sotek

Got the low coolant message a few times over the last few days.... and it's now showing the float fairly low... i looked around and saw some green crusty stuff on the waterpump to thermostat ... looks like the seal between the two isn't quite sealed.. there was also a bit of a wet mark on the splash guard under the engine. So i guess I'm leaking coolant out through this seal (or lack there of). My query now is whether it's a waterpump issue, thermostat issue or just the gasket giving up in this horribly hot whether (48 degrees celsius with humidex yesterday.. probably 40+ in the sun where my car was parked.

Could anyone offer me some pointers? I'm car stupid but intuitive enough to figure some stuff out... my goal is to diagnose, buy the parts and have the young guys (not that I'm not still wet behind the ears) at the shop down the street fix.

Any help would be greatly appreciated!

sotek

Also - is there any danger of topping it up with tap water to get it over to the shop (5km)? Since it'll likely need to be refilled after the work, I'll just have them flush it - is using tap water still a 'no no'

luigi524td

Pick up a gallon of distilled water - keep it in your trunk and you can use that for lots of other emergency top-offs. A few ounces of tap water won't hurt if your mechanic it going to do a flush and refill after repair BUT be sure they use pre-mix or distilled water for the 50-50 mix after repair.

sotek

Cool - It seems to be a very slow leak - I'll put some good ol' tap water in there. Should it be safe to hit up the grocery store (18km round trip) or should I just wait it out until Monday and fill it to drive it to the shop - I imagine the seal will hold up but who knows.. my big concern is with the water in the system.. would a few cups over the course of the weekend cause any damage to the poor old girl?.

Just spoke with the indy shop - they'll have the O-ring Monday morning. I requested they flush and refill with BMW Coolant.
He mentioned that DexCool (Red GM stuff) would be fine since it was designed for aluminum components but I insisted (due to what I've gathered in the forums.. and only for a few bucks more a gallon it can't hurt to use BMW).. anyhow they're going to replace the o-ring (hour to 1.5 labour) and do the rad/coolant flush $69 + 20 for the 'fancy coolant' all toll less than $200 for the fix. Not too bad considering the mess and my lack of knowledge .. sure I could change the gasket but bleed the system .. do I cut it? LOL (j/k'ing) :-)

porando

NOOOOOOOOOO.... Dont drive this car if you want to keep it for a while...Don't add water and be be happy that you have small leak...
RUNNNNNNNNNN to the shop in a real hurry and replace your water pump and thermostat.... unless you like to be stranded on the road with lots of smoke coming from under your hood?
BMWs are notorious for blowing pumps at around 70- 90k miles so all smart owners change them at around 60k....

sotek

Not to sound like a smart ass but why would I replace the water pump and thermostat for a gasket leak???
Could it be a sign of other things????

porando

just because you don't want to do this job again for a while and you want to be sure that nothing else will fail.
- Pumps fail - bearings leak, rotor blades brake etc...replacing just gasket is cheaper of course but I would replace the whole thing...
- thermostats go bad as well.thermostat replacement will be be much cheaper when you do at the same time and part cost is small as compare to other (fluid/labor)

sotek

True that - I hear what you're saying. There's a Graf and a OES/OEM BMW Water pump - BMW is $277 - Graf brand is $177 - Graf has a metal impellar, BMW has a composite impellar - my understanding is that metal impellars are better as the composite can shatter and destroy the cooling system in the event of failure. Any recommendation on the pump, I don't mind spending the extra money, but I'd really rather have a metal impellar given my research.

John@Motorcepts

if thermostat goes, ui'll have a check engine light. Ur leaking coolant at the thermostat. Around 50K miles, thermostat goes on V8 E60s. Might as well replace that and the water pump. Might as well change the timing belt if you're approaching 100K miles.

porando

What kind of shop you are using? I wouldn't trust anybody who is not a BMW mechanic - too many specifics issues and procedures with BMWs and there are many good BMW guys...
I have never heard in any BMW places where they would recommend replacing only O-ring.... gas station shops maybe....BMW pumps fail and bearing leaks or broken blades are common...unfortunately.. so replacing just o-ring is leaving unexploded bomb there...you maybe lucky but I wan to be safe.
I try to save money in places where it is not safety concern or I wont be stranded on the road in case of trouble....So no shortcuts on brakes, lubricants and cooling system components
I use only BMW coolant because I know it was tested. (Actually I buy MB as it is the same and is cheaper)
I wouldn't recommend flushing coolant yourself - not hard but very messy job....