Friday, September 7, 2007
Hood Hydraulic Lift Cylinder Replacement
I opened the hood to check fluids last weekend when I realized the hood wouldn't stay up on its own. It didn't fall quickly under its own weight so I knew that only one of the lift cylinders had failed, but given their age I decided to replace both. The units cost $34 each + $6 shipping from Tischer and arrived in a day. Can't beat that service.
Installation was simple. First I had to figure out a way to prop up the hood while I worked on the lift cylinders. A broom wasn't high enough when put on the floor so I used one of my ramps (about 6" high) along with an inverted oil drain pan (about 4") to elevate the bottom of the broom to the needed height.
To remove the old cylinders I had to unlock the clips holding each end of the cylinder to its respective mounting point. The outer edge of the mounting clips digs into a recess into the mounting rod to lock the cylinder to the car, so I used two small flat-blade screwdrivers to slide the clip up just enough to get it out of the way. With both upper and lower clips loosened, I gave the cylinder a good tug and promptly removed it.
When I removed the right cylinder I found it covered in oil and without any compression. The other cylinder seemed to have pretty good compression, but it wasn't as firm as the new cylinders, so I'd say it was a good call to replace both at this time. Incidentally, the new cylinders came with new mounting clips so there was no need to preserve the old clips but it's important to keep an eye on them because the clips can fall off and wind up wedged in one of the many hard-to-reach areas in the engine bay.
To prep the new cylinders I simply positioned the clips such that the mounting holes were unobscured and then pressed the cylinder onto the car. I twisted the cylinder accordingly to put the "open" end of the clip toward the end of each mounting rod (see the picture for the correct fit on the upper mounting point...the lower mounting point is installed in the opposite direction). This is so the extension on the clip digs into a recess in the rod and locks the cylinder to the car. I pressed the units on and the clips snapped in place. I then tugged a bit on the mounting points to make sure they were tight.
The hood now opens with a vengeance I haven't seen in years and takes quite a bit more force to close. To clean things up I used some fabric tape (similar to that used when the car was new) to secure the wires to the lift cylinder and punched out on that job. The bonus? I saved about $30 sourcing the parts from Tischer and saved $75 in labor doing the job myself.
The weather Labor Day weekend was easily the best I'd seen all year. Perfect temperature and humidity, calm winds and clear skies. I had plans to fly the Skyhawk to New Hampshire and even had a friend drive over an hour to join me. When the battery failed a preflight check, I became irritated because we're fastidious about maintenance and rarely have to cancel a flight for a "squawk" (pilot lingo for a maintenance discrepancy). But the preflight runup is designed to provide the pilot with the information he needs to make the critical go/no-go decision and last weekend was a no-go whether I liked it or not.
That adventure served to remind me that it had been over five years since I last replaced the battery in the E36. Because BMW puts the battery in the trunk away from the destructive heat of the engine bay it's fairly common to get 5-7 (or more) years out of the OE batteries, but that's not to say a five year old battery is the same as a new one if it gleefully turns over your engine every morning, however.
First of all, all batteries lose ampacity over time due to normal and unavoidable chemical processes, so older batteries simply don't provide the same energy storage as new units. Secondly, and perhaps more importantly, individual cells within the battery can weaken to the point that the battery will no longer take a full charge. If this occurs, the vehicle's charging system will overcharge the battery and hasten its demise while at the same time it places an unnecessary load on the vehicle's alternator. Given the cost of parts and labor to replace an alternator and the potential for physical damage to the car as a result of battery leakage (just because it's "sealed" doesn't mean it will always be so), it's generally better to replace the battery before trouble sets in.
The E36 takes a Group 92 battery but very few aftermarket manufacturers make or stock Group 92 batteries (or so I found). The E36 body can also accept a smaller Group 48 or 91 battery (originally specified for 318's) but those smaller batteries usually sacrifice some ampacity. Since I doubt BMW put a larger battery in the 328 just for fun, I decided to go with a Group 92. That meant buying another OE battery.
