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Friday, April 18, 2014

Doug's Domain

Doug Vetter, ATP/CFI

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Sunday, March 11, 2012

Early Spring Service Part 1

When I opened my maintenance schedule worksheet and plugged in the odometer reading last week I saw red. And no, I wasn't angry (this time). Instead, I was merely surprised at all the routine maintenance that was past due and highlighted in red, including an oil service and bottle of Techron for the fuel system (1500 miles overdue), engine air filter (5800 miles overdue), Microfilter (1300 miles overdue) and spark plugs (6600 miles overdue). So I decided to run over to the dealer yesterday and pick up all the parts necessary to do that work today.

Knowing that BMW has historically stocked parts from two spark plug suppliers (Bosch and NGK) I asked the parts guys for the NGK versions I've been using all along. They told me that both part numbers have been superceded and it appears that BMW now provides only NGK plugs made in Japan. I've noticed a lot of parts consolidation by BMW lately so this didn't exactly come as a surprise.

I pulled one of the NGK plugs out the box to find that it was equipped with quad electrodes. I don't remember my last set of NGKs having quad electrodes and I do recall hearing of problems with the Bosch aftermarket quad electrodes, but it's hard to argue when this is the only part BMW supplies. When I saw the price I started having flashbacks to my bouts with aircraft parts prices -- plugs are now $18 my cost or $22 retail. Fortunately I don't replace spark plugs that often or I might be inclined to find a cheaper source. Plus, as I've said before, BMW engines can be surprisingly finicky when it comes to plugs so I'm not about to sacrifice my smooth idle to save a few bucks in any case.

Once at the garage, first up was the engine air filter. As I've indicated before I tend to pull the filter every few thousand miles and tap it on a clean spot on the garage floor to remove all the dust and grit it tends to pick up. This probably explains why my oil analysis reports always indicate low silicon. But one thing that tapping the filter clean will not do is remove the finer particles that the filter media traps so this explains why BMW recommends replacement every 30000 miles. The job is one of the simplest on the car as long as you remember to tuck the pink foam fully into the plastic cassette before pushing the inner part of the cassette home, and sliding the cover closed.

I've got the microfilter job down to a science now so that was little more than a 10 minute job. I continue to be amazed at how well these filters do their job, as they are typically dark gray by the time I get around to replacing them. I must admit to taking pleasure in changing the microfilter now because it results in tangible proof of what it's kept out of my lungs, and in the case of the small leaves from one of the trees in front of my residence, what it has managed to keep out of the car's ventilation system as well.

Unfortunately, I started later in the day than I originally planned so I ran out of time and decided to postpone the oil service and spark plug change until next time. Till next time...

Front End Overhaul Update

While at the parts counter picking up the spring service necessities I decided to order a few more parts needed for the front end overhaul. I didn't have my list handy but I did remember that I needed engine mounts so I ordered those along with the mounting hardware. And since every BMW this age seems to go through the really annoying "spinning ignition lock" problem, I ordered a new lock body, coded lock cylinder, and ignition switch I expect to replace when I pull the steering column to replace the lower bearing. The lock cylinder will need to come from Germany and I tend to pay for all the parts at once, so I expect to drop about $475 in a few weeks.

And speaking of the steering column, through some research I learned that the fracture bolts are M8x25. Contrary to popular belief they are nothing special, metallurgically speaking. They are called "fracture bolts" not because they fracture at some particular crash load, but rather because the heads are designed to break off as they reach proper torque for security reasons. Of course, the entire design was created prior to EWS and the value of the bolts on EWS-equipped vehicles like my 1998 vintage is questionable at best. Even if a thief were to attempt to go through the hassle of pulling the bolts on the lock body, the car will not start without a properly coded key in proximity to the EWS ring antenna. So simply to make my life easier now and potentially in the future, the plan is to remove the fracture bolts and reassemble with garden-variety grade 8.8 M8x25 socket cap head bolts so I can use a common allen key to tighten them. My guess is they will be less expensive than the BMW bolts too. Time will tell.

I also realized this week that I would need to add another special tool to my arsenal to complete the front suspension overhaul -- an engine support. I wanted something mechanical as opposed to hydraulic for the same reason I don't work under cars supported only by a jack: hydraulics fail. So that led me to the cross beam type supports used by the dealer techs for this job. I decided to check with Baum Tools and found their model 10-222A. The problem? They wanted $430 plus shipping. I'm all for buying quality tools, but there was no way I could justify that kind of expense for a tool I expect to use once in a blue moon.

