Preventative Vs. Overspend. E46 Content.

So my new (to me) E46 just hit 90k miles on it, about the time to start taking a really good look at the coolant system and giving it a refresh. My question is, everyone has their take on what to refresh. Some say just do the pump and tank, others say do that plus the T stat, plus the sensors, etc. I'm not cheap by any means, but I also don't want to just throw parts at a car when the ones I am removing would be totally okay. So, the kink below is a "refresh kit" offered by ECS Tuning. This is their more involved kit, the lesser one is mainly the pump, hoses, etc. while this includes sensors, a new t-stat, etc.

Cooling Refresh II Kit

Vs. This lesser kit....

Cooling Refresh I Kit

Also, now that autumn is settling in and the mornings are cooler, I have noticed a bit of squeal on start up. From what I have been reading, this can probably be attributed to the pulleys or tensioners. ECS has this kit available, but want to make sure that I am not missing anything, or barking up the wrong tree (or, squeaking, I guess)

Drive Belt Kit

The drive belt kit and the stage II cooling system kit have some overlap.

I think the stage I kit and the pulley kit would do well for you.
The pumps and t-stats fail almost as often as the reservoir tanks. The hoses don't fail too often, but more than once the o-ring doesn't seal well on the radiator and tank after they are replaced. So I end up doing the hose after all.

The cold start noise is most likely your idler, but I ALWAYS replace all the tensioners while I am in there.

Those look like some pretty good prices BTW

I managed two service shops that did a lot of e46 service.

The trouble you run into is that once disconnected you may have trouble getting the system to seal back up. AFAIK the orings for the hoses are still NA. The fan switch (goes in the lower hose) seal can be ordered but they do go bad.

If its auto and you are going to do the resevoir, make sure you have a source for the A/T cooler tstat. They break frequently and will hold up the job.

The tensioners/idlers do fail. Sometimes in spectactular fashion. If you pull the belts off and spin them by hand and hear the "ball bearing sound" they are starting to go. They should be silent.

Good luck!

Personally, I'd replace everything plus the radiator and the fan clutch (as I did on my E39). You can get o-ringed brass bleed screws to replace the trouble-prone plastic ones as well. Go in once and call it done.

All of the plastic cooling system parts are dated, if they're original do them.

The hoses, thermostat and pump all have little date "clocks" which have the year at the center with an arrow pointing to the date of production. The expansion tank and radiator have date stickers.

Check the fan clutch for fluid leakage, if the magic juice is escaping it's time to replace.

Agreed with 02Pilot. Drop a grand on it and get an aluminum radiator, aluminum tanks, electric fan, plus all of the assorted belts hoses and pump.

In reply to DILYSI Dave:

Triple agree, just had the plastic tank esplode on my moms e46 at 105k, lucky she noticed the low coolant light and stopped driving.

I'm 90% sure I already have an electric fan, as my car is a manual not an automatic

But yes, the tank is on the list of cooling system upgrades. I need to look more closely later today when I am home and see if it has ever been changed out. I don't have any records other than what shows on car fax (which, actually, is pretty thoruough and all through Hudson BMW upstate). The last cooling related anything was a coolant flush about 10k miles ago when they changed and flushed all of the other fluids in the car.

I did our 330xi auto cooling system at 95K, the car has run without a hiccup since this was done in 2011.

DILYSI Dave wrote: Agreed with 02Pilot. Drop a grand on it and get an aluminum radiator, aluminum tanks, electric fan, plus all of the assorted belts hoses and pump.

They don't make aluminum tanks or radiators for the non-M E46 yet. Plastic is your only choice.

I did the pump, t-stat and coolant tank on my E46 at 105K. Hoses seemed fine, as did the radiator. YMMV. I sold it 5K later but I'm sure it'll be fine.

SlickDizzy wrote:

DILYSI Dave wrote: Agreed with 02Pilot. Drop a grand on it and get an aluminum radiator, aluminum tanks, electric fan, plus all of the assorted belts hoses and pump.

