Engine overheated!

[pmlzl]

I drive a 135i and I jumped in to run some errands and noticed that my heater was blowing cold air, then I got an Engine Temp High alert. I slowed down and several minutes later received an Engine Overheated alert. I made it home and have not checked coolant level. Any thoughts on why my engine is overheating? In need of coolant?

[Lambobimmer]

My guess is bad waterpump or thermostat. How many miles?

[pmlzl]

42,000. I have done some reading and come across people that have had the same thing happen and I was the water pump. Could it just need coolant!?

[631twentyeighteye]

If it never alerted you to low coolant then i doubt it. BMW's are notorious for water pumps going bad early.

[pmlzl]

True, it sounds like a water pump doesn't it?! Thank you for the input!

[1911A145]

Replace the water pump...

[135Pats]

waterpump+thermostat...yet another BMW with one of these going out with very modest mileage, I hope you're still under warranty. It sure seems like once you clear 35K your water pump is on borrowed time, which is insane IMO.

[pmlzl]

I am not under warranty! Fml

[smellthebeans]

Water pump....

[Dackelone]

pmlzl - please post here how long your water pump lasted. I'd for everyone to keep the community updated with how long their pumps are lasting.


how long did your first water pump last?
http://www.1addicts.com/forums/showt...4#post12932454




also check out these kits...

[B]e8x e9x electric water pump $439...
http://www.turnermotorsport.com/p-27...53-engine.aspx

And here is there e8x e9x electric water pump and thermostat kit $571...
http://www.turnermotorsport.com/p-16...-e60-535i.aspx

ALL bmw cooling "kits"...
http://www.turnermotorsport.com/c-10...ter-pumps.aspx


As to when one should replace their waterpump... (taken from Turner's website e8x pumps)...

...How to avoid a water pump failure in the future? Replacing the water pump as part of a regular interval schedule will ensure you always have a functioning pump in place. Since this technology is relatively new for BMW, therefore the lifecycle of the pump isn't yet known, we have been recommending replacement every 80-100k miles. This package of OE/OEM parts covers everything with Original BMW coolant offered to finish off the job. A proper bleeding procedure must be followed with the new electric pump.

Tischer (getbmwparts.com) and Dan at United BMW (unitedbmwonline.com) both offer factory water pump and thermostat kits for similar money. You will need BMW coolant and labor should be a few hours work.

[pmlzl]

Is there a low coolant alert? Or is it the high engine temp alert? I checked the coolant and it looks like it is at the minimum level or below. Not really sure if that stick is supposed to be bobbing and how far it should come up, have to look at it again

[smellthebeans]

One should not have to regularly add coolant. In your case you may want to try topping it off, test drive it and see what happens. If the engine overheats again please, I implore you; Do not attempt to limp back home or to a garage. When safe cut the engine and coast to a safe location. Better safe than sorry and out even more money trying to save a few bucks on a flat bed.

[135Pats]

Originally Posted by smellthebeans

One should not have to regularly add coolant. In your case you may want to try topping it off, test drive it and see what happens. If the engine overheats again please, I implore you; Do not attempt to limp back home or to a garage. When safe cut the engine and coast to a safe location. Better safe than sorry and out even more money trying to save a few bucks on a flat bed.

+1, a limp mode is one thing, but if your engine is saying "too hot!" do not drive it, period. Putz around and see if it comes back on, but if it does shut it down then and there, and call a tow truck. It's a miserable situation, but there's no sense in risking the engine over a water pump. I still cannot believe BMW has managed to produce such a pathetic part a decade plus down the line

[smellthebeans]

who knows....It's a crap shoot. I have seen some N52s & 54s/55s with well over 100K miles on the original water pump. Mind you....I dont recommend trying that at home.

[rking117]

Originally Posted by pmlzl

I drive a 135i and I jumped in to run some errands and noticed that my heater was blowing cold air, then I got an Engine Temp High alert. I slowed down and several minutes later received an Engine Overheated alert. I made it home and have not checked coolant level. Any thoughts on why my engine is overheating? In need of coolant?

most likely it is the water pump. Not likely the thermostat. It could of course be a hole in a hose but you should have noticed steam.

[Dackelone]

Originally Posted by pmlzl

Is there a low coolant alert? Or is it the high engine temp alert? I checked the coolant and it looks like it is at the minimum level or below. Not really sure if that stick is supposed to be bobbing and how far it should come up, have to look at it again

Yes, there IS a low coolant light AND an over heating alert light as well. For the over heating light, first there is a yellow and then a red (!).

The red stick inside the coolant expansion tank should be(atleast!) level with the top of the tank when the engine is cold.

Checking & adding engine coolant DIY
http://www.1addicts.com/forums/showthread.php?t=401672



As for how long the water pump will last... I think it depends on who the supplier was(I am sure bmw has more than a few suppliers) and how good the bearing inside the pump was. Its all a crap shoot.

[dtwyim]

Originally Posted by 135Pats

. It sure seems like once you clear 35K your water pump is on borrowed time, which is insane IMO.

35k!!??

[135Pats]

Originally Posted by dtwyim

35k!!??

Check out Dack's thread on waterpump/thermo failures, though most guys getting failures seem to be getting them in the 60K+ range, i've read/seen enough failures under 40K to say that the part is downright pathetic. BMW did so much right with our car, it's annoying to have to worry about a water pump when i'm not even at 40K miles yet

[Pablito1702]

Originally Posted by 135Pats

+1, a limp mode is one thing, but if your engine is saying "too hot!" do not drive it, period. Putz around and see if it comes back on, but if it does shut it down then and there, and call a tow truck.

+2 at any time an engine hot light comes on in a BMW shut the engine off immediately. I warped the engine head on a 735i because I was overheating and looking for a safe place to pull over. Shut it down!

[m7ammed]

Wouldn't turning the heater on also help cool the engine down quicker?

[Lester]

Originally Posted by m7ammed

Wouldn't turning the heater on also help cool the engine down quicker?

Not if the water pump has failed. No coolant is getting to the heater core. The coolant is stationary in the engine block, first reaching boiling temperature then turning into high pressure steam. At that point, the engine metal is not being cooled, and will eventually reach a temperature that will cause cracking due to thermal expansion, not to mention throwing finely machined moving parts out of tolerance causing undue wear and tear and other damage.

This can happen within a short time, even less than a minute.

Pull the car over and call BMW, AAA or a tow truck.

[kensington]

If they are going to make them fail this early, they need to sell them for $100 and make it easy to replace.