I recently bought an 89 635 with 139K, had it professionally checked out, and got a fairly decent price but four months later at 143K I am having issues: I have already replaced the master and slave on the clutch, now I need brakes and a host of other things including a new hydro-booster and possibly a radiator...as a poor grad student I am beginning to wonder if I got taken and had better cut my losses. I love the car in theory but not sure the reality is living up to the packaging...any thoughts on whether its worth sinking more funds into or try to get out? Also, any thoughts on locating a front air dam (not a knock-off but the real deal?)

Maintaining these old BMWs, is both expensive and hard to do, that is why there are over a hundred maintenance forums online for each model.

Most of the items you mention would be considered normal maintenance issues.

You may want to learn to fix it yourself.

Asking here is the best start, then decide if you want to do it or out source it to a independant garage.

Many persons posting and lurking here are in the same situation.

All would rather be driving a shark than wrenching one.

http://members.roadfly.com/kcroncarter/Shark.GIF

Later,

i would venture to say that most owners dont have the 6 as their primary transport(as in,no backup),unless of course,they have the funds to keep it rolling whenever a problem arises.can you buy a beater and park your 6,that way you'd have it when you're able to address issues.i'd keep it if you can go that avenue.
as KC said,it's not cheap to own(or drive)the ultimate driving machine.i do all my own work and have to save for replacement parts.for me,that's just life.i have a reliable daily driver and the 6 sits there,patiently waiting,to be fed good 'ol american dollars.

I'd agree with the other guys... I've owned my shark since late spring, and since that time I've installed new wheels and tires (cheaper than replacing the TRXs!), a new Optima battery, the downpipe and cat, the driveshaft and the the lower control arms. The new tie rod assemblies are waiting in the wings. Total cost at this point has been a tad over $1400 above and beyond the initial purchase price. Next on the list are the clunky front strut bearings and probably new shocks all the way around. And this is a car in excellent overall condition with an immaculately detailed service history! My little girl arrives in February, so planning for that is going to dictate how much and how long it takes to replace the other stuff.

The car sat in the garage for almost two months awaiting assessment, saving-up, and purchase of the driveshaft and exhaust components, and I just got it back on the road last week. To that end, I have a venerable Amurrican pickup to tool around in when the Bimmer's down or the weather's bad. Having owned several high-maintenance cars in the past (16-valve VW Scirocco, anyone?), it just makes sense to keep some kind of semi reliable beater around as a backup.

Whew. All that having been said, the ol' girl runs like a top, and I had a huge grin on my face passing traffic on the high side of 90 mph yesterday after work. Gotta keep the cobwebs blown out and all that stuff! There's nothin' like a shark...

I recently bought an 89 635 with 139K, had it professionally checked out, and got a fairly decent price but four months later at 143K I am having issues: I have already replaced the master and slave on the clutch, now I need brakes and a host of other things including a new hydro-booster and possibly a radiator...as a poor grad student I am beginning to wonder if I got taken and had better cut my losses. I love the car in theory but not sure the reality is living up to the packaging...any thoughts on whether its worth sinking more funds into or try to get out? Also, any thoughts on locating a front air dam (not a knock-off but the real deal?)

Everything on the 6 is relatively simple, except for the wiring. It is a very basic machine, really.
I would suggest learning to work on it yourself. That will ensure MANY MANY years of ownership. If you cant work on it yourself, you are digging yourself a hole as a student. Look around for good used parts. I have a radiator for your car that has about 10 miles of use on it, etc. I paid a lot for it, but I would let it go for $100.

The best thing is to not be afraid to ask questions. People love to help out, and no one will ridicule anyone in the 6 series forum.

Aye - I say keep it -

These cars are slowly going up in resale and collector value - Baby boomers are retiring and getting cars to play with - these being one of them..

Brakes/rotors aren't that hard to do yourself - just buy a pressure bleeder and you'r basically home free.

Same thing with a radiator - remove the hoses, fan assembly (the one that comes off of the water pump with the fan clutch), fan shroud, remove the mounting bolts (there are only 2 I believe; 4 at most) and it lifts right out -

Stick new (or new to you radiator) back down in slot; re-attach everything in reverse order - refill with good old - phosphate free antifreeze and distilled water; bleed it with engine running - tha'ts that little bolt on top of the T'stat housing - tighten it - run it a bit around the block - carefully watching temp indicator -

repeat bleeding procedure until you've got a nice stable temp and you're home free..... :D

I agree with Funkmasta. These cars are relatively simple to troubleshoot and repair, but the key to making owning one of these cars affordable is to do the work yourself, if you don't, then I say sell it. If you are willing to do the work yourself, get yourself a Bentley manual and ask questions here...we'll help you.

Although I do currently have 3 cars and a truck (used to have 4 cars but I just sold a 1990 Audi CQ), I will soon make my 6 my daily driver. I currently have a drive shaft problem, but I caused that my self. As soon as I fix that, I will be driving it daily... and I drive about 100 miles per day. I have that much confidence in this 155k mile car. I also have a couple of freinds that drive e28 535s as their daily drivers.

I will be acutally going against the norm practical logic by selling my 2003 honda accord ex (with a stick) daily driver so that I can drive my 6 daily.

Hey man, and you live in LA, where the weather is pretty much perfect year round, you don't need a winter beater or anything like that. Try to keep it.