Question 1: BMW Longevity / Ownership Issues?

[lemming]

Originally Posted by John V

Mike Miller is all-knowing God.

ah.

i thought you were singling out the m3. he was applying that to the entire generation of car.

if you were to use him as the barometer, the upside is that he thinks that the advent of the E46 was a return to normal BMW engineering "quality". that would appear to be offset by the continual window regulator/coolant system bugs that still plague the E46s as carryover.

[John V]

Originally Posted by lemming

i thought you were singling out the m3. he was applying that to the entire generation of car.

He seems to be a pretty knowledgeable guy, but he's a bit locked in the past.

The E46 platform appears to have solved the problems encountered with the E36 platform but in reality the cars are just newer - most of the problems are still there, they just haven't surfaced in most cases yet.

[lemming]

Originally Posted by John V

He seems to be a pretty knowledgeable guy, but he's a bit locked in the past.

The E46 platform appears to have solved the problems encountered with the E36 platform but in reality the cars are just newer - most of the problems are still there, they just haven't surfaced in most cases yet.

in that regard, i really don't know what's worse: the RMS problem that Porsche recognizes and handles (quite well) under warranty or the out of warranty cooling system issues that all BMWs seem to have?

[John V]

Originally Posted by lemming

in that regard, i really don't know what's worse: the RMS problem that Porsche recognizes and handles (quite well) under warranty or the out of warranty cooling system issues that all BMWs seem to have?

The range of items that fall under the "BMW cooling system problems" heading really needs to be looked at here, just as a reality check. I'll admit that I was pissed off when my radiator neck blew two days before the new owner came to pick up the M3. For that to happen to a car that has seen regular coolant changes all its life is, IMO, inexcusible, even if the car is ten years old and has 70k on it. Other manufacturers have managed to make radiators with plastic endtanks that don't degrade and fail - I have no idea why BMW can't figure it out. Regardless, an E36 rad is under $150. Not a big deal to spend that every 50k miles (that's four years of driving for me) and have a good safety margin.

A couple guys I know personally have had their overflow tanks explode at the track. Apparently the same thing affects the MINI, since there is at least one company offering an all-metal catch can to replace the factory overflow tank. Appears to be the same problem as the rad endtanks - cheap plastic that degrades with exposure to coolant and temperature cycling. It's a cheap part, under $70.

The -'95 plastic impeller water pump fiasco was an E36 mistake that shouldn't have happened but the bigger mistake was the influx of cheap aftermarket metal-impeller pumps that were worse than the original plastic part. BMW redesigned the part for the late '96 and on cars and they last a long time. But like any water pump on any car, they really should be replaced every 60k-70k. Water pumps are wear items. The factory part is cheap. Under $100 including a t-stat, which should be replaced at the same time, but they don't fail too often in BMWs.

I really think this all has been blown out of proportion a bit, but then again I'm someone who likes wrenching on cars and fixing stuff like this is cake compared to replacing an RMS which will probably start leaking again anyway . (FWIW, 28k on my '00 and it doesn't leak - never has)

[lupinsea]

Hm, interesting.

So how easy/difficult is it to access the water pump, t-stat, and radiator to change those out? It sounds like the parts themselves aren't that bad and that maybe a "regular schedule" of every XXXXX miles to do everything may be a good habit to get into. I mean, if you're pulling the radiator I imagine it would be easyer (since it's then out of your way) to also get at the water pump? I have no idea of the layout of the BMW 3 series engine compartment but I would suspect the water pump is up front?

Ha! I remember replacing the water pump on my old '77 Corvette (Yeah, I've learned a bunch since then). Cost me a wapping $20 for a new part and took about and hour to do in the drive way. Didn't need to get under the car at all apart from draining the radiator petcock valve.

[John V]

Originally Posted by lupinsea

Hm, interesting.

So how easy/difficult is it to access the water pump, t-stat, and radiator to change those out? It sounds like the parts themselves aren't that bad and that maybe a "regular schedule" of every XXXXX miles to do everything may be a good habit to get into. I mean, if you're pulling the radiator I imagine it would be easyer (since it's then out of your way) to also get at the water pump? I have no idea of the layout of the BMW 3 series engine compartment but I would suspect the water pump is up front?

Ha! I remember replacing the water pump on my old '77 Corvette (Yeah, I've learned a bunch since then). Cost me a wapping $20 for a new part and took about and hour to do in the drive way. Didn't need to get under the car at all apart from draining the radiator petcock valve.

The radiator is a 20 minute removal job and does make getting at the t-stat / pump slightly easier, but it's by no means a requirement.

It's been a while, but IIRC the thermo housing comes off next (a few nuts / bolts) and then the water pump. I think I took 1hour to remove and reinstall the thermo housing / WP, but only because I was doing a "hey neato" on each of the parts.

Honestly the hardest / most frustrating part is burping the cooling system. BMW didn't see fit to put a jiggle valve on the E36 thermostats (I ASSume the E46 is the same). I drilled a 1/8" hole at the top of mine to speed it up, and it did help a bunch.

It's all very easy stuff that a person comfortable around cars and tools could accomplish in a few hours.

[ff]

Originally Posted by John V

Honestly the hardest / most frustrating part is burping the cooling system. BMW didn't see fit to put a jiggle valve on the E36 thermostats (I ASSume the E46 is the same).

No bleed valve?? WTF

[FC]

Originally Posted by ff

No bleed valve?? WTF

Yeah, that is pretty F'd up. It's like 987's/997's with no oil dipsticks.

[robg]

Originally Posted by lupinsea

Robg, (or anyone else) when you talk about the "later E46 cooling system" being more reliable what years are you talking about? '01 and up? '03 and up?

I guess late 2001+ cars since they supposedly have a better thermostat (earlier ones broke), and a better waterpump design (although I think that started w/ late e36). Regardless, I woudlnt' put much faith in any modern BMW cooling system, so its a moot point as to which is "better". Just replace everything at around 70k and you should be fine. If you DIY, it shouldn't be too expensive.

[John V]

Originally Posted by ff

No bleed valve?? WTF

Not unless you drill your own, no.

It's especially bad if one drains the block (as one should) during a coolant change. There is only one effective fill point and that is the radiator overflow tank. So without the jiggle valve the only way to really bleed the thing is several heat up / cool down cycles.