I have been looking for a nice classic 635. I think the early 635's and 3.0SCi are the prettiest cars BMW has ever made. I found mine on e-bay (my first e-bay car purchase). I fell in love with it and probable paid too much for it but I do not think about that too much. I will post a photo of it when the weather stops raining and snowing. Now that I have been driving it a few months I have a few things I want to fix/change. I do not think this was a daily driver an I do not think this car was made to just sit in the garage. I want to drive it and take it to some club track days. The first few problems I want to fix are: 1 - Fuel leak when I fill it up: When I fill it up and park it for awhile I get a puddle of fuel under the center of the trunk. After I drive it about 1/4 tank the leak stops. I have replaced the fuel level sensor (it was broken) and the o-ring and it did not fix the problem. Are there any other penetrations in the fuel tank to check? 2 - Hood does not latch: The shaft the latch handle is mounted to looks bent and the handle slides off. Can it be straighten or replaced? 3 - Radiator nipple broken (short) on top return hose: Can the plastic radiator ends be replaced? If not, where is a good place to get a radiator? 4 - Intermittent instruments: How do you remove the instrument cluster? I want to clean up and tighten all the connections to the cluster and reflow the solder on the circuit board. I had to do this on one if my 318's to fix these types of problems. 5 - Change service interval computer batteries: Does this car have batteries on the SI board, like the 318i? If so, where can I get replacements? 6 - On-board Computer set-up: This too is intermittent so I want to clean up the connections here too. How does this computer work? How do you set it up? The owners manual I have is from a post 83 and the computer is different so the manual is no use. Does anyone have a manual for it or know where I can get one? Any help any of you can offer would be much appreciated. I look forward to meeting some of you at a club event somewhere. Thanks.
On the fuel tank leak, I haven't done this yet on my E24, but I'll assume it's much the same problem as with E21's. You really need to replace all the rubber hose connections at the tank. Start with the supply/return lines. If it's like the E21's you'll need to drop the tank a little. Not completely, just an inch or two for room to work. Last thing I'd change is the fill hose, but try renewing the supply/return lines first.
jwarthog.com In addition to the advice given, be sure to check fuel tank itself, especially the filler neck and surround,particularly if the ancillary pipe checks don't give you an instant answer. It's not unknown for E24s require a tank replacement at 20 years of age...
I, too, have fuel tank issues. It used to weep gasoline on fill-ups (probably still does but I'm sure the summer heat is evaporating it now). I would notice the tank to be wet on the side. It mainly leaks fumes into the passenger cabin, worse in the summertime than the winter, but still noticeable. I'm going to look into the filler cap, and I have been told that there is a seal where the filler neck meets the tank that is prone to rotting out. As for the intstrument cluster - I have an 85 euro 635csi, and I'd assume that the procedure is the same: 1 - Assuming that it still has it, you will need to remove the driver's kick panel. 2 - You will need to drop the steering column in order to have cleareance to get the cluster out. There are two bolts on either side of the base of the column holding it in place (I wanna say 15mm, but I don't honestly remember). They are positioned where the column meets the underside of the dash...waaay back in there. Lining them back up once your done can be a pain, but doing it properly will save you from stripping them. Ask me how I know!!! 3 - The cluster itself is held in place by two screws on the underside of the top lip of the dash, and some hidden screws, IIRC. 4 - This is all from memory, but I'm pretty certain that you have to take out these hidden screws. They are located behind the check light panel on the left side and behind that little strip of plastic panel just to the immediate right of the cluster. The strip panel comes off with a flat head, and you will need to remove the cover for the check light display also with a flat head. Be very gentle on removing the check-light cover. I almost broke mine the first time I tried taking it out!!! 5 - You will find some screws behind the check-panel cover that you just took off. Remove these screws and the panel will lift out. 6 - There are some screws behind this panel that are holding down the left side of the instrument cluster. Don't remember about the left side, but I'd HIGHLY recommend a magnetic screw driver. It may not be evident here, but you will see why in the next step. 7 - There are yet more screws behind that plastic strip-panel that was mentioned in Step 4. Taking these out will free the right side of the instrument cluster. Remember that magnetic screw driver? I'd keep my hands steady here too, because these next three screws are buried in there. There is nothing below them to catch them if they fall, either - again, ask me how I know!!! This thread over at BimmerForums is a build thread on a US spec 83 633csi, but the procedures should be very similar. The link below is the starting point where the SI board batteries were changed out. I believe you'll find some OBC related issues covered there, too. http://forums.bimmerforums.com/forum/showthread.php?t=531693&page=12 Good luck! Alex BTW - Newbie to posting here, obviously. How do I change my display name to read something other than my membership number? Thanks!