They don't make aluminum tanks or radiators for the non-M E46 yet. Plastic is your only choice. I did the pump, t-stat and coolant tank on my E46 at 105K. Hoses seemed fine, as did the radiator. YMMV. I sold it 5K later but I'm sure it'll be fine.

Well... they do... But it's going to cost you.

http://www.zionsvilleautosport.com/store/screen/ctgy/store_code/6134/category_code/CCSE46.htm

I don't think I need to shell out for an all-aluminum radiator. She's not an M and I don't intend to track it much. It's mostly serving as a fun commuter for my long hauls out to PA 1-2 days a week.

But I figure, if I do the tank, the pump may as well be done too. I just wasn't sure about the Tstat and the various sensors, etc.

This thread is relevant to my interests.

<~~ 96,000-mile E46 owner

Yup, I just hit 90k. That magic 85-110k mark. I'm especially considering since I have the cold-start tensioner/pulley squeal so I need to get in there anyway.

You are going to HAVE to do the pump to avoid the crappy plastic OE impeller exploding and taking your entire cooling system with it. I installed the EMP Stewart pump in mine, which was probably overkill, but at least get a decent pump with a metal impeller to replace it. Don't reuse the crappy plastic pulleys either, if they even survive the first removal. T-stat is also a must do, and it's only an extra three bolts anyway. 01-up E46s have aluminum block engines that do NOT take kindly to overheating, so don't skimp on cooling stuff.

The plastic impeller problem stopped somewhere mid 1990's. Bearings and seals are the typically end of a water pump. I install around 100 Saleri plastic impeller pumps per year and have never seen an impeller failure. The only water pump pulley failures I see are due to severe water pump bearing failure or incorrect removal.

@slickdizzy - are you referring to the waterpump plastic pulleys? That's the only one that I have seen as being available in aluminum, the others seem to come up as plastic only.

Also ECS tuning has 3 pumps with metal - Gaba, GRAF and HEPU. All are in the 50-70 range. Recommenedations? (BMW, with it's plastic composite impeller, is over $100).

ansonivan wrote: The plastic impeller problem stopped somewhere mid 1990's. Bearings and seals are the typically end of a water pump. I install around 100 Saleri plastic impeller pumps per year and have never seen an impeller failure. The only water pump pulley failures I see are due to severe water pump bearing failure or incorrect removal.

Yeah, they went from plastic to 'composite' which still gives me the heebie jeebies. Sounds like they work well enough for you though!

redhookfern wrote: @slickdizzy - are you referring to the waterpump plastic pulleys? That's the only one that I have seen as being available in aluminum, the others seem to come up as plastic only. Also ECS tuning has 3 pumps with metal - Gaba, GRAF and HEPU. All are in the 50-70 range. Recommenedations? (BMW, with it's plastic composite impeller, is over $100).

Yeah, I mean the WP pulley. I put an ECS lightweight pulley on mine when I did the pump. At least replace it with a new plastic one.

Lots of people seem to like Graf parts. OE BMW is always overpriced and always someone else's reboxed part with a BMW logo stamping anyway.

redhookfern wrote: I don't think I need to shell out for an all-aluminum radiator. She's not an M and I don't intend to track it much. It's mostly serving as a fun commuter for my long hauls out to PA 1-2 days a week. But I figure, if I do the tank, the pump may as well be done too. I just wasn't sure about the Tstat and the various sensors, etc.

You may not need to go for the all-aluminum upgrade, but you should replace the radiator. If not, you'll likely see it crack at the filler neck before long.

I thought the E39's were more prone to that issue (esp the 540's) than the E46's

I went with a Graf water pump on my E36, the consensus on bimmerforums (I know, I know) at the time was that it was the best oem-type option for the E36.

E39 540i engine bays are packed pretty tightly and are the most prone to cooling system problems, but the I6 cars will fail, usually a little later in life. The E46s have the same plastic tanks on the radiators and run just as hot. The same plastics in the same heat - you do the math.

I've heard too many instances of replacing some cooling parts only to have others fail soon after to ever consider anything other than full system replacement, but that's just me.

No I totally get what you are saying. I was just curious. I'd like to do most of it myself if I could. I wish I was also closer to folks with the driveway and tools to do it.