I emailed Jason at Tischer and found that they consider even AGM (so called "starved cell") batteries HazMat, so they could not ship one to me. I placed calls to my local dealers and found widely varying prices. Circle BMW in West Long Branch, NJ gave me the best quote so they earned my business. As luck would have it, they are located a couple miles from my office, so I went over at lunch yesterday and picked up the new unit. When I got home, I took the Battery Tender off of the E46 and put it on the new battery to top it off overnight so as not to put a heavy load on the charging system when using it to start the car the first time.
To remove the old battery I removed the vent tube from the front side of the battery and set it aside. Then I followed the same technique recommended to disconnect the battery for any electrical system maintenance -- I removed the negative cable (black) first, followed by the positive (red) using a 13mm socket. After I hauled the heavy battery out of its compartment and set it aside, I decided to clean up the area first with some moistened paper towels to remove the dust that had accumulated over the last 10 years. Then to ward off any corrosion I sprayed the floor compartment with a couple light squeezes of WD-40 and wiped up the excess with a paper towel.
To install the new battery I secured it with the clamp and then replaced the vent tube, followed by the positive and negative cables (in that order). When I reattached the negative cable and heard the CD player start to cycle through the discs, I knew I was in good shape. After the battery was reconnected I entered the unique security code into the radio as well as the time and date into the OBC, and reset the one-touch up power window sensors by pressing and holding each window up button for approximately a second after the window fully closed.
Shopping around and leveraging my BMWCCA discount saved $50 in parts while doing the job myself saved $75 in labor.
Mileage: 149000, Parts: $190, Parts Saved: $80, Labor Saved: $150
Thursday, September 13, 2007
New Windshield, Take Three
One of the things I love about summer is that when driving home westbound (late in the day as usual), the sun is typically high enough in the sky that it's above the top of the windshield and out of my line of sight. Unfortunately, since we passed the summer solstice some three months ago the days have become shorter and my drive home of late has forced me to contend with a very bright sun low on the horizon.
Most of the time there is at least some high cirriform clouds that tone down the glare, but last week while I drove home with beautifully clear skies I found myself absolutely blinded by the sun. I was wearing sunglasses at the time but they had little effect. I tried refocusing my eyes and shifting my head left and right in a futile attempt to obtain better vision but realized that four years of sandblasting of the windshield on the daily commute had taken its toll. I quickly concluded that it was time to give my insurance company a call and get the window replaced again.
The installation crew from DuRite Auto Glass showed up today around mid-morning and managed to replace the glass in about an hour. I didn't bother to take any pictures because I already covered the subject in detail not once, but twice. About the only thing that's changed in the procedure was replacement of the manually-operated caulk gun with a motorized unit very similar in appearance to a battery powered drill. The tech can use the variable speed of the unit to change the flow rate of the sealant so they can fine tune the size of the bead or the speed at which they glide over the window frame. Very slick tool.
Many months back I replaced the air inlet cover at the base of the windshield but forgot to install the four clips in the center of the piece that keeps it snug up against the windshield. Since the crew had to remove the cover to replace the windshield I took advantage of the situation and replaced the clips. I figure that's one less job to consume my ever-decreasing free time.
While I had the tech on hand, I asked him whether it would be possible to replace the dried and cracking trim kit surrounding the rear window without actually replacing the window and he told me it wasn't possible because the trim typically bonds with the sealant applied at the factory. I'm not sure if I want to spend any money replacing that window, but the trim does look like garbage. Perhaps next year after more pressing issues are addressed.
Since the car couldn't be driven for a couple hours after the window replacement I pulled the E46 out of its lair on this beautiful early fall day and headed off to the salt mine.
My comprehensive deductible is still $100 (yea, I pay extra for that, but it's paid for itself several times over) so that's what the job cost me.
Delayed Cold Start
The BMW M52 engine has always been reliable and smooth-running. The one thing that I could always count on was the engine firing on the first couple of cylinders. A quick flick of the ignition key was all that was necessary to bring the engine to life. Unfortunately, around the time our corrupt government mandated the contamination of our fuels with the corporate welfare to ADM otherwise known as Ethanol, the engine started to take longer to fire and then it would tend to stumble for the first few seconds before stabilizing into its characteristically smooth idle.
