were upgraded to camber-correcting items that dial in an additional half-degree of negative camber, important on a lowered chassis. Finally, the rubber control arm bushings were replaced with a pair of urethane pucks.

As for the main suspension upgrades, I turned to a combination of components that has served me well in the past- H&R springs and sway bars with Koni adjustable shocks. Although adjustable-height "coilover" kits are more popular, I knew that I wanted only a moderate drop in ride height and preferred instead to have damper control. The one downside of this setup is that the rear shocks cannot be adjusted once they are installed, so a middle setting was chosen. Both the front and rear sway bars are substantially beefier than their stock counterparts, and they also feature multiple mounting positions for a little tenability.

The suspension changeover procedure is fairly straightforward. Follow the instructions in either a Chilton's or Bentley repair manual and you should have no problems. I had the Chilton manual on hand, and while it is somewhat vague and poorly supported by photography, I had no issues getting anything apart or back together. I also discovered the true joy of working on an older car that has spent most of its life in the desert; not once did I even have to reach for the WD-40!

Up front are conventional MacPherson struts, requiring a spring compressor for disassembly. The strut housing features removable strut cartridges, held in place by a threaded collar. There are two different diameters of cartridge depending on your car, either 45 or 52 mm. Mine was equipped with the larger ones, and with a bench vise and large pair of ChannelLock pliers, the changeover was quick and simple. Fortunately, I had the entire front sub-frame out of the car for engine work, so changing the sway bar over was a cinch. Although I performed this work in small stints over several days, it actually took only a couple hours to complete.

The rear springs and shocks are mounted separately, and require no spring compressor. However, it does help if you have a stout friend around to stand on the control arms while you pull the old springs out and squeeze the new ones in. I did it solo, and the procedure was comedic at times and frustrating at other. The only tricky part was snaking the old sway bar out and working the new one in. In total, this operation took around an hour with the car already off the ground.

I measured the distance from the ground to the top of the wheel openings both before and after the operations. Up front, the average height was 25.75 inches on the stock suspension and 24.5 inches afterward, for a drop of 1.25 inches. In back, the average height was 24.875 inches before, and 24 inches after, dropping 7/8 of an inch. These numbers aren't radical by any stretch, but for a daily driver in a driving environment of potholes and perpetual road construction it's rather practical. At least the extremely awkward gap between the wheels and fenders has been sufficiently reduced.

The resulting ride is decidedly firmer, but very streetable. Corners are now taken without the obnoxious listing that prevailed before. I haven't had a chance yet to test the understeer/oversteer balance dictated by the big sway bars. The most noticeable difference is the low-speed steering feel from the increased negative camber in the front.

Here are some other observations about the suspension components I installed in my E30:
· Koni is a Dutch company, and their installation instructions can be baffling sometimes. They contain no words, only pictures. If you're good at assembling Ikea furniture, you can probably figure it out though.

· H&R offers three variations of front lowering spring for the E30 chassis. Different models with different engines settle in differently over time. I chose the lowest setting.

· H&R's sway bar bushings feature a slick Teflon cloth insert, eliminating the need for nasty lubricating grease.

· The camber-correcting front strut mounts do not come with any hardware. You must transfer the studs from the original strut mounts.

Now, back to the engine work. With oil weeping out of nearly every seam in the engine, I ordered up what I hoped were all the necessary seals and gaskets to keep the black gold INSIDE the crankcase. These included the valve cover gasket, front timing case gaskets (upper and lower), and oil pan gaskets (also upper and lower). I also had a new oil pump on hand, just in case that happened to be the root of my oil pressure problems. And since all the pulleys would have to come off, new belts were ordered.

Knowing I would be doing a lot of work on the front side of the engine, I elected to remove the hood for the best access to everything. Once the hood was off, removing the fan shroud and radiator were no problem at all, leaving clear access to all of the pulleys. For the most part, this was all straightforward work, and once again the vagueness of the Chilton manual proved a mixed blessing. The only real challenge was getting the crank bolt to loosen. There is a special tool specifically for this that mounts to the crank pulley flange with three bolts, holding it in place while you turn the 22mm crank bolt. This is no easy task given the 224 lb-ft torque specification for this very important piece of hardware. I fashioned a two-bolt tool out of steel bar stock, but wasted no time in destroying it against the insurmountable resistance of that bolt. After trying numerous other workarounds, I made a new tool, but this time out of heavier gauge angle iron. Pulling against it for all it was worth, the bolt finally let loose. With all the pulleys removed I was finally able to move onto removing the timing covers and the oil pans.

At this time I decided to work from the bottom up, starting with the lower oil pan. For those who are not familiar with the M42 engine (and many other BMW engines), the oil pan is a two-piece affair. The lower portion allows access to the oil pump pickup without having to lift the engine above the sub-frame. Based on the accumulated oil at this joint, I fully expected a bad gasket. What I wasn't expecting was to see five bolts lying in the bottom. A quick glance upward revealed that the bolts had fallen out of the upper oil pan. Suddenly, it all made sense. The bolts had been drawn to the oil pickup tube and were blocking off just enough oil flow to prevent the timing chain and lifters from operating properly.

A little more research revealed that I was not alone in this ordeal. Apparently as the engine achieves higher mileage the oil pan bolts slowly work themselves loose, including any of the six upper pan bolts that reside inside the pan. Sure enough, even a couple of the upper pan bolts on the outside had dropped off as well. I looked at the lower pan bolts that I had just removed and realized that three of them were non-factory pieces, indicating that they were probably filling holes left behind from previous "jumpers." It's a wonder the engine was holding oil at all.

I was lucky- my engine was at least still operating. Others had suffered terminal engine damage from the oil starvation caused by loose hardware. Still, I couldn't help but be worried about the health of my engine's internals. I pulled the valve cover off to inspect the cams and lifters for evidence of insufficient lubrication. Thankfully, everything checked out good as new, without so much as a scuff on any of the surfaces. If the oil was getting up to the top of the engine, I figured it was a safe bet that the bottom end was getting what it needed too.

Getting the upper oil pan off proved to be a major obstacle, as it rides over the front sub-frame. The repair manuals will tell you to lift the engine high enough to clear the frame, but from where I was seeing things, it made more sense to support the engine in place and simply drop the sub-frame. It made sense, since the front suspension was already off. At one point I contemplated skipping the new gasket and simply tightening the bolts and hoping for the best, but after seeing the deteriorated original pan gasket, I knew I'd made the right call. It was a big job, but in the end the only real snag was having the steering column separate from the steering rack during the work.

Replacing the oil pan gaskets and reinstalling the proper hardware would have probably been sufficient to cure the oil leaks, but once you're in this far it only makes sense to take care of much as is practical. So the timing case covers were also removed and new gaskets fitted. After all, I had already ordered the parts, and 90% of the labor to get to them had already been done.

So it's all buttoned up and back on the road. There is still a small drip coming from somewhere, but nothing like before. The lifters are quieter, but not totally silent- at least the timing chain tensioner is dead silent. Now that these major issues are addressed, I finally feel comfortable adding some power to the mix. In the next installement you can look forward to viewing some new dyno graphs.