While browsing Eppy's catalog I found an American Forge & Foundry branded unit that appeared to be nicely adjustable and well built. Similar versions sourced under different names found favor on the forums so given the positive experience I've had with my AFF jack I decided to throw down the $125 and familiarize myself with the unit before the "big day".

Mileage: 219285, Parts: $211, Parts Saved: $50, Labor Saved: $165, Tools: $125

Friday, March 16, 2012

More Front End Overhaul Parts Arrive

Last week when I ordered the parts for the ignition lock I assumed that it would be at least a couple weeks for the lock to be coded but everything showed up in only a couple days. The parts guy confirmed that the lock was coded here in the states so that explains the quick turnaround.

The mounts are pretty much what I expected which is to say that the rubber is in a lot better shape than the existing mounts. Based on my experience with similar mounts used in aircraft I expect the new mounts to ever so slightly improve the vibration characteristics of the engine. They are not cheap ($80 each) but they will be one less thing I'll need to replace come engine overhaul time.

The lock cylinder, lock body, and ignition switch are being replaced simply because they have been actuated countless times and are subject to a very annoying failure mode. The labor required to replace them is shared with replacement of the squeaky lower steering column bearing so it makes sense to swap the parts now rather than when the key decides it wants to turn 360 degrees and not start the engine -- or worse, not shut it down. The parts weren't exactly cheap, but like most preventative maintenance their purchase requires a long term view.

And just so I don't get a bunch of mail about the subject -- tritium keychains are available onilne, but be aware they are not entirely legal to import into the US. Also note that I have measured the radiation emitted from this unit and it's about four times background...pretty insignificant in the grand scheme of things, but stuff that in your pocket at your own risk. On the upside, the half-life of tritium is 12 years so the keychain will produce usable light for 20 years or more. I've had this for more than ten years now and it still glows nicely.

Mileage: 219555, Parts: $476, Parts Saved: $110

Saturday, March 17, 2012

Early Spring Service Part 2

With temperatures in the 60's and sunny skies, today seemed like a good day to finish up my early spring service by doing an oil service with oil analysis and spark plug replacement. I got both jobs done in less than two hours and both went about as smoothly as one could expect. Dare I say it, but this is old hat at this point.

Although I am concerned that the extra time on the oil will naturally inflate the oil analysis numbers, I skipped the analysis last fall and do need to keep an eye on the progression of the lead wear issue. The last thing I need is to start grinding away at a bearing and have a rod blow through the block. I really would like to overhaul my own engine rather than be forced to rely on an unknown core when the time comes, so that means some due diligence on my part. I plan to send the analysis out this week.

When it came time to do the plug service, I instinctually removed the covers for the nuts that secure the fuel rail cover (that's why they're removed in the picture) but I quickly speculated that I could remove the engine head cover without pulling the fuel rail cover despite the fact that they overlap a bit, particularly in one location near the front, and that turned out to be the case. That saved me all of a minute of work but life is short, so faster is better.

After I removed the coils I brought the compressor up to pressure and blew out the plug holes. As expected they were perfectly clean and dry to start with but it never hurts to play it safe. The old plugs loosened with a lot less drama than they did last time. This may be because my technician tightened the prior set a bit more than I do but I can't know that for sure. BMW's spec is 22 ft*lbs (dry fit, no anti-seize), so that's what I used to tighten the new plugs before buttoning everything up and turning the key to test my work. The engine fired on the first cylinder and settled into a very smooth idle. Pickup below 4000 RPM seemed to be a bit better too, but it is probably just in my head. Spending $100+ on new plugs will tend to do that.

(Image: Blackstone Labs oil analysis report on 3/22/2012 at 219585 miles) Incidentally, plugs are a good indicator of the state of the engine if you know what to look for. Generally speaking, plugs should be dry with a slight white tinge to the normal and expected light carbon deposits on and around the electrodes. One big red flag is wetness that does not evaporate, which indicates oil control ring wear; something that must be monitored on an engine this old. Another red flag is heavy black carbon fouling or very white and heat-damaged electrodes, which usually means mixture control problems. However, while I might expect to see this kind of fouling on an old carbureted engine or perhaps an engine with forced induction and a custom tune, it is highly unlikely to occur on a stock BMW engine for the simple reason that the DME can detect misfires and cut off fuel to the affected cylinder(s), as well as tightly control the mixture by monitoring the oxygen sensors in real time.

