Monday, September 28, 2009

5-speed transmission road trip

Alright, I am back home in San Francisco.  The 5-speed transmission swap went absolutely smoothly and I made it back in record time.  Just kidding.

I definitely had a plan and alotted a significant amount of time but the project nearly wound up a disaster.  In fact, it would have been if it wasn't for the huge amount of help and support from my good friends Jason, Mira, Eric, Seth, and Brant.

The basic idea was to fly up to Jason and Mira's house in southern WA state and replace the broken automatic in my Bavaria with a rebuilt Getrag 265 5-speed gearbox, using a mix of mostly new factory parts and an occasional used item as needed.  My friend Brant would then fly up later in the week and buy Jason's 1969 2500.  We would then leave on Saturday or Sunday and caravan together to San Francisco (and, in his case, Santa Cruz).  The 2500 runs well but its cooling system was weak and the car had some wiring problems that we wanted to address before the drive home.

The transmission swap took a lot longer than I thought: removing the automatic took up almost an entire day, the horrible thing was really stuck in there and we used all maner of creative hacking to finally free it from the car.  I then installed the flywheel and found that the clutch pressure plate doesn't fit.  I had accidentally been sent a flywheel for an M20 motor, which has a 1/4" smaller diameter for the pressure plate.  Having figured that out, I bought a proper M30 flywheel from Jason and we continued with the install, but this put us into late Friday night for the driveshaft installation.  At this point we realized that the guibo (drivesahft-to-gearbox coupling) that Jason has for me was already installed on Brant's car two months ago when I was up there -- we both had forgotten about that.  It's not really possible to get one of those on a Friday night or a Saturday, but we found a BMW dealer that at least had the E28 5-series version of the part in stock and for sale on Saturday morning.  The part, however, didn't match the drawing in the parts book and therefore was a bit too short for the drive shaft that I had.  We hacked around for a while and Jason finally came up with a very clever way to adapt it.  Finally, with the driveshaft installed and with Seth and Eric's help, we buttoned up the car and were ready to test-drive it.  Seth and Eric also addressed the cooling problems on Brant's car by adjusting the belt tension and upgrading its magnetic fan clutch and five-blade fan to the more modern viscous coupling design with an E12 fan.

It was late on Saturday night, the day before the long trip home, that I finally put the car in reverse, pulled it out of the shop, and really drove it for the first time with the new gearbox.  Everything seemed to work great, so I got in the back and gave Jason and Brant a turn at the wheel.  We heard a weird noise followed by a few scrapes and the car started stumbling and then promptly overheated.  We limped back to the shop and popped the hood to find that a metal support piece that ran vertically up the radiator in the very front had somehow detatched and caught up in the fan.  The radiator was leaking due to a gash from the piece of metal, the fan blades were broken, and one of the plug wires was broken off at the distributor cap.

We worked late into the night to replace the damaged radiator with a decent spare from another Bavaria for the trip home.  We also installed one of Jason's spare fans and replaced the damaged plug wire set.  The car was finally buttoned back up with the cooling system bled at quite a bit past midnight and test-drove rather well.

Brant and I started off on Sunday morning for the long trip back home.  We fueled up, merged onto highway 5 South toward Portland, and kept an eye on our respective coolant temperature instruments.  I heard a stange noise somewhere near Vancouver, WA and then Brant swerved to avoid my radiator fan and fan clutch assembly, which had been thrown from the car.  We pulled off the highway into a gas station parking lot and I popped the hood to inspect the damage.  The fan clutch was indeed missing but, this time, there was no damage to the radiator or wiring.

Jason suggested an electric puller fan strapped to the radiator to cool the car for the trip down and looked up a nearby Schuck's auto parts store to visit.  Brant and I walked in the moment they opened and a helpful employee found us a suitable fan, helped us test-fit it by looking at Brant's car, and made sure that I remembered to at least buy a toggle switch to wire it.  Brant and I removed the remaining fan clutch mounting hardware to maximize clearance and then installed the electric fan which I wired straight to the battery via the toggle switch.  It worked amazingly well: the car ran nice and cool at city and highway speeds, we were back on the road.

We proceeded South after a breakfast and coffee stop in Portland (we randomly chose Blitz's in the Pearl District, I highly recommended it).  The weather warmed up and Brant's car started overheating but we carefully pressed on.  Both engines started running hotter as we got in to Medford so we decided to stop and wait until dark when the weather would cool down again.  This left us with nothing much to do beside finding the nearest Irish pub and eating dinner and having a few beers.  Shenanigan's in Medford fit the bill nicely, in fact it's a really cool place and I'll definitely be back next time I pass through Medford.

We continued on our way to Califronia after the sun set.  The cars ran without much trouble once the weather cooled down and we cleared the Siskiyou mountain pass and continued through the Shasta area.  Brant's car still ran a bit warm so we took it easy through highways 5 and 505 and finally wound up in San Francisco early on Monday morning.  Brant continued to Santa Cruz later in the morning and made it home fine, I parked my car and took the bus to work in the afternoon.

