Can you diagnose this?

Taco4life

Registered User
Location
Bountiful
This isn't 4x4 related, I have an issue with my commuter, and am wondering what your thoughts are on the issue I am having.

I have a 2000 BMW 323i that just turned over 105k, I took it to my local mechanic two weeks ago to have them change the oil and replace the ball joints. This took a few days for them to complete, in the process they checked all of my fluids and topped them all off. The coolant sensor came on a few days before I dropped it off, and was low. They mentioned that this was one of the low fluids that they replaced. I was grateful for the service that they provided. I picked up the car, the total bill was just under $800. I drove the car home, drove it to church two days later (a total of 30 miles at most round trip) The car then sat for a week, I have been sick and haven't driven much. On Friday I drove it to a class I attend near my church. The coolant sensor came on and the heater wasn't working, so I turned it off. As I pulled into the parking garage the check engine light came on. After the class I had a doctors appointment 10 miles away, the coolant light came on again, then the check engine light. I was 4 blocks away from the doctors office so I decided to just park it there. At the next light my car shut off and took a moment to start again. I drove the few blocks parked it, and it started smoking. I lifted the hood and saw coolant on the block. I let it sit while I went to the doctors appointment. My mechanic was only a few blocks away, I drove it over there after the appointment. The check engine light came on and I watched the engine temperature rise. When I got there we looked under the hood and found the coolant reservoir to have a large crack down the side, also a large crack in one of the pipes leading off of the radiator. My mechanic replaced the reservoir, the broken pipes, and the thermostat. They started it up, it was still overheating and the coolant wasn't circulating properly the top tube was hot while the lower was cool. So they replaced my water pump, now it cools but the engine but the heater doesn't work. They flushed the heater core and now say that the heater works. I am a little irritated now after just having an $800 repair I am now looking at another $900 bill.

Sorry for the long story, I am wondering if you guys can diagnose what you think caused this to occur. Why would the reservoir heat up so much that it would have a 4" crack in it?
 

Taco4life

Registered User
Location
Bountiful

I have been thinking it would be something like this. The mechanic is the last one who filled it with coolant last week. I just received a call from him, explaining to me that the heater core had some white gunk in it, he thought it may be Stop Leak. And now he is suggesting I get a new heater core. What started as an oil change has now turned into my entire cooling system being replaced minus the radiator, and now it looks like my heating system has gone to putts as well. :mad:
 

Darwin

GREASE MONKEY
Location
sandy
bmw has a goofy procedure for bleeding the cooling system. if its not followed perfectly its nearly impossible to get the air out of the system. another method is to use one of those vacuum cooling system fillers. they are a life saver for tough to bleed systems!
hope that helps. on a side note the fan clutches on those go bad quite often.
 

Kiel

Formerly WJ ZUK
Those stupid radiator hoses with the o rings always leak near the radiator nd the enclosed thermostat housing. It sounds sorta coincidental especially if they only topped it off as it sounds
 

Rot Box

Diesel and Dust
Supporting Member
Location
Smithfield Utah
I've seen a few of the plastic/aluminum radiators crack from being over heated. It sounds like the water pump was the root cause of that problem. So that makes sense to me.

Heater cores often harbor contaminants in the cooling system--its surprising how much crap ends up there! If you're sure the air is purged and it still doesn't produce heat from the vents try this: I don't know how easily it can be done on a BMW, but I like to unhook the inlet and outlet hoses and flush the core out with a garden hose. Put one hose (might need to install a longer hose for this) in a bucket and flush all the crud out. Swap the hose from the inlet to the outlet and flush the core back and forth both ways. If you have a decent flow of water you can usually rule out a plugged core. Remember once you are done to push all the city water out with distilled water or antifreeze then button everything back up. If you do flush a lot of crud out it might not be a bad idea to pull out the thermostat and check it. It can trap contaminants as well...

That said from the sounds of everything I'd bet you have an air pocket :D Post back if you figure it out.
 

Taco4life

Registered User
Location
Bountiful
Well after all is said and done, it could have been a number of factors. We found a bunch of stop leak in the heater core and along one of the coolant pipes. I now have heat when I am around 2500+ rpms so if I get it on the freeway the heater works fine, but if I start it up and expect to defrost my window it doesn't work. We did flush out the heater core with a garden hose and remove a fair amount of gunk, however the back half of it is out of reach unless we pull the intake. After researching it a bit, it appears the BMW coolant reservoir tanks are known to crack as early as 60k miles, and some owners replace them as preventive maintenance. It just baffles me that it all happened at the same time.
 

Brian P

Misanthropic Fuel
Location
Taylorsville
Yes, We had a overflow tank go in a few years, Less than 15K miles, But who knows how long it sat on a shelf.
Bummer on the stop leak stuff.
 
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