Lately, as the weather has turned slightly cooler in the mornings I've noticed that the engine now turns over but doesn't fire until I run the starter for about 2-3 seconds. I was overdue for a can of "fix-it" so I went to my dealer to get a bottle of fuel system treatment and chat with my technician. He told me that the old treatment (translucent white bottle) has been replaced with a black plastic bottle closely resembling the retail packaging of Techron. This new stuff is made by the same company and it's supposedly "compatible" with E10 fuels.
Earlier this week I ran the gas gauge down to the red zone and then dumped a bottle of the cleaner in before fueling. The next morning the starting problem was worse, not better. Of course, I'm not talking about a real "hard starting" problem like some people seem to have with these cars in that I don't have to crank for 5-10 seconds or crank multiple times to get the engine to start, but it's just not running the way it did a couple years ago. And yes, I know the engine has almost 150K miles on it and I shouldn't expect it to run like it was new, but I just hate beating on my starter and battery for any longer than strictly necessary.
For now I'm still in the dark as to what's causing the problem but I have my theories and they will be explored over the coming months.
Mileage: 149151, Labor: $100
Thursday, September 20, 2007
The inspection sticker on the E36 was slated to expire this month so I decided to get up early and get the vehicle inspected today to avoid the typical end-of-month lines. I stopped by the dealer first to ask my technician to connect the GT1 and check for codes, just in case it had stored a code and not tripped the check engine light...as it had when it complained about catalyst efficiency late last year.
The goal in this case was to eliminate any possible reason for the state computer-based inspection process to fail me, as I don't know what the state computers consider a "passable fault" and a "failure fault". My technician suggested that the way OBD works is if the check engine light is not illuminated the car will pass inspection. I felt bad adding yet another item to his "run-queue" (the man runs around like the proverbial headless chicken in the morning, let me tell you) but five short minutes later I had my report -- no faults stored.
I threw my tech a tip to say thanks and headed off to the inspection facility where it passed with flying colors. The only notable difference between this and every other inspection the car has received was the compliment from the inspector about how clean the car looked. I guess they don't see too many of these older BMWs in the same condition.
Cold Start Issue Persists
While talking with my tech today I asked whether they had seen any recent flareups in problems relating to cold starts. He said he had seen quite a few cases caused by a failing check valve in the fuel pump (apparently they're susceptible to the alcohol in the new E10 contaminated fuels), but that was about it.
Not five seconds after my tech finished his sentence one of the other techs came up to discuss an '02 3 series that had been sent in for the same problem except the owner reported the engine wouldn't fire until he had cranked it for at least 25 seconds. BMWs solution to that problem was wiring related and from the looks of the service bulletin totally unrelated to my issue...especially considering my car starts just fine....it just takes a couple seconds of cranking during a cold start vs. immediate warm starts.
My tech suggested that it could be the check valve in the pump. I told him I'd already considered that and had tried to use the ignition key "trick" (to no avail) to make sure the fuel rail was pressurized. I cycled the key three times with about 5 seconds spent in position 2 each time, but he pointed out that one cycle of the key might not be enough to fully repressurize the rail and I'd have to wait about 2 minutes between key cycles in order to make the pump turn on again...otherwise cycling the key would have no effect on the pump and the pressure might still be too low.
To figure out if fuel pressure is the problem, I need to attach a fuel pressure gauge to the schrader valve on the end of the fuel rail, measure the pressure immediately following shutdown and then again after the car has sat overnight. If the pressure is noticeably lower, it's very likely either the check valve or a leak in a hoses somewhere. Which brings me to say that many techs, including Mike Miller of BMWCCA recommend wholesale replacement of BMW fuel lines every 10 years...and that wisdom was based on many years of running pure gasoline...not the alcohol blended fuels we run today. One of the reasons why alcohol is prohibited for use in standard certified aircraft is its deleterious effects on rubber, so the bottom line is that until all fuel lines in the BMW are swapped out with alcohol-compatible lines (assuming such alcohol-friendly rubber even exists), they are suspect.
For now the problem isn't enough of one to warrant a tizzy but I do plan to pick up an inexpensive fuel pressure gauge and figure out the extent of the job necessary to replace all rubber fuel line components.