And with that, let's get back to the project thread. Thank you gentlemen for your thoughts on the tire question; it's not quite oil thread level, but certainly debate worthy. However, let's leave that topic for the time to other threads dedicated to the question.
Since the fuel tank was full of rubber debris - or derbis, as they say in Minnesota - I wanted to fully clean it before reassembly. I picked out about 1/2 of a cup's worth with shop towels, but there was a good couple tablespoons left that were being recalcitrant. I let it sit with the filler cap assembly removed for 72 hours to allow the remnants of the
gasoline turpentine to fully evaporate, then exorcised the last of the rubber demons by dint of much shaking and the illicit application of my wife's vacuum cleaner. On a side note - it probably would have been better to wait on that last till she'd left for work, but that's another story.
With the rubber removed I set about re-assembling the pump assembly. Getting the sock filter fitted to the end of the fuel pump (over the pump mounting grommet) was a challenge, but with patience and some slight trimming of the rough edges of the grommet with a razor blade I was able to declare victory at last.
The fuel rail was still full of the crappy old gas, so I popped off the return line and gently blew it clear from the input end. More yellow gas came out, but now I felt it had at least a shot at getting some clean fresh go juice into the injectors. I also removed the flapper from the gas cap assembly prior to reinstallation, might as well while we're in there. The tank vent line was already correctly routed and the crankcase vent capped. Score one for someone along the line paying attention.
One more sidebar: The previous owner was kind enough to pass on his service records, which showed the replacement of the fuel pump and mount in 2012. The replacement was performed at Denver BMW, and I'm exceptionally disappointed in the quality of their work. Not only was the fuel sump full of pieces of the old mounting grommet, but the sock filter was not actually fitted to the pump AT ALL. It was just sitting in the sump, completely detached from the pump assembly. I know that it did not fall off, due to the difficulty involved in getting it fitted to the pump. It's very solidly on there once mounted correctly, it would take some significant effort to remove. The dealer tech apparently had the same issue with installation and went with the F--- it approach and just stuffed the whole works back in un-assembled. On top of a sump full of rubber bits just waiting for their chance to get sucked into the new pump.
This is exactly why I work on my own machines. Well, that and the fact that they charged the PO over $1200 for this abominable excuse for service. This bike will never be serviced at that establishment. I would expect better from a BMW dealership in a major city, but that's apparently naive.
Rant off.
On a happier note, the battery was also replaced in 2012 with a fresh 19 amp hour BMW battery. Although it had sat uncharged since, it accepted a slow trickle charge and held steady at 12.24 volts over 48 hours off the charger. There's one less part to buy.
After installing the fuel pump assembly back in the tank and plugging everything back in, I flipped on the key hoping to at least hear a whir out of it. No such luck, zero noise. I unplugged it again at the harness and used a test light to check for voltage while cycling the key. Still nothing.
A consultation of the wiring diagram seemed to indicate that the fuel level sending unit may be involved with the pump wiring to some degree, so I figured what the hell - I'll put some gas in and crank it. Never know, and I've spent way too much time in the past trying to track down a problem that wasn't actually a problem. For all I knew, it needed something in the tank or to be cranked over to actually run the pump.
With some trepidation involving the thought that I might just be taking it back out again, I poured in two gallons of premium and waited a couple minutes.
So far so good. No leaks. Check all the connections, then check 'em again. OK, it's go time.
Key in ignition, turn on, confirm trans in neutral, and push the little green button. Crankage! Guess that old battery still has some moves. And best of all, I can now hear the fuel pump whirring happily away as it pushes the air out of the lines and replaces it with sweet and tasty gasoline.
Couple more crank attempts (don't want to overwork the starter) and no sign of combustion. Ummm...let's think about this. Hey wait, what's this lever on the left bar? Choke??? I thought this was injected...
A quick Googling revealed that the "choke" is more a fast idle, which come to think of it I have seen on other FI bikes. The last couple I'd owned hadn't had it, so it hadn't occurred to me to look.
Ok, fake choke on and let's crank that sucker again. This time we get a couple pops, then a couple more, then...
...a self-perpetuating combustion cycle! :2thumbup:
It's running rough, two out of three cylinders are going and the third is trying but mostly just popping. Ok, shut 'er down Harvey let's look at this.
The plugs looked oil fouled and generally dirty with one being slightly more so than the others so we'll start there. A quick trip to the local auto parts store produced three NGKs of the proper variety and a quiz from the counter tech on why I needed THREE plugs, when all motors should have an even number as the good lord intended.
Home again with the new plugs and whoops...they don't have those cute little nipples on the caps, just a threaded rod. :bang-head: I hastily pilfered le boxe de la shiite, and came up with two but not three threaded caps. Well...mebbe I can clean up the best looking of the Bosch plugs. I really want to see if the new plugs make a difference, and I'm not excited about driving back to the parts store just now.
I cleaned up the best of the original plugs and installed it in the center cylinder, on the theory that I'll remember which one it's in when I go to change it with the correct NGK plug tomorrow. The two properly nippled (I never thought I'd type that sentence) plugs were installed in the outside cylinders, and we're ready to go again.
One light touch of the wake-up button and holy rampaging elephants in Africa - we're running! And smoothly at that.
The choke was still on (would not idle with it off prior to the plug replacement) but that was quickly dispensed with and it settled down to a smooth idle. I let it run for a minute, then shut it down to complete reassembly. (I've learned over the years that if you fully reassemble anything prior to testing it, you are damn near guaranteeing yourself that the fates will align to make you take it all apart again. That is the truth right there, gentlemen.)
Speaking of taking it apart again, the seat latch rod had fallen down into the depths beneath the battery at some point and this necessitated removing the Motronic box, carrier, and battery for a 4th time (don't ask about the others) to rescue it. But at long last everything was back together, triple checked, and it's time to ride.
Not far of course, but a victory lap around the condo loop seemed in order so off I went.
Needless to say I didn't get up to any shenanigans, but did shift 1-2 and back a few times in the course of my excursion and everything felt good. There is a brief stumble off idle if the throttle is addressed with purpose, but I suspect that will dissipate with mileage and some fuel cleaner. Getting that third plug updated surely won't hurt in this regard either.
The only other tidbit to address was the altitude circuit. Although Denver is (famously) over 5k feet above sea level, no jumper plug was installed. I rectified this by snipping the wire and crimping on a set of spade connectors; far from an elegant solution, but it gets the job done until I source an OEM accessory switch for the handlebar switch block and route the wires up there. I like the idea of making it easily switchable for mixed-altitude rides. Side note, if anyone has a line on a switch that will fit cleanly in the OEM position where there are currently several switch blanks (next to the ignition switch), I'd be much obliged.
That's all for now; I'm out of town for most of the week on business, but hope to get on the road in short order following that.
Thanks for putting up with my ramblings, and I'll keep updating here as things go along. I enjoy writing down what I've been doing, it's a way to obsess about the cycle even when I'm not actually interacting with it and I like to think that chatting with other motorheads keeps me from torturing my wife with endless happy exclamations involving valves and rotating mass and sundry other topics which I've a knack for inserting into our conversations.
Till next time...
PS: By all means, let's have a "how old is too old" tire debate thread somewhere. I'd love to jump into that conversation - I'm very opinionated - but want to keep my project thread somewhat on topic. Only somewhat though, so please comment away as the desire strikes you.