There's still quite a lot to fix on this car, including an exhaust leak I caused by breaking a stud on the rear downpipe.  I still need to pass the DMV brake and lights inspection to get license plates.  It's running and driving well though and the five-speed manual works great.  This has been a horribly stressful experience overall, especially the journey home which was "suboptimal" to say the least.  I'm really thankful for the help and support of my E3 friends!

Friday, September 18, 2009

Early BMW E3 (2500 and 2800) wiring

I'm helping with some wiring repair on a friend's very early BMW E3, a 1969 2500.


The wiring on these is a bit different than on the later ('71 and on and '73 and on) cars and here's the fuse box layout. The fuses are numbered one through ten, left to right:

Parking light and tail light, left; engine compartment
License plate, luggage compartment; instruments illumination
Parking light and tail light, right
Clock; interior light
Lighter, power antenna
Windshield wiper and washer
Stoplight, horn, back-up light, turn signal, auto choke, warning lights (man. choke, fuel, oil pressure), fuel and water temperature gauge; electrical fuel pump
Back window heating, air conditioner
Heater blower
Power sliding roof, other electrical accessories

5A fuses are amber (yellow), 8A fuses are white, and 16A fuses are red. The fuse 7 circuit has quite a lot of components on it and when that blows you'll lose pretty much the entire instrument cluster.


Note that there are no headlight circuit fuses, this came later with the two-row fuse box. I suggested adding in-line fuses for the headlight circuits. I also recommend adding relays for the lights if your car doesn't have them (one for the low beams and one for the high beams) in order to reduce the current flowing through the headlight switch. This was also done on later cars, although it seems to not have happened until the 1973 model year.

Ignition Switch

There seem to be three ignition switch parts for the USA-market E3. The very early cars like this 2500 have a unique ignition switch style that is not interchangeable with the later styles (that is, they don't fit each others' lock cylinders). The part number for this early switch is 61-31-1-352-236 and the part is no longer available from BMW. The part number for the slightly later style (used until 04/1971 production, likely '72 model year) is 61-32-1-350-532 and the part is available. The later switches have slightly different wiring tails, including an additional key position, but they can be spliced into an older-style harness with the additional key position left off.

Replacing the early ignition switch

It's possible to replace the very early version of the ignition switch with one of the later switches, however that involves also replacing the lock assembly and changing some wiring.  The early ignition switch is connected as follows:
  • 12+ from the battery (red) is common to the switch.
  • small gray wire with a plug connector powers the turn signal switch.  This is not a specific switch position but is used for the hazard flasher and side market circuits, along with the turn signal itself.
  • heavy green wire connects to fuse 7 on the fuse box.  This powers the accessories and provides the "run" or "on" position.
  • black wire powers the starter solenoid, the "start" position.
There is no "accessory" position, but that came on the later cars.

Replacing the turn signal stalk

The early turn signal stalk is functionally identical to the later pre-74 stalk but wiring connector is different.  You should try to find the very early type what will plug right in or splice the later type into the early harness.  The very early cars use a rectangular plug with rectangular female connectors inside, the later cars use a square plug with round male pins inside.

The turn signal moved to the left side on the 1974 model year and is that one is a quite different design.

Friday, September 11, 2009

Transmission replacement: a plan of attack

I bought a lovely 1973 BMW Bavaria from the pick-n-pull junkyard a few months back.  The car unfortunately had a barely-working Borg Warner automatic transmission but otherwise is in great shape and I love the color.  I bought the Bavaria with the intention of replacing the automatic with a manual gearbox as soon as possible and my friend Jason in WA state happened to have a spare.  He also happened to be hosting a BMW Bavaria meet-up, WestFest 2009 at his house, so it made sense to pack some bags and head up there on a little road trip.

As bad as the transmission was, I thought I'd make it, especially after giving it a quick servicing and fluid change.  The oil pan was filled with metal shavings and the filter looked disgusting.  The oil that drained out didn't look like ATF.  Still, I changed the parts out, cleaned it up, and put it back together with new ATF.  It worked pretty well for a while, though reverse was a bit spotty up slight hills.  We made it to Jason's just fine and even took it on a group drive up the back of Mt. St. Helen.  Finally, on the way back to Jason's, we headed up a very steep hill and, half a mile from his house, the transmission stopped putting power to the driveshaft.  Oops.

