Coolant Temperature

[bimmer525]

I have a 95 525i, and as I was driving home today, it said the coolant was low, and the temparature gauge hit red. I pulled over immediately and let it cool a little and drove home without it hitting red again.

Once home, I saw that the coolant had splattered all over. I filled up the coolant tank to the brim and made sure that I tighten the cap. I tried driving again. I can now go for 1/2 a mile only before the temp shoots to red. I checked to see if the coolant is splattering, it didnot.

Can you guys tell me what to do next?

Thanks in advance.
-Praveen

[E34 530]

First of all, it's not good to just "fill the tank to the brim." When you overfill the tank past its limit, your just taking out the ingrediants and addatives in the coolant that enable it to cool your engine. I had a similar problem with my car in the summer. About 2 times a month, I would go out to my car and there would be a massive pool of coolant on the ground. For some reason, it just drained all of the coolant out in about 3 hours. 2 months later, I figured out it was my waterpump going. Does your engine bay look like this?? This was the result of a broken water pump spewing coolant all over the fan, thus spraying it everywhere around the engine bay.

http://i14.photobucket.com/albums/a314/ripcurl530/2007_0503Image0029.jpg
http://i14.photobucket.com/albums/a314/ripcurl530/2007_0503Image0027.jpg
http://i14.photobucket.com/albums/a314/ripcurl530/2007_0503Image0025.jpg

[dacoyote]

Sounds like a water pump.... when is the last time it was replaced?

[bimmer525]

Sounds like a water pump.... when is the last time it was replaced?
I bought this car two years ago, and it had a new pump then. I doubt its the waterpump, but I could be wrong.

[bimmer525]

Thanks for the pics, and taking the time to answer. No my engine bay did not look like that. The coolant had leaked near the cap, and I thought may be the cap was loose, I didnot realize I should not fill it to the brim. What do you say I do now?

Thanks again,
Praveen

[E34 530]

Thanks for the pics, and taking the time to answer. No my engine bay did not look like that. The coolant had leaked near the cap, and I thought may be the cap was loose, I didnot realize I should not fill it to the brim. What do you say I do now?

Thanks again,
Praveen

I'm not 100% sure, but don't you have to bleed the cooling system on all of the 6 cylinder models? (m20,m30,m50 engines) Maybe that's why your overheating, air in the coolant lines. Don't quote me for this, but it's one of my suggestions because you don't have to bleed the cooling sytem on M60 V8engines.

[bimmer525]

I think you are right, I need to bleed the system and eliminate the possibility of air in the lines. Bleeding the system would remove the air in the lines right?

Thanks

[E34 530]

I think you are right, I need to bleed the system and eliminate the possibility of air in the lines. Bleeding the system would remove the air in the lines right?

Thanks

Right, I think you have to do it multiple times to rid the system of all the air.

[bimmer525]

Thanks for the tip. I will do it first thing tomorrow and get back with the results.

[dacoyote]

I bought this car two years ago, and it had a new pump then. I doubt its the waterpump, but I could be wrong.

Yeah... prop got an airbubble then... 2 years is a little short of a water pump... Did you check the and make sure the plastic part on the rad isn't broken?

[mzarifkar]

I had a similair problem, we have the same car year and engine so this might help.

Fill the radiator with coolant/water, then to the right of your radiator cap is a rather large screw with a phillips head, that is the bleed valve, if it was open, thats where you're leaking coolant, you would hear a hiss coming from it when you overheated. regardless, fill, then run engine, every now and then open the bleed valve, letting out air, you will see your coolant level drop, add more coolant, bleed, repeat.

Keep a screwdriver with you in the car as you may have to bleed again sometime while you're following an ambulance to the hospital in a -20 F windchill....

[bimmer525]

Thanks for the reply..
When you say fill, do you mean to the brim or to the hot/cold level?

[mzarifkar]

first few times, knowing it will drop, i filled up to brim

[bimmer525]

Bled rebled rebled coolant and got all the bubbles out.
It runs as before, but I saw that the radiator cap does not quite fit well. After driving some 25 miles, I saw that some coolant had spurted out. The next time I took the car out, it indicated that the Coolant level was low again.

Got it checked and the diagnosis is that the radiator threads have worn out, and the cap aint sitting well (the cap is a month old).

I have some questions

1. How do I make sure that I am leaking coolant because of a loose cap that does not fit well, or some other reason?
2. Is it worth spending $400 to get a new radiator into it? Or does it really cost that much, and can I get away cheaper?
3. Is there some other way to fix the problem? A good sealant may be?

Thanks again guys,
It runs for now, but want to get the whole thing sorted out soon.

-Praveen

[BMW4LIFE]

i believe there is a recall on the radiator cap...check with bimmer...i know there was one for mine 93 e34...they changed it for free

[Kakaire]

You can replace the expansion tank only and cheaply.