I found the plugs in good shape across the board, which tells me that all the cylinders are wearing consistently with good oil control. These plugs had more mileage on them than the set I replaced in 2007 and yet appeared to have held up better. Based on their appearance I would normally extend the replacement interval to 80K or more but as I've said before there are other things to be concerned about here, including valve cover gasket leaks and overall engine health. Thus it is always better to get your eyeballs "inside" the engine more frequently so my plug change interval will remain at 72K miles or roughly half the expected lifespan of the valve cover gaskets.

Now the fun part. When I combine the labor savings from Part 1 with the 2.0 hours of labor required for the oil service and plug replacement in Part 2, I'm looking at a total labor savings of $421. The parts savings of $50, while not as impressive, brings the total DIY dividend of this project to $471. My out of pocket cost again? $211. Total time out of my life? Three hours. DIY: It's like vitamins for your wallet™. :)

Next up: swapping my winter wheels and tires for my summer set.

Update 3/22/2012: I received the oil analysis today and the results were predictable. Lead is up again, but I think most of the increase can be attributed to the longer oil change interval and the possibility that oil changes in March skew the numbers due to all the cold winter starts which are known to be bad for engine wear in general and bearings in specific. In any case, I doubt 16PPM is anything to be concerned about right now but that will change, of course, if lead spikes from this "new norm". Next oil service will likely be in mid-summer.

Mileage: 219585, Labor Saved: $256, Labor: $25

Sunday, March 18, 2012

Summer Tire Swap

When I installed the winter tire set last fall I knew full well they were not in particularly good shape, and I'm not just talking about the depth of the tread. The front tires had developed a really annoying rhythmic growling noise at low speed reminiscent of a wheel bearing failure in addition to the roaring noise at high speed typical of all snow tires. And thanks to the communicative BMW steering system I also felt and heard a periodic sound most evident at low speed while turning that anyone else would have likely attributed to a screw or nail in the tire. In short, the tires were shot, but safe, and I needed to save money so I reluctantly returned them to service.

(Image: E36 side view with PS2s returned to service March 2012)Fortunately my bet on these old, worn out snow tires paid off. We did not have a winter season, or at least a traditional one. Other than the early snow that caused me to put the tires on in the first place, we received at most an inch of snow one day, and flurries on a couple other occasions. That was about it. So, although I normally wait until the first week in April to install my summer tire set because the chance for a snow storm is pretty low by then, given the weather so far this season and the forecast for 60's in the coming weeks I decided to swap the tires a couple weeks early.

The process went pretty much as expected, save for one thing. As I performed my usual inspection of the front end I found both left and right side foam shock absorbers (what BMW calls the "auxilliary shock absorbers"), broken into several pieces, barely clinging to the strut rods. That's not good because now there is nothing to prevent these tired struts from smashing into the upper spring perch and carrying damaging loads into the strut tower. The condition of the absorbers tells me that this is a very real concern as they have obviously been compressed too many times.

One upside is that the front brakes, while quite worn, appear to have enough life left in them to make it to June when I expect to pull the car out of service for the long-overdue overhaul. That means I will be able to put all new brake parts on the car rather than screw around with a bunch of old parts on what will hopefully be a near pristine, powder-coated front end.

The test drive with the PS2s was predictable: perfectly quiet at all speeds, neutral and exacting steering, and of course, on-rails handling. All I could think was "wow...my BMW isn't a truck with bad bearings after all". The plan now is to deliver all the wheels to a repair facility in eastern PA to have them dial indicated, straightened if required, and refinished before I install a new set of winter tires to ready them for next season. And yes, I'm planning to install another set of Winter Sport M3's. They're not bad tires...so long as you don't run them for more than two seasons or roughly 12K miles.

The tire swap took a couple hours, but that was because I had to haul tires and tools between my two garages, so I'll call this one hour labor saved, or $128.

Mileage: 219600, Labor Saved: $128