On a positive note, the car is now at Jason's house and we have that spare Getrag 5-speed manual transmission, a lift, and lots of tools and fluids ready to go.  I'm headed up there in a week to swap in the manual gearbox and then drive the car home to San Francisco.  Here's an approximate check list of what's needed to convert an automatic Bavaria to a 5-speed:

  • Getrag 265 5-speed manual gearbox and bel housing.  This typically comes out of a 1980 or 1981 528i but there are other options.  However most of the associated parts (shifter, crossmember, etc) will need to be from an E12 528i, even if your transmission is from another model.
  • The transmission crossmember and mount.  This is used to hold the transmission in the car and it has to be out of a 1981 528i 5-speed.  It's not an expensive part new, so if you can't find a used one, order a new one along with a new mount.
  • The shifter.  Namely you need the shift tower (the big black metal piece), two new shift tower bushings (they're little blocks that hold the tower to the gearbox), the shifter, and the shifter linkage rod and associated clips and bushings, and an insulation pad.  You also need the shit tower rear mount, which is called a "Christmas tree" due to its shape.  It needs two metal brackets and you'll drill a hole in the tunnel for one of them to mount.  These diagrams make it clear.  Make sure you really have all this stuff, the shifter doesn't really work without it.
  • A clutch kit (or the entire set of clutch parts from the donor car).  This is typically the clutch disc, pressure plate, throw-out (release) bearing, and a pilot bearing.  Buy the new-style one-piece (sealed) bearing.  You also need the clutch fork and pivot piece.
  • A clutch slave cylinder: the 1981 528i one will work fine.
  • A clutch master cylinder: the 1981 528i one will work fine.  The mounting point for it already exists, it's where the automatic harness runs through the firewall.
  • A manual transmission car's brake fluid reservoir (it's the same as the automatic one except that there's a third line for the clutch, they're available brand new for about $20) along with some hydraulic lines.  I recommend calling Jim or Spence at Mesa Performance for the lines as they can send you the correct length of hard and flexible line to use.
  • A flywheel from a manual-transmission M30 engine.  You want the earlier (pre-E34 5-series) single-mass type.
  • A set of bel housing bolts for the 5-speed as described in the parts book.  The automatic bel housing has different bolts so you need to buy the right ones unless you have the ones from your donor car.
  • A set of pedals from a manual-transmission Bavaria: the brake pedal, clutch pedal, and the bushings and springs inside them.  These may be hard to find!  You also want the "fit bolt" and bushings shown here, they're used to connect the clutch master cylinder to the clutch pedal.  In addition, get the clutch pedal return spring if you can.
  • A flex disc (or 'guibo') of the automatic style rather than the kind found on the manual cars.  You'll then be able to reuse the driveshaft bolts from your car, and this kind of link is more durable.  The part number is 26 11 1 209 168 or 26 11 7 511 454. 
  • You should also buy a rear main seal and change that out while you're in there, unless you're sure yours is fine.
  • I recommend buying a new reverse light switch for the transmission just in case the one already in it is bad, it's a very inexpensive part.  You'll need the reverse light switch harness from a manual car, or you can make your own.
  • The manual transmission style center console shifter part for the Bavaria.
  • A manual transmission Bavaria or E12 (530i or 528i) radiator would be nice, but not required.
That should about cover it, I hope.  I sort of cheated because my friend Crow and I recently did the same conversion on his 1973 Bavaria so I got to experience it first-hand and refresh my memory on some details.  Craig Dinger has a very good auto-to-manual writeup with pictures and notes about the wiring changes required for 1974 and later cars.  I recommend having that handy.  The SSR site also has step-by-step instructions for the conversion to a 4-speed along with wiring instructions for 1973 and earlier cars.

On a side note: the automatic transmission is a bit longer than the Getrag 4-speed that should have come with the car.  The Getrag 5-speed, however, is about the same length as the automatic.  This means that the automatic car's drive shaft and speedometer cable line up with the 5-speed but not the 4-speed (the speedometer cable is too long and the drive shaft is too short).   I recommend replacing your automatic with the 5-speed unless you've found a 4-speed E3 parts car with everything you need.

draft-802.11s mesh status: 2.6.31 and 2.6.32

Here's a quick Linux draft-802.11s mesh status update:


The 2.6.31 kernel has been released and it unfortunately ships with mesh temporarily disabled. To enable it, edit net/mac80211/Kconfig and remove the depends on BROKEN line under the config MAC80211_MESH section, then configure your kernel.  The problem that lead to mesh being marked broken has been resolved by this patch, which should be in 2.6.32.


A number of issues have been addressed for 2.6.32, including roll-ups to the current 802.11s draft.  For example, we now use the 3-address format for broadcast frames (patch) to work around a problem with some WDS-capable access points already on the market.  The mesh Information Elements have been brought up to date as well (patch), this will help with interoperability with FreeBSD's draft-802.11s stack but of course breaks compatibility with Linux-based mesh nodes that do not have the Information Element patch.

The mesh stack previously relied on the (now deprecated) "PID" algorithm and, when "minstrel" replaced "PID", things broke.  The mesh air-time link metric has been restored by decoupling the failure average statistic from the Rate Control algorithm and fixing early detection of broken links for the "minstrel".  The latter will need to be addressed for drivers that implement their own RC algorithm.


At this time, I recommend testing Mesh Point mode with the b43 and ath5k drivers, however a complete driver status list can be found on the o11s wiki.  It's also possible to use ath9k and rt2x00 but they won't beacon right away.  The workaround is to issue a scan, after which you'll see mesh beacons (bugs 14187 and 13752 respectively).

The Future

Additional draft roll-up work is needed, along with finishing the Mesh Point Portal (MPP) support.  There are also a few minor driver bugs to address.